1. ME/MECA 238A - Mechanical/Mechatronic Design Project I
Course notes prepared by G.A. Kallio, based on The Mechanical Design Process, by D.G. Ullman
ME/MECA 238A

2. I. Introduction to the Engineering Design Process
Reading: Ullman, Ch. 1-4
ME/MECA 238A

3. What is Engineering Design?
Solving a problem that
is not fully-defined in terms of its requirements
has a multitude of satisfactory solutions
requires creativity and engineering knowledge in generating and evaluating solutions (iterative process)
usually results in a piece of working hardware
ME/MECA 238A

4. Textbook Design vs. Real Design
Textbook design: “What size SAE grade 5 bolt is required to fasten two pieces of 1045 sheet steel, each 4 mm thick and 6 cm wide, which are lapped and loaded with 100 N?”
Real design: “ Design a joint to fasten two pieces of 1045 sheet steel, each 4 mm thick and 6 cm wide, which are lapped and loaded with 100 N.”
ME/MECA 238A

5. Measuring Effective Design
Cost Quality Time
(cheaper) (better) (faster)
The cost of designing is small but design has a large effect on manufacturing cost, overall product quality and time-to-market (Figures 1.2, 1.3)
ME/MECA 238A

6. Measuring Effective Design, cont.
Product cost is committed early in the design process and spent late in the process (Figure 1.4)
Changes made early in design process are more cost-effective than those made later (Figure 1.6)
ME/MECA 238A

7. This Course … Focuses on product design, where
the product solves a problem, or fulfills a genuine need
there is an identifiable customer
there are specific customer requirements
the product requires engineering design
the product will be manufactured and tested as a prototype
ME/MECA 238A

8. Life of a Product Product development Production and delivery Use
End of life
(Figure 1.8)
ME/MECA 238A

9. Concurrent Design
Concurrent, or simultaneous, design has replaced the outdated “over-the-wall” design method (Figure 1.7)
Most important feature: simultaneous development of the product design and manufacturing process
ME/MECA 238A

10. Concurrent Design, cont.
Design for “X” (DFX)
X = M (Manufacturability)
X = Q (Quality)
X = A (Assembly)
X = E (Environment)
X = R (Reliability)
X = S (Safety and Serviceability)
ME/MECA 238A

11. The Design Paradox
As the design process progresses, you gain knowledge but you lose freedom to use what you know (Figure 1.11)
Time and cost normally drive the design project, so there is rarely an opportunity to start over or to redo a design
ME/MECA 238A

12. Types of Design Conceptual design Selection design
Configuration design (packaging)
Parametric design
Original design
Redesign
ME/MECA 238A

13. Design Teams & Personalities
Extrovert vs. Introvert
Fact- vs. possibility-oriented
Objective vs. subjective
Decisive vs. flexible
ME/MECA 238A

14. Design Team Goal Solving a problem through: Collaboration Compromise
Consensus
Communication
Committment
ME/MECA 238A

15. Documentation
Each team member must maintain a notebook (logbook) to document entire project development
Bring notebook to all team and advisory meetings
Notebook must be bound – no looseleaf pages; each completed page dated with your initials
ME/MECA 238A

16. Overview of the Design Process
Establish a need
Develop project plan
Determine engineering specifications
Develop concepts
Develop product
ME/MECA 238A

17. Develop Project Plan (Ch. 5)
Form design teams
Identify tasks & objectives
Estimate personnel, time, and other resources needed for each task
Develop a task sequence
Estimate costs
ME/MECA 238A

18. Determine Engineering Specifications (Ch. 6)
Identify the customers
Determine customer needs (marketing)
Determine relative importance of needs
Evaluate competition & current customer satisfaction
Convert customer requirements to engineering specifications
ME/MECA 238A

19. Develop Concepts (Ch. 7-8)
Functional decomposition
Generate concepts for each function
Evaluate concepts
Product safety & liability
ME/MECA 238A

20. Develop Product (Ch. 9-12) Generate components DFX
Based upon spatial, strength, power, thermal, temporal, acoustic, etc. constraints
DFX
Materials & fabrication selection
Modeling & simulation
Prepare drawings
ME/MECA 238A