Absorbing the Force from an Accident through an Impact Attenuator
Location
CSU 201
Start Date
5-4-2010 1:00 PM
End Date
5-4-2010 3:00 PM
Student's Major
Automotive and Manufacturing Engineering Technology
Student's College
Science, Engineering and Technology
Mentor's Name
Gary Mead
Mentor's Department
Automotive and Manufacturing Engineering Technology
Mentor's College
Science, Engineering and Technology
Description
An impact attenuator is a deformable, energy absorbing safety device required for the Formula SAE (Society of Automotive Engineering) competition. The rules define that the attenuator must decelerate a frontal impact from a 661 lb vehicle run into a non-yielding impact barrier at a velocity of 23 ft/sec. The average vehicle deceleration must not exceed a force greater than 20 g’s, with a peak deceleration less than or equal to a force of 40 g’s. To determine the best energy absorbing material, factors like cost, weight and strength were taken into consideration. The two materials that were selected for testing were aluminum honeycomb and polystyrene high density foam. Calculations were done to determine what sizes of material would be sufficient to dissipate the energy. From these calculations, four foam pieces of varying sizes were selected along with one aluminum honeycomb piece. Testing had to be done to prove the calculations and determine which material and size would meet the Formula SAE rules while having the best cost to weight ratio. To do this, an apparatus was designed that held the attenuator in a material testing machine called a MTS. The MTS crushed the attenuator samples and registered the force on a computer. The force to crush each piece was collected and graphed. From this data, size and material were determined. After this, a decision was made on which material to use before making it and attaching it to the car.
Absorbing the Force from an Accident through an Impact Attenuator
CSU 201
An impact attenuator is a deformable, energy absorbing safety device required for the Formula SAE (Society of Automotive Engineering) competition. The rules define that the attenuator must decelerate a frontal impact from a 661 lb vehicle run into a non-yielding impact barrier at a velocity of 23 ft/sec. The average vehicle deceleration must not exceed a force greater than 20 g’s, with a peak deceleration less than or equal to a force of 40 g’s. To determine the best energy absorbing material, factors like cost, weight and strength were taken into consideration. The two materials that were selected for testing were aluminum honeycomb and polystyrene high density foam. Calculations were done to determine what sizes of material would be sufficient to dissipate the energy. From these calculations, four foam pieces of varying sizes were selected along with one aluminum honeycomb piece. Testing had to be done to prove the calculations and determine which material and size would meet the Formula SAE rules while having the best cost to weight ratio. To do this, an apparatus was designed that held the attenuator in a material testing machine called a MTS. The MTS crushed the attenuator samples and registered the force on a computer. The force to crush each piece was collected and graphed. From this data, size and material were determined. After this, a decision was made on which material to use before making it and attaching it to the car.
Recommended Citation
Bruns, Eric and Chris Larson. "Absorbing the Force from an Accident through an Impact Attenuator." Undergraduate Research Symposium, Mankato, MN, April 5, 2010.
https://cornerstone.lib.mnsu.edu/urs/2010/oral-session-05/2
