PROJECT TITLE:
DESIGN AND MANUFACTURING OF A WHEELCHAIR-TRICYLE ATTACHMENT Rodrick H. Shangali B Sc. Mechanical. Eng
SHANGALI RODRICK
OVERVIEW OF PRESENTATION
• Introduction
• Background of the project
• Problem statement • Project objectives • Literature review • Methodology • Analysis • Design • Manufacturing and Testing • Results
SHANGALI RODRICK
INTRODUCTION
• A hand tricycle works in the same way as a bicycle as it uses a chain system with pedals to drive the wheels.
• Except, in the case of a hand tricycle, the chain is attached to hand pedals, allowing the user much more efficient propulsion than would be provided from the push rims on a wheelchair.
SHANGALI RODRICK
BACKGROUND OF THE PROJECT
In most developing countries, people with disabilities do not have the opportunity of adapted roads, ramps, or handicapped accessible transportation.
As a result, wheelchair users often rely solely on their own power for both long and short distance travel.
SHANGALI RODRICK CONTD…
Mobility aids currently used do not fully suit user needs; wheelchairs are exhausting to push on rough ground, while hand-powered tricycles, which are more efficient to propel, but they are too large to use in the house.
SHANGALI RODRICK
PROBLEM STATEMENT
The requirements of the two different environments exert mutually exclusive functional demands on the wheelchair systems.
Crucial points being described are such as unable to use for both indoor/ outdoor activities
Some of the designs are complex and expensive
Performance is low for manual wheelchair
They require large usage of human energy (increase tiredness) and coverage of distance.
SHANGALI RODRICK PROJECT OBJECTIVE
MAIN OBJECTIVE
The main objective was to design and manufacture a cost effective wheelchair tricycle attachment for easier accessibility and increased performance to the wheelchair user.
SHANGALI RODRICK CONTD…
SPECIFIC OBJECTIVES
The specific objective was to:
• Investigate the existing driving systems for both wheelchairs and tricycles.
• Design and manufacture a wheelchair tricycle attachment for better accessibility and performance of a wheelchair user.
• Test and evaluate the developed wheelchair tricycle attachment.
SHANGALI RODRICK LITERATURE REVIEW Each wheelchair user has his/her unique set of needs.
A wheelchair is required to take into account the following wheelchair users requirements:
• Home environment as at rural, urban, crowded and flat areas.
• Disability, i.e. Amputee, Polio, Spinal Injury, etc.
• Lifestyle, i.e. do they work, travel long distances, keep to the house, or participate in sports.
• Economic situation (ability to afford their daily living expenses)
(Ham (1998) and Cruz ( 2002)) SHANGALI RODRICK CONTD…
The Clip-on Tricycle Attachment is an active style hand powered drive allowing:
• Quickly convert the wheelchair into a tricycle
• It helps the user to travel greater distances with less effort,
• Easy to replace or repair and uses many standard bicycle parts.
• Assembling and dissembling for recycling or reuse.
• The tricycle drive, together with the wheelchair, is easy to carry
on most forms of transport. (Kirby and Cooper (2007))
SHANGALI RODRICK METHODOLOGY a) Survey and data collection b) Interviews involves Users, Manufactures,Experts,Centres for disabled peoples Sponsors of disabled peoples for both wheelchair and tricycle, Supplier and TBS Standards, c) Information analysis d) Observations, User’s ,Manufactures and Supplier’s e) Design process/ procedures f) Manufacturing, Testing and Evaluation
SHANGALI RODRICK PROJECT AREA
• The project was conducted at TATCOT in Moshi,
Tanzania.
• Also it involved collaboration and co-operation with
other company or societies, such as KASI in Moshi, DAGE and TDTC, both in Dar-es- salaam.
SHANGALI RODRICK COLLECTED INFORMATION
DAGE: ONE OF THE TRICYCLE DESIGN
SHANGALI RODRICK ANALYSIS
Design Information and Responces
The assessment was to inspect the current state of wheelchair technology from all angles through interviewing the primary parties involved with wheelchair design, manufacturing and users.
SHANGALI RODRICK CONTD…
The results were been grouped in terms of interviewed:
• Individual wheelchair users
• Wheelchair advocacy groups
• Wheelchair manufacturers.
SHANGALI RODRICK A. USER RESPONCE In all, 30 physically disabled people who were interviewed:
Causes of physical disability
• Polio was the most common disability observed. Most polio survivors interviewed contracted the virus early in life.
• Survivors of birth defects and polio, who made up 63% of people interviewed, had been disabled for nearly their whole life.
• In comparison to the spinally injured, who became disabled typically later in life (~20 years old), birth defect and polio survivors had their entire life to acclimatise to being disabled.
SHANGALI RODRICK
Causes of disability
14% 23% Birth Defect Polio
63% Spinal Injury
SHANGALI RODRICK Pre-wheelchair mobility
• As a result of the majority of interviewees becoming disabled early in life with a birth defect or polio, most had to resort to crawling as a means of mobility before obtaining a wheelchair or tricycle.
• 66% of the interviewees were crawling before obtaining their current mobility aid.
SHANGALI RODRICK Travel before current mobility aid
80%
60%
40%
20% No. of Interviewee of No. 0% Crawling Cane Crutches Push cart Means of transportation before current WC/trike
SHANGALI RODRICK CONTD…..
• The average age of obtaining a first wheelchair or tricycle was 15-20 years old.
• As a result, most people who went to school or had a job before the age of 22 were forced to crawl as a means of travel, while others were simply unable to attend school or obtain a job because of distance.
SHANGALI RODRICK Age when first mobility aid obtained
70%
60% 50% 40% 30% 20%
No. of Interviewee of No. 10% 0% 0-20 21-30 31-40 40-49 50+ Aged when first mobility aid obtained
SHANGALI RODRICK
Mobility aid usage after obtaining wheelchair or tricycle
• Most of the interviewees needed to travel multiple kilometers per day, with 50% travelling between 0 to 5km.
• For long distances, a tricycle requires much less power than a wheelchair. As a result, tricycles were observed to be more popular than wheelchairs
SHANGALI RODRICK Daily travel distance
50%
40%
30%
20% No. of Interviewee of No. 10%
0% 0 to 5 Km 6 to 10 11 to 15 Km 16 to Km 19Km >20 km Distance travel to work/ school
SHANGALI RODRICK
Wheelchair or tricycle purchasing ability
• One major problem observed during the assessment was the inability of many people to purchase their own mobility aid.
• Only 17% of those interviewed were able to purchase their own mobility aid
SHANGALI RODRICK Sources of funds for current mobility aid
Chair manufac.
Business/Donation
Hospital
NGO/Church/Mosque
Gov't Who paid for current for WC/trike paid Who Yourself/family
0% 10% 20% 30% 40% 50% 60% 70% No. of Interviewee
SHANGALI RODRICK
Locations of wheelchair/Tricycle repair
• Bicycle shops were the most common location of wheelchair and tricycle repair reported during the assessment. Part availability was a serious issue in how repairable chairs were.
• The most common complaint about chairs was that spare parts are not available.
• Tricycles are easily repaired at bicycle shops because they are primarily built from bicycle parts.
SHANGALI RODRICK Distribution of mobility aid repair locations
Yourself 14% At manufact 23%
Bicycle shop 63%
SHANGALI RODRICK B. Manufacturer Responce
• Decrease prices of WTTC wheelchairs to compete with tricycles. Right now there is a $100US price difference between WTTC chairs and Tanzanian tricycles. UWZ is able to produce wheelchairs for just $140US.
• Use of bicycle parts and outsourcing lowers prices and also makes the wheelchairs and tricycles easier to repair by bicycle workshops.
• The strength of many wheelchair and tricycle designs should be re- calculated to determine if they can sustain stresses caused by environments in developing countries.
SHANGALI RODRICK CONTD ……
• Bearings should be correctly mounted, as to not shorten their life. A wheelchair with tricycle attachment should be investigated as a possible product for WTTC graduates to produce.
SHANGALI RODRICK C. Advocacy Group Responce
• Most of the organizations interviewed do not purchase wheelchairs or tricycles, and instead rely on donations. Those that do buy chairs are reported below, along with details about how many WCs they buy and how much the organizations spend on chairs and tricycles.
• For few organizations are able to purchase chairs, but international NGOs like Lilana funds are willing to subsidize purchases.
• SHANGALI RODRICK
ANALYSIS
• Feedback from current wheelchair and tricycle users, and assessing the pitfalls of current mobility aid technology. • A next-generation wheelchair should be designed in the future. The most versatile type of mobility aid would be a wheelchair with a tricycle attachment. • The tricycle attachment concept was very popular with interviewees and wheelchair workshops. This new type of wheelchair would meet the short and long distance mobility needs of Tanzania’s disabled.
SHANGALI RODRICK CONCEPT 1
SHANGALI RODRICK CONCEPT 2
SHANGALI RODRICK Evaluation and Concept Ranking. The evaluation and ranking of the concepts using Rating and Weighting Matrix Method was through the following criteria; • Easy to manufacture • Low production cost • Reasonable product price • Easy to operate • Simple design • Efficiency • Ergonomics • Aesthetics • Weight • Availability of material
• Safety SHANGALI RODRICK
CONTD…
To fully serve wheelchair users, the following features should be included in the next-generation African wheelchair with tricycle Attachment • 3-wheeled: A three-wheeled design is best suited for the rough terrain of both urban and rural Tanzania. Three wheels are always in contact and kinematically constrained with the ground, making the chair very stable on rough surfaces.
• Foldable frame: For trips longer than what is possible with the tricycle attachment, the wheelchair must be stowable on busses. Allowing the frame to fold gives the chair the functionality of a 3- wheeler with the packability of a folding 4-wheeler.
SHANGALI RODRICK CONTD… • Stowable tricycle attachment: The wheelchair should have an area or fixture on which to stow the tricycle attachment. This area could possibly be on the back of the chair. The rider should have the option of keeping the tricycle attachment affixed to the chair, as there may be situations where leaving it alone might not be safe or feasible.
SHANGALI RODRICK DESIGNS
All the design sketches, parts and assembly was done Under design package , solidwork 2005 and solidwork 2012.
SHANGALI RODRICK MANUFACTURING
SHANGALI RODRICK CONTD…
MAIN FRAME
SHANGALI RODRICK CONTD…
PAINTING
SHANGALI RODRICK
TESTING THE ATTACHMENT TO FIT
SHANGALI RODRICK ATTACHEMENT MOUNTING
SHANGALI RODRICK ELEVATION POINT(TRICYCLE)
SHANGALI RODRICK
Bill of quantity (BOQ)
The bill of material was formulated depend on detail and assembly drawing of various components, table below shows requirement and cost of various components of the designed wheelchair tricycle attachment.
SHANGALI RODRICK Table .Bill of Quantities (BOQ)
S/N Name Specification/Size Quantity Unity Price Amount (T.shs)
1 Used bike frame Gear front frame 2 pc 50,000 100,000 assembly 2 Pedal hub bearing 1 pc 10,000 10,000 assembly 3 pedal 1Pair (L= 170mm) 2 pc 10,000 20,000 4 Bike chain Length (1820 mm) 1 pc 5,000 5,000 5 Bike sprocket 30 teeth 1 pc 5,000 5,000 6 Bike sprocket changer 28,20,12 and 10 1 pc 5,000 5,000 teeth 7 Bolts and nuts M 12x25mm 3 Kg 2,000 6,000 8 Bolts and nut M8x58.1mm 3 Kg 2,000 6,000 9 Tyre 1 pc 10,000 10,000 10 Brake assembly 1 pc 8,000 8,000 11 Round rod 2 pc 20,000 40,000 12 Flat bar 10x2x50 2 pc 15,000 30,000 13 Wheelchair 3 wheeler 1 14 Shaft 2 pc 40,000 80,000 TOTAL COST 325,000/=
SHANGALI RODRICK Cost Estimate of the Designed Wheelchair tricycle attachment Cost estimate of the Wheelchair tricycle attachment is calculated based on the costs incurred to which a profit margin is added. Product costing at TDTC is guided by the following formula From the basic formula, Let A= Contingency (100% of material cost) B= Machine charge (10% of material cost) C= Labour charge (30% of material cost) D= Overhead cost/institutional cost [15% of (A+B+C)] Thus; cost of the pin mill machine will be T.Shs 500,000
SHANGALI RODRICK SHANGALI RODRICK SHANGALI RODRICK Thank you for listening
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