Engineering: Engineering Design Process
Defining problems, creating solutions, testing prototypes, and improving designs
Engineering: Engineering Design Process
Defining problems, creating solutions, testing prototypes, and improving designs
Engineering - Grade 9-12
- 1
A school wants to reduce the amount of plastic water bottles used by students. Write a clear engineering problem statement for this challenge. Include the need, the users, and the goal.
A good problem statement does not jump straight to one solution. It describes the problem and who needs help.
A strong problem statement could be: Design a way for high school students to drink water during the school day while reducing single-use plastic bottle waste. The users are the students and school staff, and the goal is to lower plastic waste while keeping water convenient and safe to access. - 2
For the plastic water bottle challenge, list three criteria and three constraints that an engineer should consider.
Possible criteria include that the solution should be easy for students to use, reduce plastic waste, and provide clean drinking water. Possible constraints include a limited budget, available space in the school, and health or safety rules for drinking water. - 3
A team is designing a phone stand for classroom video calls. They create three sketches before choosing one idea. Explain why generating multiple ideas is better than choosing the first idea immediately.
Think about creativity, comparison, and avoiding hidden problems.
Generating multiple ideas is better because it helps the team compare different approaches, notice strengths and weaknesses, and avoid settling too quickly on a weak design. The best solution is often a combination of ideas from several sketches. - 4
A prototype bridge made from craft sticks must hold as much weight as possible while using no more than 50 sticks and no glue other than wood glue. Identify the main criteria and constraints in this situation.
The main criterion is that the bridge should hold as much weight as possible. The constraints are that the bridge may use no more than 50 craft sticks and may use only wood glue as the adhesive. - 5
A student says, 'Our prototype failed, so the design process is over.' Explain why this statement is incorrect.
In engineering, a failed test is often a source of evidence.
The statement is incorrect because failure during testing provides useful information. Engineers use test results to identify what went wrong, improve the design, and test again. Iteration is a normal part of the engineering design process. - 6
A group tests three paper airplane designs. Design A flies 8 m, 10 m, and 9 m. Design B flies 12 m, 7 m, and 11 m. Design C flies 9 m, 9 m, and 10 m. Calculate the average flight distance for each design and identify which design performed best by average distance.
Design A has an average distance of 9 m because (8 + 10 + 9) divided by 3 equals 9. Design B has an average distance of 10 m because (12 + 7 + 11) divided by 3 equals 10. Design C has an average distance of about 9.3 m because (9 + 9 + 10) divided by 3 equals 9.3. Design B performed best by average distance. - 7
In the paper airplane test, Design B had the highest average distance but also had one low trial of 7 m. Explain one reason engineers should look at both average performance and consistency.
A design used in real life often needs to work well more than once.
Engineers should look at both average performance and consistency because a design that sometimes performs very well but sometimes performs poorly may not be reliable. A consistent design may be safer or more predictable, even if its average is slightly lower. - 8
A bike helmet company is developing a new helmet. Describe one way engineers could use a model or simulation before building a full physical prototype.
Engineers could use a computer simulation to model how the helmet absorbs impact during a crash. This would help them compare shapes and materials before spending money on full physical prototypes. - 9
A design team is creating an emergency flashlight for power outages. The flashlight must cost less than $12 to make, last at least 6 hours, and be easy to find in the dark. Propose one design feature that addresses each requirement.
Match each feature to a specific requirement.
To keep the cost below $12, the team could use a simple plastic case and common LED parts. To last at least 6 hours, the flashlight could use energy-efficient LEDs and batteries with enough capacity. To make it easy to find in the dark, the case could include glow-in-the-dark material or a small locator light. - 10
During testing, a prototype emergency flashlight works for only 4 hours instead of the required 6 hours. Write a specific design change and explain how the team should test whether the change works.
The team could replace the battery with a higher-capacity battery or use a more efficient LED. To test the change, they should fully charge or install fresh batteries, turn the flashlight on, record how long it stays bright enough to use, and compare the result to the 6-hour requirement. - 11
A team is designing a low-cost water filter. They plan to test water before and after filtering by measuring cloudiness. Identify the independent variable, dependent variable, and one controlled variable for this test.
The independent variable is what the team changes, and the dependent variable is what they measure.
The independent variable is the filter design or filter material being tested. The dependent variable is the cloudiness of the water after filtering. One controlled variable could be the amount of water filtered, the starting cloudiness of the water, or the time allowed for filtering. - 12
A design brief says a water filter should remove particles, cost less than $5, and be made from materials available at home. Explain why a design brief is useful before building begins.
A design brief is useful because it summarizes the problem, goals, criteria, and constraints before building begins. It helps the team stay focused, compare design ideas fairly, and avoid wasting time on solutions that do not meet the requirements. - 13
A team receives feedback that their backpack design has comfortable straps but not enough pockets. Explain how user feedback can change the next iteration of a design.
Iteration means improving a design based on evidence and feedback.
User feedback can guide the next iteration by showing which parts of the design work well and which parts need improvement. In this case, the team should keep the comfortable strap design and revise the backpack to include more useful pockets. - 14
An engineering team must choose between two materials for a solar oven. Material X is cheap and lightweight but loses heat quickly. Material Y costs more and is heavier but keeps heat in better. Explain how the team should make a decision using trade-offs.
The team should compare the materials against the project criteria and constraints. If heat retention is the most important criterion and the budget allows it, Material Y may be better. If low cost and portability are more important, Material X may be better. The best choice depends on which trade-offs best meet the design goals. - 15
Put these engineering design process steps in a logical order and explain your order: test the prototype, define the problem, brainstorm solutions, improve the design, build a prototype, research the problem.
The design process is often repeated after testing.
A logical order is: define the problem, research the problem, brainstorm solutions, build a prototype, test the prototype, and improve the design. This order works because engineers first need to understand the need and background information, then create and test a possible solution, and then use evidence to make improvements.