Unit D Section 4 Introduction How Design Affects Safety
Completion requirements
Section 4: Building safe and sturdy structures requires careful design.
Unit D: Section 4 – Introduction
Figure D.S.4.1 – Lots of space between cars means more time to stop, which might prevent collisions.
Figure D.S.4.2 – The crumple zone is crushed first in a car crash.
Vehicle Safety Features
Safety is the most important consideration for engineers when they design vehicles. Engineers must design cars so that people are as safe as possible if the cars crash.
Drivers can avoid many car collisions. Following the rules of the road, staying at the speed limits, slowing in poor weather conditions, and leaving safe distances between vehicles are all safe driving habits.
Safety is the most important consideration for engineers when they design vehicles. Engineers must design cars so that people are as safe as possible if the cars crash.
Drivers can avoid many car collisions. Following the rules of the road, staying at the speed limits, slowing in poor weather conditions, and leaving safe distances between vehicles are all safe driving habits.
However, crashes occur, which is why engineers put safety features in car designs.
Crumple zones are built into the front and back of most modern vehicles. The crumple zone is designed to crush, flex, and absorb energy under the applied force of a crash.
In this way, the crumple zone reduces the amount of force transferred directly to the passengers. A stiff and rigid passenger compartment that resists crushing and deformation works with the crumple zones to prevent or reduce injuries in crashes.
Airbags inflate very quickly during a crash. Airbags prevent passengers heads from hitting the steering wheel or the windshield.
Seatbelts stop passengers from flying through the windshield, bouncing around within the car, or being thrown from the car during a collision. The law requires everyone to wear a seatbelt while riding in a vehicle.
Crumple zones are built into the front and back of most modern vehicles. The crumple zone is designed to crush, flex, and absorb energy under the applied force of a crash.
In this way, the crumple zone reduces the amount of force transferred directly to the passengers. A stiff and rigid passenger compartment that resists crushing and deformation works with the crumple zones to prevent or reduce injuries in crashes.
Airbags inflate very quickly during a crash. Airbags prevent passengers heads from hitting the steering wheel or the windshield.
Seatbelts stop passengers from flying through the windshield, bouncing around within the car, or being thrown from the car during a collision. The law requires everyone to wear a seatbelt while riding in a vehicle.
Figure D.S.4.3 – When a car stops suddenly, an airbag pops out of the steering wheel.
Figure D.S.4.4 – Wearing a seatbelt is important whenever you are riding in a car -- and it is a legal requirement.
Figure D.S.4.5 – Crash tests are done to observe how design changes help protect passengers. Photo by
Brady Holt.
Watch More
Wearing Seat Belts
This video shows some test car crashes with crash test dummies. Watch what happens to people in a car collision when they do not wear seat belts.
This video shows some test car crashes with crash test dummies. Watch what happens to people in a car collision when they do not wear seat belts.
Safe Small Cars
Small cars use less gas than big cars do to travel a distance. This means they are cheaper to operate and better for the environment. Although the design of small cars is not the best for driving on gravel roads and unplowed winter roads, they are effective for driving in towns and cities. Some people worry that small cars are not very safe to drive.
Smart Cars, such as the one in Figure Figure D.S.4.6, are very tiny cars that hold two passengers. The car has a very small hood so the engine is located in the back of the car. Smart Cars are much more sturdy than they appear because their design includes a rigid steel cage with very strong joints.
Small cars use less gas than big cars do to travel a distance. This means they are cheaper to operate and better for the environment. Although the design of small cars is not the best for driving on gravel roads and unplowed winter roads, they are effective for driving in towns and cities. Some people worry that small cars are not very safe to drive.
Smart Cars, such as the one in Figure Figure D.S.4.6, are very tiny cars that hold two passengers. The car has a very small hood so the engine is located in the back of the car. Smart Cars are much more sturdy than they appear because their design includes a rigid steel cage with very strong joints.
Figure D.S.4.6 – A Smart Car has a very small hood and trunk.
Watch More
Smart Car Design
Watch this video to see how a Smart Car stands up to high-speed crash testing.
Watch this video to see how a Smart Car stands up to high-speed crash testing.
In this section, you will learn about how structures must be designed carefully so they are safe and last for a long time.
Words to Think About:
Words to Think About:
Check the word cloud below. It pictures important words that you will use in this section. Watch for these words and combinations of them. When they are highlighted, you can click them to learn more about their meanings.
Check the word cloud below. It pictures important words that you will use in this section. Watch for these words and combinations of them. When they are highlighted, you can click them to learn more about their meanings.
Lessons in This Section
Lesson D15: Design for Safety
Key Question – How are structures designed to be safe?
Lesson D16: Building to Survive Disasters
Key Question – What are some design features that make buildings stay standing in natural disasters?
Lesson D17: Improving Materials and Structures
Key Question – How are materials and structures improved over time?
Reading and Materials for This Section
Science in Action 7
Reading: Pages 324–338
Materials Lists for Unit:
