Unit 8 Advanced Computer Modeling

Unit 8 Advanced Computer Modeling Overview Preface Parameters-based computer modeling programs utilize the powerful mathematical capabilities of computers to store, maintain, modify, and update vast quantities of information. CAD solid modeling software bridge design intent and the resulting geometry by giving an engineer an opportunity to establish design parameters. Parameters establish the relationships between the geometric elements of a design and allow the computer to make significant modifications to multiple areas of a design simultaneously. This is what separates a solid modeling program from simpler CAD programs. Coupled with the ability to share design information through the internet with teammates and customers across the world, parameter-based computer modeling has proven itself to be a significant design tool.

Most devices are comprised of several components that work together. CAD solid modeling programs allow designers to simulate the interactions between the components of a design to forecast how the design will behave when it is actually manufactured. Students will use the computer to determine if interferences exist between assembled components. Once students have experienced assembling models, they may animate the models by driving their assembly constraints to verify the models’ functional characteristics. Students may also learn how to use algebraic equations to drive multiple constraints simultaneously.

It is important that the parallels between CAD operations and manufacturing operations be identified as students learn how objects are created in a virtual environment. After all, designing a virtual object that cannot be built is a major problem.

This unit presents many of the 3D functions used to develop individual and assembly CAD solid models. Students will use these modeling skills to develop their design solutions to various projects and problems throughout the rest of the course. The goal of this lesson is to provide an opportunity for students to acquire the knowledge and experience to effectively utilize CAD as a design tool in an engineering design process.

Understandings Students will understand that …  U1 – Parametric computer aided design (CAD) software packages facilitate 3D virtual modeling of parts and assemblies using parameters, such as geometric constraints (the relationships between geometric entities) as well as numeric constraints (dimensions) used to determine the shape and size of geometry and models.

 U2 – A parametic numeric constraint (dimension) can be represented by a function (equation) that mathimatically describes the relationship between that dimension and other related dimension(s).

© 2012 Project Lead The Way, Inc. Introduction to Engineering Design Unit 8 Advanced Computer Modeling Overview – Page 1  U1 (Unit1) – Technical drawings convey information according to an established set of drawing practices which allow for detailed and universal interpretation of the drawing.  U4 (unit 1) – The style of the engineering graphics and the type of drawings views used teo detail an object vary depending upon the intended use of the graphic.

Knowledge and Skills KNOWLEDGE: Students will …  K1 – Identify, define, and explain the proper use of an auxiliary view in technical drawing.

SKILLS: Students will …  S1 – Use advanced modeling features to create three-dimensional solid models of complex parts and assemblies within CAD and with little guidance given the actual part using appropriate geometric and dimensional constraints.  S2 – Formulate equations and inequalities to represent relationships between quantities.  S3 – Using a CAD application, create relationships among part features and dimensions using parametric formulas.  S4 – Create an exploded assembly view of a multip-part product. Identify each component of the assembly with identification numbers and create a parts list to detail each component using CAD.  S5 – Perform a peer review of technical drawings and offer constructive feedback based on standard engineering practices.  S6 (Optional) – Hand sketch an auxiliary view in the correct orientation to fully detail an object or part given the actual object, a detailed verbal description of the object, a pictorial view of the object, or a set of orthographic projections.  S7 (Optional) – Generate an auxiliary view using CAD according to standard engineering practice.

Essential Questions  EQ1 – Are working drawings always necessary in order to communicate the design of a consumer product? Justify your answer.

 EQ2 – Animated assemblies are not typically included as part of the technical documentation of a design. How can 3D animated assembly models of an object or a proposed design be used in the design process? Beyond the design process?

Please visit the PLTW Standards and Objectives Tool for the most up to date Standards Alignment http://alignment.pltw.org Day-by-Day Plans Time: 12 days

Day 1 2 3 4 5 6 7 8 9 10 11 12 …

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A8.3 (Optional ) A8.4

 The teacher will present Objectives, Concepts, Key Terms, Essential Questions, and provide a lesson overview.  (Optional) The teacher may present Work Points, Work Axes, and Work Planes.ppt (which was previously presented in Unit 5) while Day students take notes. 1 - 2  The teacher will introduce and distribute Project 8.1 Model a Button Maker.  (Optional) The teacher may assign Activity 8.1a Model a Miniature Train as an optional or alternate activity to provide more practice or differentiate instruction.  The teacher will introduce and distribute Activity 8.2 Parametric Constraints.  The teacher will present Parametric Modeling.ppt.  Students will take notes in their journals. Day  Students will complete Project 8.1 Parametric Constraints. 3 - 4  The teacher will assess student work using Activity 8.2 Parametric Constraints Answer Key.  Students will continue working on Project 8.1 Model a Button Maker.  (Optional) The teacher may assign Activity 8.3a Parametric Constraints Practice (Optional).

© 2012 Project Lead The Way, Inc. Introduction to Engineering Design Unit 8 Advanced Computer Modeling Overview – Page 3  CFU: When would you use parametric formulas to define a relationship between dimensions of an object?  The teacher will present Auxiliary Views.ppt while students take Opti notes. onal  The teacher will introduce and distribute Activity 8.3 Auxiliary Views (2 (Optional). Day  Students will finish work on Activity 8.3 Auxiliary Views (Optional). s)  The teacher will assess student work using Activity 8.3 Auxiliary Views Answer Key.  Students will continue working on Project 8.1 Model a Button Maker.  CFU: Compare a section view and an auxiliary view, and explain the attributes of a part for which each view is appropriate to use when detailing the part. Day  Students will continue working on Project 8.1 Model Button Maker. 5 - 8  (Optional) The teacher will assign Activity 8.1b Model a Miniature Train Change Orders (if students have been assigned Project 8.1a Model a Miniature Train)  The teacher will present Exploded CAD Assembly Models.ppt. The teacher may want to demonstrate this to students instead of showing the presentation. Day  Students will take notes. s 9 -  The teacher will demonstrate how to explode an assembly using the 10 Project 8.1 Model Button Maker.  Students will explode their Button Maker (or Miniature Train) Model,  The teacher will assist the students as needed.  CFU: How can assembly models, exploded assemblies, and animated assemblies of an object or a proposed design be used in the design process? Beyond the design process?  Optional: The teacher will present Animating Assembly Models and Opti Exporting Video.ppt. The teacher may want to demonstrate this to onal students instead of showing the presentation. ( 2  Students will take notes. Day  The teacher will demonstrate how to animate an assembly using the s) Project 8.1 Model a Button Maker (or Miniature Train).  Students will animate their Button Maker Model 8.1b Model Arbor (or Model Miniature Train).  The teacher will assist students as needed.

© 2012 Project Lead The Way, Inc. Introduction to Engineering Design Unit 8 Advanced Computer Modeling Overview – Page 4  CFU: How do you decide what to include in a set of working drawings? What views are needed? What other information is important?  The teacher will introduce and distribute Activity 8.4 Working Day Drawings (Button Maker) and Activity 8.4 Part Drawing Rubric. s 11  Students will begin work on Activity 8.4 Working Drawings (Button - 12 Maker).  The teacher will demonstrate the application of balloons and a parts list to an exploded isometric pictorial assembly drawing of the Button Maker and the creation of a sectioned assembly view.  Students will complete the selected Activity 8.4 Working Drawings.  The teacher will distribute Activity 8.5 Instant Challenge: Air Vehicle. (1  The students will complete Activity 8.5 Instant Challenge: Air Vehicle. Day)  The teacher will assess student work using the scoring criteria listed in the Instant Challenge.