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79.1 million automobiles were produced worldwide in 2021

79 million automobiles = 79 million Bumpers

؜These bumpers were produced just for new cars alone. Not taking into account crashes and replacements!

79% end up in landfills causing metal and plastic pollution.

84 Million pounds of plastic used per year to create new ones.

What is the Material Make Up of the Bumper Industry?

Aluminum 10%

What is the Material Make Up of the Bumper Industry?

Aluminum 10%

Steel 15%

What is the Material Make Up of the Bumper Industry?

Aluminum 10%

Steel 15%

Fiber 20%

What is the Material Make Up of the Bumper Industry?

Plastic 55%

Aluminum 10%

Steel 15%

Fiber 20%

We Should Use Memory Alloys To Decrease the Cost of Bumper Repair

Memory alloys self repair once high temperatures (or pressures) are applied to them.

Using these materials, more costly repairs such as:

1. deep dents

1. severe warping

1. repairing an already damaged bumper

will become much cheaper.

؜Molding A Memory Alloy Is Very Simple

Heating Process:

Break the molecular structure

Forming Process:

Change the structure to what you want.

Cooling Process:

Keep the molecular structure as you want

Nitinol Has Two States

Austenite Phase:

Malleable and returns to original state when heated.

Martensite Phase:

Flexible and solid but doesn't return to set state

It Is Extremely Expensive

100 mm

100 mm

The cost of 1, 100 mm x 100 mm (4in x 4in) nitinol steel plate is

190 $

Simulations

Running the simulation with a simple shape.

؜Setting up collisions, constraints, and forces for simulation.

Results

Corners and the front take most of the stress.

Furthermore, minor dents usually are on the corners as well.

End result showing areas with large amounts of stress.

With the Simulations Done Physical Testing Began

؜Coding a new initial state.

Output once shape is set.

Testing the Force Needed to Pull the Strips

After acquiring the memory alloy strips we wanted we tested each variation.

We clamped them above a ledge then pulled down. During this time we were measuring how far the metal could be bent down and the amount of force needed.

؜A Bow Based Design Is the Most Optimal

Elastic force of bow design: 235.44 N

Force required to bump out a 1.5 cm radius dent:

( 1.5^2 * pi ) * (110) ~ 780 N

Strips of Nitinol Needed:

780/235.44 = 4

Next Steps

؜I need to test the metal strips with an actual sheet of aluminum from a car bumper and see if it can pop a dent out.

Mounting the metal strips such that they use their full potential will be a seperate challenge.

We need to run bumper to bumper simulations as well.

Thanks!

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