Next Generation Automotive Sun

Visor

Product Development

Nästa Generations Solskydd i Personbil Produktutveckling

Erik Torehov Ronnevik

Faculty of Health, Science and Technology Degree project for master of science in mechanical engineering 30 hp Supervisor: Mikael Grehk Examiner: Jens Bergström 2019-06-17

Abstract

The main purpose of the sun visor is to prevent the driver and passengers to get blinded by the sunlight. It is essential that the sun visor is not blocking the view and that the driver has a clear line of sight so that collisions can be prevented. However, the solution of today is limited as it only covers superior parts of the light and its functionality depends on the head position of the driver and passengers. Therefore, ÅF has initiated this thesis project to develop and improve the product with the goal to further prevent the driver and passengers from being blinded by the sunlight. The scope of the project is to generate new concepts for the sun visor using product development methods.

The product development process involves various phases. Collecting and identifying customer needs and wishes resulted in a detailed requirement specification. Competitor analysis, or benchmarking, was conducted to create awareness of what already exists on the market. New concepts were created by two separate brainstorming sessions. These new concepts were evaluated by concept screening and concept scoring matrices and a final concept was chosen for further development.

The final concept was modeled and developed with all necessary components in CAD with help of the software Catia V5. A material selection was performed on the new components with help of CES Edupack and a final material suggestion for each component was presented.

The new sun visor consists of a sun curtain that is connected to profiles in the WEM cover and the a-pillar. An electric motor in combination with a spring regulates the upward and downward motion of the sun visor to a precise position. The driver or passenger can regulate the height of the sun curtain by pushing a button. An advantage with the new design is that it eliminates the leakage between the sun visor and the WEM cover and to the a-pillar. The designed sun visor does not fit in the current interior of the driver compartment but has been created as close as possible to fit the current space with only small adjustments to the interior. In addition, the components of the new sun visor needs to be redesigned, mainly the WEM cover, to allow the new sun visor to reach down to the lowest allowed point. The new concept has the potential to increase the visibility more efficient than the standard sun visor. Sammanfattning

Solskyddets huvuduppgift är att förhindra att föraren och passagerarna blir bländade av solljus. Det är viktigt att solskyddet inte blockerar sikten samt att föraren har fri sikt så att kollisioner kan förebyggas. Dock är dagens lösning begränsad eftersom den endast täcker en viss del av det inkommande ljuset och dess funktion är beroende av huvudets position. Därför vill ÅF utveckla och förbättra dagens produkt till ett nytt koncept med hjälp av produktutvecklingsmetoder som förhindrar att föraren och passagerarna blir bländade.

Produktutvecklingsprocessen omfattar olika faser. Genom att samla och identifiera kundernas behov och önskemål kunde en detaljerad kravspecifikation erhållas. Konkurrensanalys genomfördes för att skapa medvetenhet om vad som redan finns på marknaden idag. Nya koncept skapades genom brainstormning. Dessa nya koncept utvärderades genom konceptscreening och konceptscoring och ett slutgiltigt koncept valdes för vidareutveckling.

Det slutgiltiga konceptet designades och utvecklades med alla ingående komponenter i CAD med hjälp av programvaran Catia V5. Ett materialval utfördes på de nya komponenterna med hjälp av CES Edupack och ett slutgiltigt materialvalsförslag för varje komponent presenterades.

Det nya solskyddet består av en gardin som är kopplad till profiler i WEM covern och a-stolpen. En elektrisk motor i kombination med en fjäder kontrollerar solskyddets uppåtgående och nedåtgående rörelse till en exakt position. Föraren eller passageraren kan reglera höjden på solskyddet genom att trycka på en knapp. En fördel med det nya solskyddet är att läckage har eliminerats mellan solskyddet och WEM cover samt a-stolpen. Det nya solskyddet får dock inte plats i den nuvarande interiören men har designats så nära som möjligt för att passa i det aktuella utrymmet med endast små ändringar av interiören. Dessutom måste vissa komponenter designas om, huvudsakligen WEM covern, på grund av att gardinen inte går hela vägen ner till den lägsta tillåtna punkten. Det nya konceptet har dock potential att blockera det inkommande ljuset effektivare än det nuvarande solskyddet. Table of contents

1 Introduction 1 1.1 Sun visor ...... 1 1.2 ÅF Industry AB ...... 2 1.3 Objective and purpose ...... 2 1.4 Delimitations ...... 2 1.5 Product Development ...... 3

2 Analysis of current design 4 2.1 Functional content ...... 4 2.2 Components ...... 5 2.2.1 Body ...... 7 2.2.2 Fixing points ...... 7 2.2.3 Hinge ...... 7 2.2.4 Frame ...... 7 2.2.5 Sub frame ...... 7 2.2.6 Vanity pack ...... 7 2.3 Problem identification ...... 7

3 Method 9 3.1 Identification of customer needs ...... 9 3.2 Requirement specification ...... 9 3.2.1 QFD ...... 10 3.3 Competitor analysis ...... 11 3.4 Concept generation ...... 12 3.4.1 Formulation of the problem ...... 12 3.4.2 Functional analysis ...... 12 3.4.3 Creative methods ...... 12 3.5 Concept selection ...... 13 3.5.1 Concept screening ...... 14 3.5.2 Concept scoring ...... 15 3.6 Product design ...... 16 3.7 Material selection ...... 17 3.7.1 Translate design requirements ...... 17 3.7.2 Screen using constraints ...... 18 3.7.3 Rank using objective ...... 18 3.7.4 Seek documentation ...... 18 3.8 Future trends of sun visors ...... 18

4 Results 19 4.1 Identification of customer needs ...... 19 4.2 Requirement specification ...... 19 4.2.1 QFD ...... 20 4.3 Competitor analysis ...... 20 4.3.1 Volvo V60 ...... 20 4.3.2 Tesla Model X ...... 22 4.3.3 Kia Ceed ...... 24 4.3.4 SAAB 9-5 ...... 25 4.4 Concept generation ...... 27 4.5 Concept selection ...... 31 4.5.1 Concept screening ...... 31 4.5.2 Concept scoring ...... 34 4.6 Product design ...... 37 4.6.1 Shaft ...... 40 4.6.2 Housing ...... 41 4.6.3 Curtain ...... 42 4.6.4 A-pillar ...... 42 4.6.5 WEM ...... 43 4.6.6 Roof ...... 44 4.6.7 Snap hook ...... 45 4.6.8 Wheel shaft ...... 45 4.7 Material selection ...... 46 4.7.1 Shaft ...... 46 4.7.2 Housing ...... 50 4.7.3 Curtain ...... 51 4.7.4 A-pillar ...... 51 4.7.5 WEM ...... 52 4.7.6 Roof ...... 52 4.7.7 Snap hook ...... 52 4.7.8 Wheel shaft ...... 52 4.8 Future trends of sun visors ...... 52

5 Discussion 54 5.1 Product development ...... 54 5.2 Product design ...... 55 5.3 Material selection ...... 55 5.4 Future trends of sun visors ...... 55

6 Conclusion 56 6.1 Future work ...... 56

7 Acknowledgments 57

References 58

Appendices 60 1 Introduction

Vehicle functionality is one of the leading segments in innovation and component development. Despite this fact there is a component in the cockpit environment that has kept just about the same function design for various years - the sun visor. The main purpose of the sun visor is to increase visibility on the road by blocking the sunlight. However, the solution of today is limited as it only cover superior parts of the sun and its function is dependent on the head position of the driver and passengers.

The first chapter introduces the concept of a sun visor and the background of the company followed by objective, purpose and delimitations. It also contains an introduction about the subject product development.

1.1 Sun visor The main purpose of the sun visor is to prevent the driver and passengers to get blinded by the sunlight. It is essential that the driver has a clear line of sight so that collisions can be prevented.

The first sun visor that were seen on the market was on a Ford model T in 1924 [1], see Figure 1.1. The sun visor was part of the exterior which is quite different from what are seen today.

Figure 1.1: Ford model T with external sun visor [2].

Today’s sun visor is an interior solution and that was introduced to the market around 1930 [3]. The sun visor has not been modified since then, though some alternative solutions has been designed but never reached the market. The traditional interior sun visor is located in the roof of the car, just above the head of the driver and passenger which is easy to reach when the surrounding light is disturbing. An example of an interior standard sun visor in a car can be seen in Figure 1.2.

1 Figure 1.2: Typical design of a sun visor.

1.2 ÅF Industry AB

ÅF was founded 1845 in Malmö, Sweden and was given the name "The Southern Swedish Steam Generator Association". The main tasks was to perform frequent checks on the safety of steam generators to prevent industrial accidents [4]. ÅF is now a world leading engineering and design company within the fields of energy, industry and infrastructure. They are specialized in areas such as buildings, automotive development and renewable energy. Today, ÅF has 10 000 employees and are based in Europe and their business and clients are found all over the world [5].

The master thesis will be carried out at the research and development department (R&D) at ÅF Industry AB in Trollhättan.

1.3 Objective and purpose The objective of this project is to create new concepts for a sun visor in a car using product development methods.

The report should include following deliverables: • Trends and features in future cockpit referring to the sun visor as system component. • Final proposal(s) of next generation sun visor created in CAD including its hardware such as functions and typical sections. • Results and analysis of the outcome as well as ideas on future actions. The purpose of this project is to design new solutions for the sun visor that has to prevent the driver and passengers from being blinded by the sunlight.

1.4 Delimitations This project will be performed by one student for 20 weeks, 40 hours per week, as a master thesis, 30hp. This report will include the product development of the sun visor which covers analysis of

2 the current design, product specification, concept generation and layout engineering.

The sun visor will be restricted by following aspects:

• The design of the sun visor will be restricted by legal requirements regarding the sun visor, the windshield and the line of sight of the driver.

• No tests will be conducted on the final design of the sun visor.

• The working area of the sun visor will be restricted by the interface of the cockpit, so no adjustment of the surrounding interior will be made.

1.5 Product Development Today, product development is a well established scientific tool when developing new products, but until 1960s, product development was more based on experience and common habit. A turning point regarding product development was when the Japanese industry became a competitor on the world leading market. Japan surpassed its competitors since they worked more systematic with clearly defined development processes and methods. They were highly focused on the products value for the customer with methods satisfying these parameters in the early phases in the development process [6].

The product development process involves synthesis and analysis aspects. Synthesis implicates new technological solutions based on functional requirements. By combining well known scientific technologies, already existing components, experience etc, new technological solutions can be fulfilled. Analysis on the other hand, implicates usage of methods, for example calculations and simulations, to investigate characteristic behaviour of an already existing system [6].

To solve a problem there is a need for a solving process in different steps where synthesis and analysis aspects are connected. These three steps are listed below:

• The process is initiated by identifying and describing the need.

• The process is continued by creating and describing possible alternatives as solutions.

• These solutions are analyzed and evaluated in regard of the needs.

The solution that fulfills all the requirements will be the final alternative. If no solution is found to the problem, the process continuous with a new synthesis of alternatives which are analyzed and evaluated until an acceptable solution is found. This can be described as a synthesis-analysis-loop which requires methods that supports all three phases, requirement specification, synthesis and analysis. By implementing these methods, a higher effectiveness will be reached which enables development of products with high quality in perspective to the customer and a contribution to competitiveness among the developing and producing company [6].

3 2 Analysis of current design

The second chapter gives an overview of the standard sun visor. Functional contents of the sun visor and all of the major components are described. Problems that can occur during use of the sun visor are formulated.

2.1 Functional content The model name and type of the standard sun visor in Figure 2.1, and the name of the manufacturing company that owns the design rights is confidential, and the discussion limited to a functional description.

The standard sun visor is positioned in the roof just above the head of the driver and passenger. The sun visor was disassembled from the car and can be seen in Figure 2.1. The sun visor is included with a illuminated vanity mirror which lights up when the lid is opened. The light from the lamps is useful when there is limited sunlight and the user wants to look themselves in the mirror.

Figure 2.1: The standard sun visor with closed and open lid.

Beside giving protection to the sun light, the sun visor can be seen as a contributing detail to interior class and comfort to the driver and passengers. Using the sun visor is easily done by a one hand operation.

An illustration of the sun visor when its included in the car and the shade that it gives in perspective to forward direction can be seen in Figure 2.2.

4 Figure 2.2: Illustration of the sun visor and the shade it provides.

The following sequences by the sun visor can be accomplished. Through a downward motion the sun visor is folded down, see Figure 2.3.

Figure 2.3: The motion required to fold down the sun visor.

By turning the sun visor left or right, depending on the current situation in the car, the sun visor is regulated to withstand sun light from the side window, see Figure 2.4.

Figure 2.4: The motion that is needed to turn the sun visor towards the side window.

2.2 Components To understand the concept of the standard sun visor in detail, a disassemble in the CAD model was performed. The sun visor consists of following major parts:

1. Body

5 2. Fixing points

3. Hinge

4. Frame

5. Sub frame

6. Vanity pack

All of the components can be seen in Figure 2.5 with its corresponding number from the list above.

Figure 2.5: An exploded view of the different parts in the sun visor.

An overview of the parts that are hidden inside the body and how they are integrated with each other can be seen in Figure 2.6.

Figure 2.6: Integration and connections of parts that are hidden inside the body.

6 2.2.1 Body The body is the part that blocks the incoming light and covers the inner components of the sun visor. The material of the body is a type of thermoplastic, namely polypropylene (PP).

2.2.2 Fixing points The fixing points controls the position of the sun visor. The components that are attached from the roof are linked to the fixing points so it is important that the fixing points are in the right position for optimal function for the sun visor. The fixing points are also made of a thermoplastic.

2.2.3 Hinge By help of the hinge, the sun visor is able to be folded down and be moved up again to the original position. The material of the hinge is unknown.

2.2.4 Frame The frame is the carrying structure of the sun visor and it is integrated with all other components. It is important that the frame is robust enough to carry the body and the other components and also withstand the forces that are applied to the sun visor. The material of the frame is unknown.

2.2.5 Sub frame The sub frame controls the stability of the mirror which needs to be stiff so that the mirror isn’t displaced. The material of the sub frame is also unknown.

2.2.6 Vanity pack The vanity pack consist of a mirror and two lamps which are located to the sides of the mirror, see Figure 2.1. The vanity pack is integrated in the body of the sun visor.

2.3 Problem identification Common practice for forward vision is that the height of the sun visors lower edge when it is folded down vertically (in respect to V1 point) should be about 0-2◦, see Figure 2.7.

Figure 2.7: Height of sun visor with respect to point V1.

7 The point V1 is a set point where the average height and position of the eyes is located. It is determined by measuring the position of the eyes of various test persons which are all of different length and sizes. The sun visor is then regulated by this set point.

The current height and position of the sun visor causes complications for the driver and passengers. A variation in height of the driver and passengers which deviates from point V1 implicates that the sun visor will not fulfill its purpose. The sunlight will not be blocked by the sun visor at all if a person is shorter than point V1.

The sun visor is currently fixed to one position at a time, either to the front windshield or to the side window. It might occur situations when the sun visor is needed in both positions at the same time which the standard sun visor cant satisfy.

The sun visor is currently protecting the driver from the major part of the sunlight. If the sun is setting in a certain angle in perspective to the driver, the light will reach the driver from the outer sides of the sun visor even though the sun visor is folded down.

If the sun sets low, the sun visor won’t protect the driver at all due to the limited height of the sun visor even if the height of the driver is according to point V1.

8 3 Method

The following chapter describes all the methods that was used to develop the new sun visor.

3.1 Identification of customer needs Stakeholders, in context of product development, are all that in some way will be affected or have any comments on the product and its properties during its lifecycle. The stakeholders could be individuals, groups or whole departments inside or outside the company. Requirements and requests from all the stakeholders are collected and considered when establishing the requirement specification [6]. Interviews, field visits to CEVT, China Euro Vehicle Technology AB, and research on the internet was made to identify the requirements and the requests of the stakeholders. The questionnaire that was used during the interviews can bee seen in appendix 1.

3.2 Requirement specification The requirement specification intends to increase additional information which is missing in the description of the project assignment. A specification can be established about what is going to be accomplished, which is made in a way so that the information could be used both as a starting point for the design solutions and as a reference for the evaluation of these solutions and the final product. The requirement specification acquires high amount of information which is developed and updated continuously during the project as more knowledge about the product is gathered [6].

The requirement specification has following purpose [6]:

• To make the problem formulation more concrete

• To ensure that considerations is taken in regard for all the stakeholders, lifecycles and aspects that can affect the product

• To give all involved a clear view of the projects objective

• To make the developing process easier

• To support research of alternative solutions

• To provide a better basis to modify a requirement

The following demands is put on a requirement specification [6]:

• All the stakeholders, lifecycles and aspects must be considered

• The requirements must be formulated as independent of the solution and must be clear

• The requirements should be, if possible, measurable and controllable

• Every requirement must be unique

The requirements can be divided into two main categories. The first category involves requirements which is related to the products expected function, i.e. different functional properties and behaviors that the product is expected to possess or functional effects that the products is expected to deliver. Examples of functional requirements in this category is "carry load", "transmit signals" and "change

9 direction". The other category involves requirements which limits possible solutions for the product. Example of these requirements are "Maximum weight = 400 kg", "Need to fulfill standard XXX " and "Need to follow legal requirement YYY". These types of requirements excludes alternative solutions that doesn’t fulfill the requirements [6].

Requirements can also be divided into demands and wishes. Demands are requirements which always must be completely fulfilled by the final product while wishes are requirements that more or less can be achieved. Therefore, the final product must completely fulfill all the demands to be an alternative product. The wishes on the other hand, can be fulfilled by the product to varying degree. Since wishes is of different importance, weight factors has been assigned to the wishes in a scale of 1-5, where 5 is of highest weight [6].

3.2.1 QFD To connect customer needs with design requirements the Quality function deployment (QFD) method, is applied in the form of the house of quality matrix [6], see Figure 3.1.

Figure 3.1: Example of a traditional QFD-matrix [6].

The background of the term is the interpretation of the concept "quality" which is the QFD methods starting point, namely that a products quality is defined by the costumers experience of the product.

10 The QFD method works as a support for the requirement specification and it is primarily the stakeholder "customer" requirements that is considered. However, the same technique can be used to consider other stakeholders requirements which is combined in the same matrix together with the stakeholder "customers" requirements [6].

The central part in Figure 3.1, is the relationship matrix and is of outmost importance. The stakeholders requirements are identified and compiled to the matrix with their respective weight to the left region of the matrix called "Customer Requirements". These customer needs is expressed as wishes, demands, and answers to what the customer wants. Thereafter, it is important to identify the requirements which can be satisfied and affected by the upcoming design solutions for the product. These design parameters answer to how the customer needs are fulfilled and are compiled to the matrix in the "measurable responses" region [6].

An assessment is based on how strongly the customer needs are connected to the product requirements and the results is inserted to the matrix, following the rating scale:

• 9 = Very strongly connected

• 3 = Moderately connected

• 1 = Weak connection

• 0 = No connection

The matrix values in the "Relationship Matrix", i.e. the connection ratings, is multiplied with the weight factors for the customer requirements and the weighted sum is calculated for every design parameter. This gives extended perception of which design parameters with corresponding demands is most important to meet the needs of the market [6].

It is relevant to identify connection between design parameters, how strongly design parameters interact with each other and if the interdependence is positive or negative. The "roof" of the QFD-matrix consists of diagonals from the various design parameters. The intersection of two different design parameters is marked depending on if the interdependence is positive or negative with following symbols:

• + = Positive relationship

• - = Negative relationship

A positive relationship denotes that improvement in meeting one of the specifications will improve the other, they are synergistic. A negative relationship shows that improvement in meeting one specification may harm the other, a compromise may be forced [7].

3.3 Competitor analysis Competitor analysis is a tool to create awareness of what already exists by examining existing products and reveal opportunities to improve what already exists. Competitor analysis, or benchmarking, is a major aspect of understanding a design problem [7]. The competitor analysis was accomplished by field visits to CEVT, China Euro Vehicle Technology AB, and internet research.

11 3.4 Concept generation In this phase, a synthesis is implemented that results in several conceptual product solutions that fulfills the requirement specifications. The workflow is based on the idea to generate as many product solutions as possible where the final product solution is selected from. By performing this procedure it is ensured that all solutions are identified and none of the best solutions are forgotten [6].

The systematic concept generation is characterized by the functional requirements that concerns the future product, and the creation on many alternative solutions to fulfill these, and a systematic search for solutions is performed by:

1. Formulate the problem in a more broader, abstract and neutral form

2. Implement a functional analysis with division of the product functions in sub functions

3. Search for solutions to the sub functions

4. Combine sub solutions to complete solutions for the entire product

5. Sort out acceptable candidates

3.4.1 Formulation of the problem The purpose of formulating the problem in a broader, abstract and neutral form is to find general solutions to the problem. This implies that a new formulation regarding the concrete and detailed descriptions for the functional requirements in the requirement specification, which results as a basis for the upcoming functional analysis [6].

3.4.2 Functional analysis The purpose of the functional analysis is to create a functional structure which visualizes all the functions which the product and all the included parts need to perform. The result is a functional structure where the products complex total function is realized of the cooperating included sub functions. The purpose of this procedure is to divide the overall problem into several sub problems and find solutions that fulfills every sub function. This is easier than finding a total solution that solves the total complex problem [6].

3.4.3 Creative methods Identification of solutions for the sub functions in the functional structure is made systematically and methodically. It is of utmost importance to generate ideas that can lead to insight, and to successive improve these ideas until there are a practical viable solution to the problem. A creative way to generate ideas and to find solutions is by brainstorming [6].

Brainstorming is performed in a group where the main task is to achieve as many ideas as possible. The amount of ideas is prioritized before the quality of the ideas. The group participants should inspire each other to produce new ideas through associations to other people’s ideas in the group [6].

12 There are four basic rules to take into account when brainstorming:

1. Criticism is not allowed

2. Quantity is sought for

3. Go outside the box

4. Combine ideas

Two different groups were formed for the brainstorming session. One group with employed engineers from ÅF within different working areas. The participants were of different gender, height and age. Seven participants were in this group. The participants from the other group were of other professions with different gender, height and age and a total of six persons were in this group.

The different sub solutions that has been generated to achieve the identified demands for the sub functions is combined to a complete solution for the entire product. The aim is a number of complete solutions which all fulfills the requirements in the requirement specification. A morphological matrix is used for this purpose, see Figure 3.2.

Figure 3.2: An example of how to combine solutions in a morphological matrix [6].

Alternatives that doesn’t satisfy all the requirements or isn’t geometrical or physical compatible or by some other reasons isn’t reasonable is sorted out.

3.5 Concept selection The evaluation of alternative solutions that is generated in the concept generation implies that every alternative should be analyzed with the intention of determining its value and quality relative to the demands and wishes that was formulated in the requirement specification. The task is then to compare the results from the analysis and make a decision about which alternative has highest value and quality [6].

The concept selection process is implemented in following steps:

13 1. Concept screening with an elimination matrix

2. Concept scoring with a weighted relative decision matrix

In the process, the concepts that passes a decision phase are further developed [6], see Figure 3.3.

Figure 3.3: The evaluation of concepts according to Ulrich and Eppinger [6].

3.5.1 Concept screening The first step in the concept selection process is to eliminate less effective concepts. This phase has already begun during the completion of the concept generation phase where a first sorting of unreasonable concepts are performed. The existing concepts are now evaluated in regard to:

• Solving the main problem

• Fulfills all the requirements

• Realizable

• Within the cost range

• Secure and ergonomic

• Suits the company

• Sufficient information

The concepts that entirely fulfills these requirements in addition to the concepts that needs further evaluation proceeds in the process. To support this first evaluation of concepts, an elimination matrix is used, see table 3.1.

14 Table 3.1: Elimination matrix after Pahl and Beitz [6]

The concepts that has been decided to proceed with (+) goes directly to the next evaluation phase. The concepts that needs more information (?) is evaluated in regard to continuation (+) or elimination (-) until a decision can be made [6].

3.5.2 Concept scoring The next step in the concept selection process is evaluation by a weighted relative decision matrix. By using this method, the amounts of concepts is further reduced by sorting out the worst concepts. However, it can occur that new solutions are found through combinations of previous concepts. These new solutions are added to the total amount of concepts [6]. In a weighted relative decision matrix, the selection is based on relative comparisons between different concepts. Following aspects are important to take into account:

• The requirements are based on the requirement specifications wishes and demands.

• Cover all the relevant aspects, but with focus on the problem that the product actually needs to solve.

• A maximum of 15-20 requirements are formulated.

• Merge detailed requirements into groups if necessary.

The selection and evaluation of concepts are then performed with the weighted relative decision matrix, see table 3.2.

15 Table 3.2: Weighted relative decision matrix according to Pugh [6]

The requirements and the concepts are then added into the matrix. A reference concept (DATUM) is also added into the matrix. The reference concept can for example be an already existing concept. All the concepts are now compared to the reference concept. It is now decided, for each of the requirements, whether or not the current concept fulfills the current requirement better than (+), as good as (0) or worse than (-) the reference concept. The result of the comparison (+,0 or -) is added into the current box in the matrix. When all of the requirements and concepts has been processed, every concepts assessment (+,0 or -) are summed up and multiplied with the corresponding weight of the current requirement. The assessments that has been summarized acts as a starting point for the net value that is calculated for every concept which is then ranked based on the obtained net value. Decisions are then made about which concepts to proceed with based on the ranking and the relationship between the net values [6].

Before the next evaluation round, it should also be examined if new, more compatible concepts than the existing can be created through

• Modification of already existing concepts so that their minus evaluation is eliminated. • Combination of concepts with different strengths so that the combined proposal gets considered positive assessments.

3.6 Product design The chosen concept was further developed to a functioning product that fulfilled the requirements in the requirement specification. The objective in this phase was to create a basis that described a functioning and usable product. The design and configuration of the product is made by:

• Dimension and selecting standard components • Design new, unique components • Define the products structure • Describe the products layout

16 The final design was made by CAD with help of the software CATIA V5.

3.7 Material selection The method used to select materials for the sun visor was made with internet research, CES Edupack [8] and with the strategy according to [9], see Figure 3.4.

Figure 3.4: Method to select materials [9].

3.7.1 Translate design requirements In the translation phase, the component is described with functions, constraints, objectives and free variables. The term function is describing what the component is supposed to do, e.g. support a load or contain heat. The term constraints defines which properties that are fixed, e.g. dimensions. An objective is always aimed at when designing a component, e.g. to make it cheaper or to minimize the weight which is the third term in this phase. The final term free variables categorizes which properties that are flexible, e.g. free dimensions or choice of material. These four terms defines the boundary conditions of the choice of material. They are answering to different questions when selecting a material [9]:

• Function - What does the component do?

• Constraints - What nonnegotiable conditions must be met? What negotiable but desirable conditions must be met?

17 • Objective - What is to be maximized or minimized?

• Free variable - Which parameters of the problem is the designer free to change?

3.7.2 Screen using constraints All materials are considered as candidates to begin with. Screening eliminates material candidates that cannot fulfill the constraints set in the translation phase [9].

3.7.3 Rank using objective The materials that are left after the screening are ranked with help of material indices, which measures how well a candidate that has passed the screening can perform. Performance is sometimes limited by a single property or a combination of properties. For example, the best property for buoyancy is a low density and the best property for a heat exchanger is a high thermal conductivity. So by minimizing or maximizing a single property is maximizing performance. The property or properties that are maximizing performance is called material index and following sequence is made for finding a material index [9].

First, the function, constraints, objective and free variables needs to be defined. Secondly, an equation is needed that is describing the quantity to be maximized or minimized, called an objective function, and an equation for the constraints are needed. Thereafter, substituting the equation for the constraints into the objective function gives equation 3.1

P = f (F, G, M) (3.1) Here stands F for functional requirement, G stand for geometric parameters and M stands for material properties which is the material index. The material index is then inserted into CES Edupack to obtain possible material candidates [9].

3.7.4 Seek documentation After the material index is inserted into CES Edupack, a ranked list is obtained with the best material candidates. The next step is to seek documentation about the top listed candidates to found out more about the materials and to pick one that suits the design best. Information about the materials are often found in handbooks, suppliers data sheets, case studies and failure analyses [9].

3.8 Future trends of sun visors Future trends of sun visors was examined by internet research.

18 4 Results

This chapter represents all of the produced results, including identification of costumers needs, requirement specification, competitor analysis, concept generation and selection, product design and material selection.

4.1 Identification of customer needs The identified stakeholders and their input and output towards the project and the sun visor can be seen in table 4.1.

Table 4.1: Identification of customer needs

Stakeholder Input Output ÅF Knowledge and product requirements New product Marketing Customer needs and wishes New product to use Competitors Inspiration Competition on the market Society Legal requirements Safe products Standards Regulations and limitations Safe products

4.2 Requirement specification Following requirement specification was produced. Wishes and demands are marked with "W" and "D" for each requirement.

1. Legal requirements The sun visor must follow regulation ECE 21 paragraph 5.3.4.1 regarding components mounted on the roof, width of projecting parts and downward projection. See annex 10 paragraph 5.3.4.1 for explanatory notes. Alternatively, these projecting parts shall pass the energy-dissipating test according to annex 4 [10]. D The sun visor must follow regulation ECE 21 paragraph 5.4.2.3 regarding metal wires attached to the sun visor and non-rigid attachment elements of the frames of the sun visor [10]. D Regulation ECE No.94 paragraph 1.4.3.7 must be followed regarding the sun visors position [11]. D The sun visor must follow regulation ECE No.94 paragraph 6.2.2 regarding frontal protection airbag and warning labels [11]. D Regulation EEC 77/649 paragraph 2.12 must be followed regarding transparent area of the windshield [12]. D Regulation EEC 77/649 paragraph 5.1.1 - 5.1.1.4 must be fulfilled regarding drivers field of vision and transparent area of the windshield [12]. D Regulation TSFS 2013:63, chapter 31, paragraph 5 must be followed regarding colored films and reflection of the windshield [13]. D Regulation EEC 77/649 paragraph 5.1.3 must be followed regarding obstructions in the drivers 180◦ forward direct field of vision [12]. D

2. Functions The function of the sun visor shall work for the windshield and the side window. D

19 The sun visor should block the incoming sunlight from the windshield and the side window at the same time. W The sun visor shall be able to block the sunlight regardless of the suns position. For instance leakage between the sun visor and the rear mirror. W The sun visor shall be able to block the sunlight regardless of the position of the drivers head. W The sun visor shall be easy to operate so the driving isn’t affected negatively. D The sun visor shall block incoming light regardless of source. W Light from headlights from oncoming cars in the night shall be blocked. W Low time to function. W

3. Design Contain vanity pack W Contain a ticket holder. W The design should implement an interior class and comfort to the driver and passenger. W The design of the sun visor shall not change the design of the surrounding interior. D The sun visor should be user friendly. W Free from noise. D Symmetric design, used for both left and right side of the car. W The sun visor should be robust. W Polarizing effect. W

4. General Low weight. W Few parts. W Recyclable material. W

4.2.1 QFD The final QFD matrix can be seen in Appendix 2. By looking at the weighted ranking, it should be emphasized that blocking incoming light for the windshield and the side window at the same time and block incoming light regardless of source is of highest importance. Following functional requirements should also be prioritized: the sun visor should work for the windshield and the side window, the sun visor should be able to block the sunlight regardless of the suns position and the sun visor shall be able to block the sunlight regardless of the position of the drivers head. It should be highlighted that all of the highest ranked functional requirements concerns blockage of incoming light.

4.3 Competitor analysis Four different competitors was analyzed and following results of the competitor analysis was conducted. Also, a final evaluation of all the competitors can be seen in appendix 3, table A.3.

4.3.1 Volvo V60 One competitor that was analyzed was the sun visor of a Volvo V60, see Figure 4.1.

20 Figure 4.1: The sun visor with closed and open lid.

This sun visor is mounted in the roof and has approximately the same size and shape as the standard sun visor. The sun visor is also able to block incoming light from the windshield and the side window with the same movement pattern as for the current solution. Two details that are different are the ticket holder which Volvo V60 has and just one lamp in the vanity mirror package compared to the standard sun visor.

The sun visor was disassembled and following major components was detected:

An outer layer was detected which covers the body. The material of this component is presumed to be plastic. The outer layer can be seen in Figure 4.2.

Figure 4.2: Outer layer of the sun visor.

The body of the sun visor with and without vanity pack can be seen in Figure 4.3. The material of the body is presumably a thermoset.

21 Figure 4.3: The body of the sun visor with and without the vanity pack attached.

The body was possible to split in half so the content of the body was visible, see Figure 4.4.

Figure 4.4: Half of the body.

Finally, the hinge of the current design was also found in the investigated solution which was attached to the link between the sun visor and the roof, see Figure 4.5. The material of the hinge consists of a metal.

Figure 4.5: The hinge of the sun visor.

The fixing points, the frame and the sub frame of the standard sun visor was observed to be non existing in the sun visor of Volvo V60.

4.3.2 Tesla Model X Another competitor that was analyzed was the Tesla Model X, and they are using a panoramic windshield which differs from the current solution, see Figure 4.6.

22 Figure 4.6: Panoramic windshield of a Tesla Model x. Courtesy: Edmunds.com Inc, [14].

Tesla Model X uses a tinted glass roof to be able to block out sunlight when the sun is positioned above the car. To be able to block out incoming light below the tinted glass without a roof to attach the sun visors to, Tesla uses sun visor that are attached to the A-pillars, see Figure 4.7. The different pillars of the car can be seen in appendix 4, Figure A.4.1.

Figure 4.7: The sun visor attached to the A-pillar. Courtesy: Edmunds.com Inc, [14].

The sun visors are then attached to the rear view mirror via magnets to position the sun visor in front of the driver or the passenger, see Figure 4.8.

23 Figure 4.8: Position of the sun visor. Courtesy: Edmunds.com Inc, [14].

The sun visor also has the ability to be extended to block out even more incoming light which is the condition in Figure 4.8. Incoming light from the side window can be blocked out by lowering the sun visor from the position that can be seen in Figure 4.7. The Tesla Model X also has a vanity mirror inside the sun visor with two lamps (not shown in the figures). No detailed comparison of the components of the sun visors could be completed.

4.3.3 Kia Ceed The third competitor that was analyzed was a Kia Ceed. The sun visor of the Kia Ceed can be seen in Figure 4.9. The sun visor is attached to the roof just above the head of the driver and passenger which is the same case as for the current solution. The sun visor is in a stowed position and it can be visualized that a modification of the roof has been made at the right side of the sun visor so the user has an easier time to pull down the sun visor.

Figure 4.9: The sun visor in a retracted position.

The sun visor in a vertical position can be seen in Figure 4.10. The shape and size of the sun visor

24 is approximately the same as the standard sun visor. A ticket holder is attached to the sun visor and the vanity mirror is opened by a sliding motion of the lid. The lamp is attached to the roof and not beside the mirror with differs from the current solution, see Figure 4.10.

Figure 4.10: The sun visor in a down folded position with visible mirror.

The same movement is used to move the sun visor to the side window as for the current product. The sun visor of the Kia, when located at the side window, is too short to cover the whole length of the side window. Therefore, the driver needs to lean forward in certain situations to prevent from being blinded, see Figure 4.11.

Figure 4.11: The sun visors side position.

4.3.4 SAAB 9-5 The sun visor for a SAAB 9-5 was analyzed due to the special ability to prevent incoming light at the windshield and at the side window at the same time. The sun visors are attached above the head of the driver and passenger and the size of the both sun visors are similar to the current product. The sun visors in a retracted position can be seen in Figure 4.12. A modification to the roof has been made to make the sun visor user friendly. The process to fold down the sun visor is

25 easier.

Figure 4.12: The sun visor in a stowed position.

An option is to have only one sun visor in use at the time, for the windshield or at the side window. The case for the windshield can be seen in Figure 4.13. The retracted position for the second sun visor is located above the first sun visor and the vanity mirror has double lamps for extra illumination, see Figure 4.13.

Figure 4.13: One sun visor in use, preventing incoming light from the windshield with vanity mirror with two lamps.

The combination of having one sun visor facing the side window and free sight at the windshield and the option to have both sun visors in use at the same time can be seen in Figure 4.14.

26 Figure 4.14: Combination of different ways to adjust the sun visor.

The sun visor facing the side window is wide enough to block incoming light from the side, see Figure 4.15.

Figure 4.15: Sufficient blockage from the side.

4.4 Concept generation Elimination of unreasonable concepts has been performed during the concept generation phase and these concepts can be seen in appendix 5. All of the remaining concepts that passed this first elimination phase are presented below.

1 Use a privacy filter for computer screens as a sun visor. Privacy filters blocks the content on the computer screen when looking from the side. The content on the computer screen is only visible when looking directly in front of the computer screen.

2 Use privacy filters for the whole windshield and side windows.

27 3

Tinted glass for the whole windshield and side window. The windshield and side windows are made of a photochromic glass [15], or electrochromic glass [16].

Figure 4.16: Fully tinted windshield and side window.

4

Strips are attached in the windshield and side window that are tinted. The strips are controlled by an eye tracker and the dark spot moves by the position of the head in regard to the incoming light. The strips are made of a photochromic glass or electrochromic glass.

Figure 4.17: Tinted strips in the windshield.

5 The sun visor is fully tinted with photochromic glass or electrochromic glass.

6 The windshield and side windows are made of one way or two way glass which blockades the incoming light.

7 The windshield and side windows are made of opaque glass that can be turned on and off by an electric current. Strips and eye tracker is used as in concept 4.

8 The windshield and side windows are made of colored glass that increases the visibility.

9 The windshield and side windows are polarized which makes the visibility clearer.

10 The sun visor is polarized.

28 11 The car turns into autonomous drive when the incoming light is too strong.

12 Coated window that blocks the light.

13

Use curtains at the windshield and side windows that can be pulled down and up vertically by an electric motor.

Figure 4.18: Vertical curtain.

14

Use curtains at the windshield and side windows that can be extended horizontally by an electric motor.

Figure 4.19: Horizontal curtain.

15

Rotating sun visor which can be angled to the incoming light.

Figure 4.20: Rotating sun visor.

29 16

The sun visor is in a fixed position but extra protection can be unfolded both vertically and horizontally.

Figure 4.21: Extra protection against incoming light.

17

The sun visor is attached to a rail which the sun visor can slide on between the windshield and the side window.

Figure 4.22: Sliding sun visor.

18

Double sun visors that are attached to each other so the sun visor can block incoming light from the front and the side at the same time. The sun visors are also able to be extended vertically.

Figure 4.23: Two sun visor that are attached to each other.

30 19

Ball joints are used so the sun visor is able to be rotated in all directions, both for the windshield and the side window.

Figure 4.24: Sun visor that are maneuvered by the use of ball joints.

20

Two sun visors which are located at the windshield and the side window. The sun visors are able to be extended vertically and horizontally.

Figure 4.25: Two separate sun visors.

4.5 Concept selection The concepts were narrowed down further by implementing concept screening and concept scoring with an elimination matrix and a weighted relative decision matrix.

4.5.1 Concept screening The concepts were added into the elimination matrix and was evaluated and the result can be seen in table 4.2.

31 Table 4.2: Elimination matrix

No concepts directly passed the first screening due to following legal requirements. Regulation EEC 77/649 paragraph 5.1.1 - 5.1.1.4 regarding drivers field of vision and transparent area of the windshield and regulation EEC 77/649 paragraph 5.1.3 regarding obstructions in the drivers 180◦ forward direct field of vision [12]. The geometry of the concepts needs to fit the legal requirements

32 and a second concept screening was made in regard to the geometry that needs to be fulfilled for these legal requirements. The geometry that needs to be fulfilled can be seen in appendix 6. The generated concepts were adapted to fit the legal requirements and the second concept screening can be seen in table 4.3.

Table 4.3: Elimination matrix with concepts adapted to legal requirements

33 Concept 1 that needed more information about the privacy filter was found out during interviews at ÅF. The privacy filter concept has actually been tested as a sun visor with good results during the day but insufficient results during the night. When used at night, oncoming car lights was doubled so four light sources was visualized rather than two.

Concept 5 and 10 could be used as sun visors but must be combined with another sun visor concept. These concepts will be continued with if a decision about a similar solution to the standard sun visor is proceeded with.

Information about coatings for concept 12 were unavailable to find to fit a solution for a sun visor.

4.5.2 Concept scoring The concepts that passed the concept screening phase were inserted into the weighted relative decision matrix and the evaluation can be seen in table 4.4. The reference concept in the weighted relative decision matrix was the analyzed sun visor introduced in chapter 2.

Table 4.4: Evaluated weighted relative decision matrix

All the concepts that was evaluated had a better ranking than the reference concept. The top candidates were concept 13 and 14. Only concept 13 were chosen to be continued with because of the similar solutions and because of the increased visibility if the incoming light is higher up on the windshield. Concept 14 needs to be extended horizontally across the windshield and the sun visor itself blocks the line of sight. A modification of concept 13 was developed to concept 13 b and 13 c, see Figure 4.26, where the curtain is divided into two separate curtains. The curtains in concept

34 13 b is pulled down by an electric motor by pushing a button and 13 c is a mechanical concept where the driver or passenger manually pulls down the curtain.

Figure 4.26: Concept 13 b and 13 c, two separate curtains for the windshield.

A concept of a vertical curtain for the windshield and a horizontal curtain for the side window was also developed called 13 d and 13 e. Concept 13 d is maneuvered by an electric motor and 13 e is maneuvered manually.

Figure 4.27: Concept 13 d and 13 e.

Concept 18 was modified into concept 18 b, see Figure 4.28, where the sun visors are able to be extended horizontally.

Figure 4.28: Concept 18 b.

No modifications was found for concept 3, 4, 7 and 20 but they were all passed on to the fourth selection.

Concept 13 had the highest net value in the first selection which made the modified concept 13 b a good candidate as a reference concept in the fourth selection, see table 4.5.

35 Table 4.5: The second weighted relative decision matrix

Concept 13 b and 13 d were the superior candidates. However, 13 d was easier to implement in the front door due to more space in the side frame of the door. Concept 13 b had a limited space and a decision was made to move forward with concept 13 d for further development. In comparison to the standard sun visor, the curtain solution covers more of the windshield and side window which provides better blockage for incoming light. Also, the leakage between the sun visor and the rear mirror is eliminated. If the light is located from the passenger side, there is an option for the driver to extend the sun visor horizontally which is not available in the current solution.

Furthermore, the design of the new sun visor was adapted to a car with a WEM cover as a feature. The chosen concept was modified to fit the WEM covers design but the concept itself was the same. The WEM cover was not taken into account during the concept generation phase due to a risk of limited concepts. A typical WEM cover can be seen in Figure 4.29.

36 Figure 4.29: WEM cover with rear view mirror attached.

4.6 Product design The new sun visor in a front view can be seen in Figure 4.30, and rear view in Figure 4.31, where the sun curtain is folded out along the windshield. The new sun visor does not fit in the current car due to limited space but is designed as closely as possible to the available space. The sun visor for the side window was not designed in CAD due to limited time and is left for future work.

Figure 4.30: Final design of the sun visor for the windshield.

37 Figure 4.31: Rear view of the sun visor.

The curtain is attached to a shaft which it is rolled up by a motor, see Figure 4.32. The shaft is stabilized with housings which are screwed to the inner roof. Plain bearings are assembled between the shaft and the housing to make an easier rotating motion for the curtain when it is rolled up and down. Circlips are stabilizing the shaft so no axial movement is available. A motor is attached to the shaft but the exact size and type of motor is not decided and is left for future work.

Figure 4.32: The left shaft that the curtain is attached on and the rear mirror can be seen.

The curtain is rolled down through a gap in the roof and is guided in the right direction by snap hooks, see Figure 4.33.

38 Figure 4.33: Side view of the sun visor.

The lower part of the curtain is attached to a shaft with wheels and the wheels are rolling in a profile located in the a-pillars and the WEM cover, see Figure 4.34.

Figure 4.34: Profiles in the WEM cover where the wheels are located.

Extension springs are attached to the a-pillar, WEM cover and to the wheel shaft, see Figure 4.35-4.36. The extension springs are pulling the curtain down due to the tension in the springs and the motor are controlling the upward motion. By stopping the motor, the curtain is set to a specific height.

39 Figure 4.35: Spring attached to the wheel shaft for the A-pillar.

Figure 4.36: Spring attached to the wheel shaft for the WEM cover.

The length of the springs needs to be exactly as long as the height of the curtain that goes down to point V1 to be able to cover the incoming light. The springs can be extracted to the inner roof but they can’t be compressed to the bottom of the A-pillar or to the WEM cover. The springs has a bottom position and they can’t be compressed below that point. The profile in the A-pillar can be elongated so the spring can reach the length of point V1 and to the inner roof but the WEM cover can’t be elongated below point V1. This problem leads to that the curtain can’t go down fully to point V1 and all the incoming light won’t be blocked.

4.6.1 Shaft The shaft is the component where the curtain is rolled up to by a motor and can be seen in Figure 4.37.

40 Figure 4.37: Shaft for the sun curtain.

The shaft has a profile where the end of the curtain is attached in with the same width as the sun curtain. Two profiles is located near the end of the shaft where circlips is assembled against the plain bearings which makes the shaft more stabilized. One end of the shaft has an opening for the shaft from the motor which fits between the motor shaft and the curtain shaft.

4.6.2 Housing The housing of the shaft can be seen in Figure 4.38. The inner diameter is bigger than the shaft due to make space for a plain bearing that is attached between the shaft and the housing for easier sliding. The housing is screwed to the inner roof of the car.

41 Figure 4.38: Housing for the curtain shaft.

4.6.3 Curtain The curtain has the width according to the length between the a-pillar and the WEM cover to be able to block incoming light to the car as much as possible. The length of the curtain is limited to point V1 and to the shaft that connects with the curtain. The curtain has a bit of transparency which makes it possible for the driver to see contours in the drivers field of vision but still blocks the incoming light.

4.6.4 A-pillar A simplified a-pillar was made in CAD, see Figure 4.39. A profile can be seen where the curtain is rolling up and down. The length of the profiles enables the sun curtain to go down to point V1.

42 Figure 4.39: The outside and inside of the a-pillar.

Ribs are attached to the profiles to make them more stable, see Figure 4.40.

Figure 4.40: Profile with ribs.

4.6.5 WEM A simplified WEM cover was made in CAD with exact same profiles and ribs as for the A-pillar, see Figure 4.41. The WEM cover is larger than its precursor due to that the sun curtain is going

43 down to the V1 point so the WEM cover needs to be elongated. There are no legal requirements that says that the WEM cover can’t go down to that point.

Figure 4.41: Simplified WEM cover with profiles and ribs.

4.6.6 Roof The inner roof of the car can be seen in Figure 4.42 where gaps for the curtain to pass through can be seen and screw holes for the housing.

44 Figure 4.42: Inner roof of the car.

4.6.7 Snap hook The snap hooks stabilizes the component so the rail can guide the curtain to the right path, see Figure 4.43. The snap hook is resilient which makes it easy to assemble into the roof. The snap hooks has been designed in regard to the guidelines that ÅF uses, see appendix 7.

Figure 4.43: Snap hooks and rail for the sun curtain.

4.6.8 Wheel shaft The shaft for the wheels and lower part for the curtain which stabilizes the curtain can be seen in Figure 4.44. The curtain encircles the middle part of the shaft and the ends of the shaft is attached to the wheels that rolls in the profiles of the a-pillars and the WEM cover.

45 Figure 4.44: Shaft for the wheels and sun curtain.

4.7 Material selection In this chapter, a material selection is presented for all the new components.

4.7.1 Shaft Following function, constraints, objectives and free variables was determined for the shaft.

• Function - Carry load

• Constraints - σy ≥ σmax, recyclable • Objective - Minimize cost and weight

• Free variable - Radius, r, material

The forces acting on the shaft was approximated as in Figure 4.45. The shaft is represented as a beam with an uniformly distributed load acting on it. The uniformly distributed load occurs due to the weight of the wheel shaft that is holding the curtain in place when in use and the weight of the curtain, see equation 4.1.

Q = (mcurtain + mwheelshaft) g = 3.2N (4.1)

46 Figure 4.45: The load case for the shaft.

Following properties are used when obtaining the maximum stress in the shaft: r = 0.007m, Q = 3.2N, L = 0.541m

The maximum stress in the shaft was calculated in following equations to be used as a restriction in the material selection process. The maximal moment for the beam can be seen in equation 4.2, [17].

QL2 M = (4.2) max 8 The expression for the moment of inertia can be seen in equation 4.3, [17].

πd4 I = (4.3) 64 The expression for bending resistance can be seen in equation 4.4, [17].

I d W = , e = (4.4) e 2 Finally, by inserting equation 4.2 - 4.4 into equation 4.5, the maximum stress in the beam could be calculated.

M 4QL2 σ = max = ≈ 0.43MP a (4.5) max W πd3 The expression for the yield strength of the beam can be seen in equation 4.6.

M 4QL2 QL2 σ = σ = max = = (4.6) y max W πd3 2πr3 An expression for the free variable, the radius, could be found by reformulating equation 4.6, see equation 4.7.

!1/3 QL2 r = (4.7) 2πσy The mass equation for the shaft combined with equation 4.7 gives a final expression for the first material index M1, see equation 4.8

!2/3 ! QL2  Q 2/3   ρ m = ρAL = ρπr2L = ρπL = π L7/3 (4.8) 2/3 2πσy 2π σy | {z } | {z } | {z } F G M

47 By inverting and maximizing M1, a first screening could be made with equation 4.9 and CES Edupack, see Figure 4.46. The constraints for the yield strength and that the material should be recyclable was also inserted as constraints in CES Edupack. The best materials for the shaft is the materials above the line which has a slope of 1.5. The material groups that could be used was foams, metals and alloys and composites.

σ2/3 M = y (4.9) 1 ρ

Figure 4.46: The best materials according to M1 [8].

By inserting equation 4.7 into the an equation regarding the cost, a second material index could be found, see equation 4.10

!2/3 ! QL2  Q 2/3   ρC 2 7/3 m C = ρALCm = ρπr LCm = ρπLCm = π L (4.10) 2/3 2πσy 2π σy | {z } | {z } | {z } F G M

Inverting and maximizing the second material index M2, see equation 4.11, a second screening could be made with CES Edupack, see Figure 4.47. The constraints for the yield strength and that the materials should be recyclable was also inserted into CES Edupack. The best materials are above the line with a slope of 1.5. The material groups that fits the second material index was non-technical ceramics, metals and alloys, fibers and particulates and natural fibers.

ρCm M2 = (4.11) 2/3 σy

48 Figure 4.47: The best materials according to M2 [8].

To be able to rank the best materials, a trade off curve was made regarding both M1 and M2, see Figure 4.48. The best materials are located nearest the trade off line.

49 Figure 4.48: The best materials with respect to weight and price [8].

The properties of the best ranked materials [8], see table 4.6.

Table 4.6: Properties of the best ranked materials.

ADI 1600 AISI 440C AISI 9255 AISI 5160 AISI M47 Density (kg/m3) 7000-7100 7700 - 7900 7800 - 7900 7800 - 7900 7880 - 8040 Price (SEK/m3) 18000 - 19100 67700 - 80400 43200 - 47000 42600 - 46300 462000 - 515000 Yield strength (MP a) 1260 - 1470 1710 - 2090 1840 - 2260 1610 - 1980 2370 - 2810 Recyclable Yes Yes Yes Yes Yes

All the best materials has almost equal properties but they have different processing properties. ADI 1600, AISI 440C and AISI M47 has poor processing properties which are of importance of the shaft because of its small dimensions. AISI 9255 and AISI 5160 has excellent processing properties which is preferable in this case. The final choice for the material for the shaft is decided to be AISI 9255 or AISI 5160.

4.7.2 Housing The housing component is approximately exposed to the exact same load as for the shaft. According to the yield strength in table 4.6, the yield strength is way much higher than its needs to be which makes the material selection to be the same as for the shaft. AISI 9255 or AISI 5160 was chosen to be the best material selection for the housing.

50 4.7.3 Curtain The material selection for the curtain was completed by internet research due to limited functions in CES Edupack. A curtain made of cotton shrinks when exposed to heat and moisture which excludes cotton or any fabric as a material for the curtain. The scenario that occurs when the incoming sun light hits the sun curtain can be seen in Figure 4.49. A curtain that blocks out enough light so the driver or passenger won’t be blinded and still be able to see contours through the curtain has a maximum of 5% transmission and 45% absorption. A curtain with these properties is made of 100% polyester plus a thin layer of acrylic to withstand dirt [18].

The weight of the curtain was calculated with equation 4.12 to be able to calculate the uniformly distributed load on the shaft.

m = ρV = 1400kg/m3 ∗ 1.79 ∗ 10−4m3 ≈ 0.251kg (4.12)

Figure 4.49: Illustration of the phenomenon that occurs when the incoming sun light hits the curtain [18].

4.7.4 A-pillar No new material selection was made for the a-pillars, the same material is used for the a-pillars as before.

51 4.7.5 WEM No new material selection was made for the WEM cover, the same material is used for the WEM cover as before.

4.7.6 Roof No new material selection was made for the roof, the same material is used for the roof as before.

4.7.7 Snap hook The material selection for the snap hook was chosen to be the same as for the snap hooks in the a-pillar which works as a ventilator.

4.7.8 Wheel shaft The wheel shaft needs to pass the energy-dissipating test according to regulation ECE 21 paragraph 5.3.4.1, due to the risk of head impact of the driver and passenger. Therefore, the material selection for the wheel shaft was chosen to be the same material as the body of the standard sun visor which was known to pass the energy-dissipating test and the body was made of polypropylene. The density of polypropylene is approxemately, ρ ≈ 900kg/m3 [19]. The volume of the wheel shaft is 8.5 ∗ 10−5m3. The mass could therefore be calculated with equation 4.13 and the mass was taken into account when calculating the uniformly distributed load for the shaft.

m = ρV ≈ 0.076kg (4.13)

4.8 Future trends of sun visors The upcoming trends in the automotive sun visor industry offers a limited amount of concepts that follows legal requirements or increased visibility of the driver. Volkswagens invention of an electronic sun visor embedded in the glass that produces a dark spot that moves accordingly to the drivers or passengers position of the eyes and the position of the incoming light with help of sensors is one of the most exiting trends [20]. The technology is available for a sun visor that blocks more incoming light than the standard sun visor. However, this concept is limited by the legal requirement of at least 70% light transmission for the windshield [12].

Another concept of a sun visor that Continental has presented is the Intelligent Glass Control which uses special films that changes the transparency through electric control signals. The window darkens with a push of a button, so the driver can manually dim the window [21], see Figure 4.50. However, the standard sun visor blocks more incoming light than the concept from Continental due to that the standard sun visor can go down to point V1, see appendix 6.

52 Figure 4.50: Windshield with changeable transparency [21].

Furthermore, with the upcoming driverless cars, the interior could look completely different, see Figure 4.51, and the sun visors could probably be completely different. The whole car could be dimmed out to a pleasant incoming light when the autonomous driving is in use for instance.

Figure 4.51: Interior of Mercedes-Benz F 015 [22].

53 5 Discussion

In following chapter a discussion is made about the product development method, the results of the product design and the material selection.

5.1 Product development Overall, the product development process has been helpful and has provided a good structural method during the project. The product development method has provided clear working tasks of what to do, to achieve best results in the different phases of the project. It was revealed during the concept selection phase how useful it was to have this structural way of developing a product. Some concepts that were created during the brainstorming session were in the beginning favored as a new sun visor but it was realized in the concept screening and concept scoring phase that these concepts were not applicable as a new sun visor at all [6]. Thanks to having a methodical approach, the best final concept for the sun visor could be selected.

The questionnaire was a good way to handle the identification of customer needs, see appendix 1. Same questions for different persons eased the process of gathering customer needs and wishes to the requirement specification.

The legal requirements in the requirement specification was hard to gather and to understand. One big problem was to understand what potential legal requirements could affect a new concept for a sun visor. Contacting CEVT for expertise was a big advantage in this matter.

To have access to a physical product in the competitor analysis was beneficial. Components and their interaction and materials could be analyzed even further, even though the final concept of the sun visor was completely different. A big part of the competitor analysis was to look at pictures of sun visors of different car brands, a physical sun visor of each car brand would have been preferable even though inspiration for new concepts was found during this process.

The concepts that was generated through the brainstorming session with two different groups of people was not that much of a difference. The sun visor is applicable for every person that has ever been in a car which gives a feeling about what the problem is and what changes that might be possible. This might be the reason that the concepts was so similar between the two groups.

The concept selection phase provided a good method of narrowing down concepts with concept screening and scoring [6]. However, the final concept provided a good way of dealing with incoming light but it wasn’t clear how it should be implemented in the car. A second brainstorming sessions should maybe have been done in this phase of the project with focus on technical solutions of how the sun curtain should be implemented in the car. Another way that might have helped with a more detailed concept of the sun visor is to have more iteration of the concept and try to find more modified solutions to the problem.

54 5.2 Product design The new sun visor doesn’t fit in the current interior and the limited space did not appear as a problem when the concept screening and concept scoring was made. The limited space was a big problem when designing the new sun visor and a lot of time was spent on this problem. A technical brainstorming session might have helped to find possible solutions to the limited space. Also, the solution of having an extension spring connected to the wheel shaft entails that the sun curtain can’t go down to point V1. To have an extension spring connected to the sun curtain or a similar solution that keeps the sun curtain in tension all the time is believed to be the best solution to keep the sun curtain in place together with the motor. Further development of the extension spring and the connection to the sun curtain needs to be done. However, the concept for the sun visor covers more incoming light than the previous sun visor. Leakage has been removed between the rear mirror and the sun visor and also between the a-pillar and the sun visor.

The sun visor for the side window was not designed in CAD due to limited time. The sun visor would probably have the same difficulties to be implemented in the car as the sun visor for the windscreen. Both in terms of limited space and how the sun curtain should be able to go up and down.

5.3 Material selection The material choice for the new components was either produced with CES Edupack or by choosing the same material as the previous component. The shaft that is connected to the motor was approximated as a beam with an uniformly load acting on it and the maximum stress in the shaft could be calculated. The maximum stress in the beam could be investigated with FEM analysis to see if the calculated maximum stress is a misleading results, even if the external forces on the sun visor is low. If that is the case, then the material selection in CES Edupack might be different because of the inserted restriction of the yield strength.

The method of interviewing persons with expertise in sun curtains was a good way of getting knowledge for the material choice of the curtain.

5.4 Future trends of sun visors The similarity between the found future concepts was a lot similar to the concepts that was found during the brainstorming sessions. The concept from Volkswagen [20] and the concept from Continental [21] corresponds in fact to concept 4 and concept 3 to some extent in the concept generation section. These concepts are only valid in a certain area of the windshield, see Figure A.6.1 in appendix 6, and the standard sun visor is able to go further down on the windshield, point V1, which results in that it covers more incoming light. However, the future concepts eliminates the leakage between rear mirror and sun visor and a-pillar and sun visor completely which the standard sun visor does not.

55 6 Conclusion

A total independent sun visor regarding the position of the drivers head could not be found due to legal requirements.

The new concept for the sun visor consists of a sun curtain that is able to block the incoming light to a greater degree than the previous sun visor and is considered to be a better alternative regarding the position of the drivers head. Leakage between the rear mirror and the sun visor is removed and also between the a-pillar and the sun visor. The sun visor can be used at the same time for the windshield and the side window and follows all the legal requirements that affects the new concept. Also, if the incoming light is located from the passenger side, the passengers sun visor is able to be activated by the driver by pushing a button.

The designed sun visor does not fit in the current interior of the car but has been created as closely as possible to fit the current space. Also, the components of the new sun visor needs to be redesigned due to that the new sun visor doesn’t go all the way down to point V1. This means that the designed sun visor doesn’t block as much incoming light as the previous sun visor. This needs to be solved to be able to implement the conceptual model.

6.1 Future work Following parameters was left for future work due to limited time.

Cost calculations needs to be done to present expenses and the difference in price compared to the previous sun visor.

The sun visor for the side window needs to be designed. Focus on how to implement the sun visor in the current space and how to control the upward and downward motion of the curtain should be made.

The exact type of motor and extension springs needs to be analyzed due to have the right balance between the tension in the spring and the power of the motor.

The material that was chosen for the curtain needs to be tested to see if contours can be distinguished and if the material is able to block out all the incoming light in the sun curtains area.

56 7 Acknowledgments

I would like to thank my supervisors Thomas Bratt and Isabel Hwang at ÅF and Mikael Grehk at Karlstad University for their fully support during this project. Also, a special thanks to CEVT for their help and guidance regarding any questions related to sun visors.

Erik Torehov Ronnevik

Trollhättan - June 2019

57 References

[1] Tom. Collins. The legendary Model T Ford : the ultimate history of America’s first great automobile. Krause Publications, 2007, p. 303. isbn: 0896895602. [2] May | 2015 | OLDMOTORSGUY.COM. url: https : / / oldmotorsguy . com / 2015 / 05/ (visited on 30/01/2019). [3] Michael L. Berger. The automobile in American history and culture : a reference guide. Greenwood Press, 2001, p. 487. isbn: 0313245584. [4] ÅF. History - About ÅF - ÅF. 2018. url: http://www.afconsult.com/en/about- af/ history/ (visited on 24/01/2019). [5] ÅF at a glance. url: http://www.afconsult.com/en/about-af/at-a-glance/ (visited on 28/01/2019). [6] Hans Johannesson, Jan-Gunnar Persson and Dennis Pettersson. Produktutveckling Effektiva metoder för konstruktion och design. 2:nd. Poland: Liber AB, 2013, p. 720. [7] The Mechanical Design Process. Tech. rep. 2008. url: http://160592857366.free.fr/joe/ ebooks/Mechanical%20Engineering%20Books%20Collection/MACHINE%20DESIGN/The% 20Mechanical%20Design%20Process.pdf. [8] CES EduPack | Granta Design. url: https : / / grantadesign . com / education / ces - edupack/ (visited on 23/04/2019). [9] Michael F Ashby. Material Selection in Mechanical Design. 4:th. Butterworth-Heinemann, 2011. isbn: 9781856176637. [10] EUR-Lex - 42008X0716(01) - EN - EUR-Lex. url: https://eur-lex.europa.eu/legal- content/GA/TXT/?uri=CELEX:42008X0716(01) (visited on 20/02/2019). [11] Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles, Equipment and Parts which can be Fitted and/or be Used on Wheeled Vehicles and the Conditions for Reciprocal Recognition of Approvals Granted on the Basis of these. Tech. rep. 1995. url: https://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/2017/ R094r3e.pdf. [12] No L. Official Journal of the European Communities. Tech. rep. url: https://eur-lex. europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:31977L0649%7B%5C&%7Dfrom=en. [13] TSFS 2013:63 VÄGTRAFIK. Tech. rep. url: https : / / www . transportstyrelsen . se / tsfs/TSFS%202013%7B%5C_%7D63.pdf. [14] Panoramic Windshield - 2016 Tesla Model X Long-Term Road Test. url: https://www. edmunds.com/tesla/model- x/2016/long- term- road- test/2016- tesla- model- x- panoramic-windshield.html (visited on 21/02/2019). [15] A. V. (Alexander Victorovich) Dotsenko, L. B. (Leonid Borisovich) Glebov and Viktor Alekseevich. TSekhomskii. Physics and chemistry of photochromic glasses. CRC Press, 1998, p. 190. isbn: 0849337801. [16] A Bright Future - How Smart Windows Work | HowStuffWorks. url: https : / / home . howstuffworks . com / home - improvement / construction / green / smart - window4 . htm (visited on 22/03/2019). [17] Karl Björk. Formler och tabeller för mekanisk konstruktion. 7:th. Spånga: Karl Björks Förlag HB, 2013, p. 72. isbn: 9192631770.

58 [18] Rullgardiner - Rollodin. url: https://www.rollodin.se/ (visited on 23/04/2019). [19] Density of Plastics Material: Technical Properties Table. url: https://omnexus.specialchem. com/polymer-properties/properties/density (visited on 24/04/2019). [20] Volkswagen’s Electronic Sun Visor - CardinaleWay Volkswagen. url: https://www.cardinalewayvw. com/blog//volkswagens-electronic-sun-visor/ (visited on 06/05/2019). [21] Continental Automotive - Intelligent Glass Control. url: https : / / www . continental - automotive.com/en-gl/Passenger-Cars/Interior/Comfort-Security/Intelligent- Glass-Control?fbclid=IwAR3qV7dp1c%7B%5C_%7DARMrPLkY0zAZ1sVu9n1%7B%5C_%7Dvvf2P9y8VXatIshpCcPtdJxX1PKo (visited on 06/05/2019). [22] Self-Driving Cars Will Require a Whole New Marketing Language | MediaVillage. url: https: //www.mediavillage.com/article/self-driving-cars-will-require-a-whole-new- marketing-language/ (visited on 06/05/2019).

59 Appendices

Appendix 1. Questionnaire

1. What functions are positive about the sun visor?

2. What functions are negative about the sun visor?

3. What is positive about the sun visors appearance?

4. What is negative about the sun visors appearance?

5. Do you want to change anything with the sun visor? Design or function?

6. How can the sun visor be improved?

7. Does the sun visor fulfill its purpose?

8. Under what circumstances are the sun visor sufficient?

9. Under what circumstances are the sun visor insufficient?

10. Is the current solution user friendly? What can be different?

11. Is the sun visor positioned properly?

60 Appendix 2. QFD

+ + + + + + + + + + + + + + + + + + + + + + + + + +

Column # 1 2 3 4 5 6 7 8 9 10 11 12 Functional Requirements

Customer Requirements Row # Customer Importance Work for windscreen and side window Block incoming light for windscreen and side window Independent of the suns position Independent of the position of the drivers head Easy to operate Block incoming light at night Block incoming light regardless of source User friendly Free from noise Symmetric design Low time to function Polarizing effect 1 3 3 3 3 3 5.3.4.1 paragraph 21 ECE regulation Follow 5 1 2 5 Follow regulation ECE 21 paragraph 5.4.2.3 1 1 1.4.3.7 paragraph No.94 ECE regulation Follow 5 3 3 6.2.2 paragraph No.94 ECE regulation Follow 5 4 5 5 Follow regulation EEC 77/649 paragraph 2.12 9 9 9 9 3 9 9 3 1 3 3 9 6 5 Follow regulation TSFS 2013:63, chapter 31, paragraph 5 9 9 9 9 3 9 1 3 3 3 3 6 5 Follow regulation EEC 77/649 paragraph 5.1.1 - 5.1.1.4 9 9 9 9 3 9 3 9 8 5 Follow regulation EEC 77/649 paragraph 5.1.3 9 9 9 9 3 3 9 3 3 1 1 9 2 Vanity pack 3 3 3 3 1 10 4 Interior class and comfort 3 1 3 3 1 3 11 2 Ticket holder 1 1 1 3 12 2 Not implicate adjustments of interior 3 3 1 1 1 1 3 1 1 3 1 1 13 3 Low weight 3 3 1 1 1 14 3 Few parts 1 1 1 1 3 1 1 3 3 3 1 1 15 2 Robust 3 3 3 1 1 16 3 Recyclable material 1 1 Weighted ranking 194 204 200 200 76 110 204 73 63 101 51 153

Figure A.2: The final QFD matrix.

i

1 This legal requirement has to be followed, but in this case, there are no functional requirement that depends on that regulation.

61 Appendix 3. Competitor analysis

Table A.3: Compiled analysis of the competitors

Volvo V60 Tesla Model X Kia Ceed Saab 9-5 Position Roof A-pillar Roof Roof Extra sun No No No Yes protection Adjustable size No Yes No No Type of vanity Lid Lid Slider Lid opener Mirror Yes Yes Yes Yes Number of 1 2 1 2 lamps Position of the Sun visor Sun visor Roof Sun visor lamps Ticket holder Yes No Yes No Less components New attachment Protection from was used for this solution. Insufficient light incoming light at Remarks product than for Attached to the protection at the the windshield the current A-pillar instead side window. and side window solution. of the roof. at same time.

62 Appendix 4. Car pillars

Figure A.4.1: Visualization of the different pillars of the car. Courtesy: Edmunds.com Inc, [14].

63 Appendix 5. Generated concepts

21 Manually deploy some sort of fog in front of car that covers the car from incoming light.

22 The HUD, Head Up Display, blocks incoming light by interfering with the light.

23 There are no windows, the driver uses VR glasses instead with real time data that filters the light away.

24 TV screens are used as windshields and side windows that shows the surrounding environment with pleasant light.

25 Change the interiors light based on outside light which makes increases the visibility.

26 Sun panels that are attached outside the roof that works as sun cover. The sun panels can be extended depending on the incoming lights position.

Figure A.5.1: Sun panels on the roof of the car.

27 An umbrella is folded out inside the car which covers the incoming light in all directions.

Figure A.5.2: Umbrella inside the car.

64 28 A movable sun visor is attached to the windshield and the side window at all time. The sun visor is freely movable around the interior so that the incoming light is blocked at any position.

Figure A.5.3: Movable sun visor.

65 Appendix 6. Geometry of legal requirements

Regulation EEC 77/649 paragraph 5.1.1 - 5.1.1.4 refers to the drivers field of vision and the transparent area of the windscreen. The transparent area of the windshield must include following datum points [12]:

◦ • A horizontal datum point forward of V1 and 17 to the left, see Figure A.6.1.

◦ • An upper vertical datum point forward of V1 and 7 above the horizontal.

◦ • A lower vertical datum point forward of V2 and 5 below the horizontal. • To verify compliance with the forward vision requirement on the opposite half of the windshield, three additional datum points, symmetric to the earlier defined datum points in relation to the median longitudinal plane of the vehicle, are obtained.

Figure A.6.1: The geometry of the transparent area of the windshield [12].

Regulation EEC 77/649 paragraph 5.1.3 refers to obstructions in the drivers 180◦ forward direct field of vision. There shall be no obstructions in the drivers 180◦ forward direct field of vision below a horizontal plane through V1 and above three planes through V2, one being perpendicular to the plane X-Z and declining forward 4◦ below the horizontal and the other two being perpendicular to the plane Y-Z and declining 4◦ below the horizontal, see Figures A.6.2 - A.6.3. Exceptions in the drivers 180◦ forward direct field of vision are A pillars, vent window division bars, rear-view mirrors and windscreen wipers [12].

66 Figure A.6.2: The field of obstruction seen from the side [12].

Figure A.6.3: The field of obstruction below the horizontal plane [12].

67 Appendix 7. Design of snap hooks

In principle, long snap hooks should be aimed at. See Figure A.7.1 for definition of dimensions.

• The larger the hook length l, the lower the marginal fiber expansion, which can lead to breakage

◦ ◦ ◦ • Joining angle α1 should usually be 15 -30 , maximum 60

◦ • Release angle α2 influences the transferable forces of the snap hook; at 90 self-locking (permanent connection)

• Undercut to design f depending on the size of the forces to be transmitted

Figure A.7.1: General modeling of snap hooks.

68