1.1 ENGINEERING DESIGN DEEP DIVE VIDEOS
View the entire “Deep Dive” episode by using the following links.
http://www.youtube.com/watch?feature=player_detailpage&v=M66ZU2PCIcM
http://www.youtube.com/watch?feature=player_detailpage&v=pVZ8pmkg1do
http://www.youtube.com/watch?feature=player_detailpage&v=nyugyrCQTuw
Please answer the following questions based on the videos and your understanding
http://www.youtube.com/watch?feature=player_detailpage&v=M66ZU2PCIcM
http://www.youtube.com/watch?feature=player_detailpage&v=pVZ8pmkg1do
http://www.youtube.com/watch?feature=player_detailpage&v=nyugyrCQTuw
Please answer the following questions based on the videos and your understanding
of the Engineering Design Process (EDP).
1. What was the problem the engineers at IDEO were asked to solve?
To redesign the shopping cart in 5 days.
2. Name two constraints that they had to deal with.
-They had 5 days to do the job
-They had to completely redesign the shopping cart.
3. What were two of the major concerns/issues the teams discovered from their research?
-Shoppers, besides the professional shoppers, do not like to let go of the cart
-The seat for children is not safe.
4. IDEO uses several methods, processes and ideas to generate alternative solutions. What two principles or approaches appealed to you the most? Why?
-Having a fun environment to work in. It is nice because they get to make ideas quickly and also have fun at the same time.
-Building on wild ideas. Wild ideas are very good but they are not realistic, and so to bring them to real life you have to build on them and not reject them.
5. How were the possible solutions prototyped and tested?
The team split up and worked overnight in shifts.
6. Was there a redesign step in the IDEO project? What was the final outcome?
1. What was the problem the engineers at IDEO were asked to solve?
To redesign the shopping cart in 5 days.
2. Name two constraints that they had to deal with.
-They had 5 days to do the job
-They had to completely redesign the shopping cart.
3. What were two of the major concerns/issues the teams discovered from their research?
-Shoppers, besides the professional shoppers, do not like to let go of the cart
-The seat for children is not safe.
4. IDEO uses several methods, processes and ideas to generate alternative solutions. What two principles or approaches appealed to you the most? Why?
-Having a fun environment to work in. It is nice because they get to make ideas quickly and also have fun at the same time.
-Building on wild ideas. Wild ideas are very good but they are not realistic, and so to bring them to real life you have to build on them and not reject them.
5. How were the possible solutions prototyped and tested?
The team split up and worked overnight in shifts.
6. Was there a redesign step in the IDEO project? What was the final outcome?
Yes. The final outcome was a combination of bits and pieces from the first prototypes.
- Responsible for all documentation and “care” of the mousetrap. - Insures that all tasks are completed and documented on time.
- Has final say on any issue that cannot be settled by consensus
Drivetrain Engineer (IC of the Analysis) - Ian Hong
- Responsible for developing system to transfer energy from the “engine” to the wheels. - Insures proper testing and documentation of all drivetrain components.
Wheel Engineer (IC of the Construction and Testing) - Itmam Azwad
- responsible for wheel choice and design
- sources materials for wheels
- works with Drivetrain Engineer to determine wheel-to-axle ratio and attachment
Chassis Engineer (IC of timekeeping and planning) - Chan Kuang Seng
- responsible for the look and function of the body (chassis) of the car
- sources all materials for the chassis
- works with Drivetrain and Wheel Engineers to insure function and look of wheels and drivetrain components
1.2 Assignment of roles
Project Manager (IC of the report and presentation) - Ryan Goh- Responsible for all documentation and “care” of the mousetrap. - Insures that all tasks are completed and documented on time.
- Has final say on any issue that cannot be settled by consensus
Drivetrain Engineer (IC of the Analysis) - Ian Hong
- Responsible for developing system to transfer energy from the “engine” to the wheels. - Insures proper testing and documentation of all drivetrain components.
Wheel Engineer (IC of the Construction and Testing) - Itmam Azwad
- responsible for wheel choice and design
- sources materials for wheels
- works with Drivetrain Engineer to determine wheel-to-axle ratio and attachment
Chassis Engineer (IC of timekeeping and planning) - Chan Kuang Seng
- responsible for the look and function of the body (chassis) of the car
- sources all materials for the chassis
- works with Drivetrain and Wheel Engineers to insure function and look of wheels and drivetrain components
1.3 Brainstorming
Engineering Goal:
Develop a MouseTrap Car with the following specifications:
Idea 1: 3 Wheels(less weight than 4 wheels), powered by string connected to the trap. Use of recycled plastic for body.
Idea 2: 3 Wheels 2 in front 1 at back, connecting 2 rubberbands from the trap to the axel. Use of Chopsticks for body.
Idea 3: Use of string to connect a 1-way turning device so that when the string runs out the car still can keep on moving.
Develop a MouseTrap Car with the following specifications:
-
(a) Uses only the MouseTrap provided as the only energy source
-
(b) Has a maximum length of 30 cm, width of 10 cm, and a height of 10 cm
-
(c) Can travel a minimum distance of 5 meters carrying an egg (the egg will be
provided by the teacher)
-
(d) All time-lines have to be adhered.
Idea 1: 3 Wheels(less weight than 4 wheels), powered by string connected to the trap. Use of recycled plastic for body.
Idea 2: 3 Wheels 2 in front 1 at back, connecting 2 rubberbands from the trap to the axel. Use of Chopsticks for body.
Idea 3: Use of string to connect a 1-way turning device so that when the string runs out the car still can keep on moving.
1.4 Decision Making Matrix
Step 1: List Criteria (9 criteria)
· weight · size · appearance · time to produce · cost to produce · ease of use
· availability of materials · environmental impact · safety
Evaluating Alternatives Rubric
a) Your team should make a list of all the criteria you can think of to compare your design solutions. In other words, what are the important design considerations? Some possibilities are: Weight, Size, Time constraints, Materials
b) Make a list of eight criteria on the back of this page or another sheet of paper.
Step 2: Assign Priority Values to Criteria
a) Complete the interaction matrix (page 2) by listing the criteria both in rows down the left and columns across the top. Don’t worry about filling out the “ROW TOTAL,” “COLUMN TOTAL,” or “NORMALIZED VALUE” yet.
b) Now choose a facilitator within your team, and have this person poll the entire team for their opinions of the relative importance of one criterion over another. For example, the first blank cell on the top left tallies the number of people who feel that Criterion 1 is more important than Criterion 2. Let’s say you have five people in your team, and three people feel that Criterion 1 is more important than Criterion 2. Then you would write the number “3” in this first blank cell on the top left. You would then write a “2” in the off-diagonal cell—the one that ranks Criterion 2 against Criterion 1.
c) Add the number across the rows for each criterion and write this number in the “ROW TOTAL” cell.
d) Add the “ROW TOTAL” numbers down the column to find the “COLUMN TOTAL.”
Step 3: Normalize the Priority Values
a) To get a better feel for the relative priority values, you can “normalize” the values, which means to calculate each value as a proportion of a total that equals 1.
b) To normalize the priority values, divide each “ROW TOTAL” by the “COLUMN TOTAL” and write this number in the corresponding “NORMALIZED VALUE” cell.
Step 4: Compare Alternative Designs
a) Order the normalized criteria values from largest to smallest. This puts the most important criteria at the top of the list.
b) Write each criterion and its corresponding normalized criteria value in the decision matrix (page 4).
c) Now, rank each alternative design concept according to how well the group feels that concept could satisfy each of the design criteria identified. Use a consistent scale (for example 0 – 5). A ranking of 0 means that the team feels the design concepts does not meet the criterion at all. A 5 means that the team feels the design concepts meets the criterion perfectly.
d) Write these ranked values in the gray cells below each design alternative. e) Multiply each ranked value by the normalized criterion value and write this
number to the right of the ranked value for each design alternative.
f) Sum these multiplied values and write them in the corresponding ―TOTALǁ‖ cell. Step Five:
Analyze Results
a) The design alternative with the highest value (as shown in the ―TOTALS column) is
the alternative that best meets the selected criteria. Design alternatives with significantly lower values can be discarded. The design alternative with the highest score may be selected, or you can select the alternative that received the highest score for the majority of the categories.
b) Which is the design alternative with the highest value? c) Which idea will you proceed to design?
Step 1: List Criteria (9 criteria)
· weight · size · appearance · time to produce · cost to produce · ease of use
· availability of materials · environmental impact · safety
Evaluating Alternatives Rubric
a) Your team should make a list of all the criteria you can think of to compare your design solutions. In other words, what are the important design considerations? Some possibilities are: Weight, Size, Time constraints, Materials
b) Make a list of eight criteria on the back of this page or another sheet of paper.
Step 2: Assign Priority Values to Criteria
a) Complete the interaction matrix (page 2) by listing the criteria both in rows down the left and columns across the top. Don’t worry about filling out the “ROW TOTAL,” “COLUMN TOTAL,” or “NORMALIZED VALUE” yet.
b) Now choose a facilitator within your team, and have this person poll the entire team for their opinions of the relative importance of one criterion over another. For example, the first blank cell on the top left tallies the number of people who feel that Criterion 1 is more important than Criterion 2. Let’s say you have five people in your team, and three people feel that Criterion 1 is more important than Criterion 2. Then you would write the number “3” in this first blank cell on the top left. You would then write a “2” in the off-diagonal cell—the one that ranks Criterion 2 against Criterion 1.
c) Add the number across the rows for each criterion and write this number in the “ROW TOTAL” cell.
d) Add the “ROW TOTAL” numbers down the column to find the “COLUMN TOTAL.”
Step 3: Normalize the Priority Values
a) To get a better feel for the relative priority values, you can “normalize” the values, which means to calculate each value as a proportion of a total that equals 1.
b) To normalize the priority values, divide each “ROW TOTAL” by the “COLUMN TOTAL” and write this number in the corresponding “NORMALIZED VALUE” cell.
Step 4: Compare Alternative Designs
a) Order the normalized criteria values from largest to smallest. This puts the most important criteria at the top of the list.
b) Write each criterion and its corresponding normalized criteria value in the decision matrix (page 4).
c) Now, rank each alternative design concept according to how well the group feels that concept could satisfy each of the design criteria identified. Use a consistent scale (for example 0 – 5). A ranking of 0 means that the team feels the design concepts does not meet the criterion at all. A 5 means that the team feels the design concepts meets the criterion perfectly.
d) Write these ranked values in the gray cells below each design alternative. e) Multiply each ranked value by the normalized criterion value and write this
number to the right of the ranked value for each design alternative.
f) Sum these multiplied values and write them in the corresponding ―TOTALǁ‖ cell. Step Five:
Analyze Results
a) The design alternative with the highest value (as shown in the ―TOTALS column) is
the alternative that best meets the selected criteria. Design alternatives with significantly lower values can be discarded. The design alternative with the highest score may be selected, or you can select the alternative that received the highest score for the majority of the categories.
b) Which is the design alternative with the highest value? c) Which idea will you proceed to design?
1.5 Design Rationale and Notes
Notes should be kept for every key component of the car and there should be a
clear justification/discussion of all design issues and decisions in terms of the
physics involved. You may use this form or feel free to design a different format
that works for your group. It does not have to perfectly laid out since it is a
working document, but it should be easy to follow and reference. You may use
sketches to illustrate design issues and characteristics.
Key components should include the following as a minimum. Your group may have more.
Wheels: CDs, 3 of them to minimise friction.
Lever arm: Metal
Chassis Material: The mousetrap itself. If not enough, use a piece of balsa wood connected by glue.
Chassis Shape: Triangle shaped, 2 wheels in front, one behind for stability. Smallest possible size to reduce weight.
Location of Mousetrap Axles: Connected to the front two wheels.
String type and attachment: Use of cotton twine. Attatched via one-way turning gate used in hand-power generated flashlights.
1.6 Materials used
Material: CDs (3pcs)
Where it is used: Wheels
Reason: Large wheels for faster movement(lower revolutions needed to cover same amount of distance).
Material: Balsa Wood(1 Block)
Where it is used: Chassis
Reason: Lightweight and strong.
Material: One-way turning gate (1pc)
Where it is used: Axel
Reason: To make sure wheels don't turn backwards after string runs out.
Material: Wooden Chopsticks(2)
Where it is used: Axels
Reason: Lightweight and readily available.
Key components should include the following as a minimum. Your group may have more.
Wheels: CDs, 3 of them to minimise friction.
Lever arm: Metal
Chassis Material: The mousetrap itself. If not enough, use a piece of balsa wood connected by glue.
Chassis Shape: Triangle shaped, 2 wheels in front, one behind for stability. Smallest possible size to reduce weight.
Location of Mousetrap Axles: Connected to the front two wheels.
String type and attachment: Use of cotton twine. Attatched via one-way turning gate used in hand-power generated flashlights.
1.6 Materials used
Material: CDs (3pcs)
Where it is used: Wheels
Reason: Large wheels for faster movement(lower revolutions needed to cover same amount of distance).
Material: Balsa Wood(1 Block)
Where it is used: Chassis
Reason: Lightweight and strong.
Material: One-way turning gate (1pc)
Where it is used: Axel
Reason: To make sure wheels don't turn backwards after string runs out.
Where it is used: Axels
Reason: Lightweight and readily available.
1.7 Preliminary Sketch (Using Google Sketchup)
No comments:
Post a Comment