Head Drop Airbag Demonstration

Autoliv
Breakneck Engineering

Project Description

The Autoliv head drop airbag apparatus is designed for demonstration to audiences ranging from K-12 STEM fairs to professional career fairs.

The purpose of this project was to update and improve the existing system to streamline and simplify the demonstration process

Sub-systems:

Lever Arm System:

Lever Arm System

All components related directly to the physical drop of the head

  • Lever bar
  • Head form
  • Accelerometer
  • Electromagnet
  • Limit switch and mount
  • Spring neck system

Pressure System:

Pressure System

All components connected to the compressive system

  • Compressor
  • Hoses
  • Valves and hard connectors
  • Solenoid
  • Pressure sensor
  • Airbag
  • Printed caps

Frame:

frame

Hardware and components of external frame

  • T-bar
  • Steel plate
  • Dampening Foam
  • Cap holder
  • Rubber feet

Electronics:

electronics

The electrical system of the apparatus

  • Arduino
  • H-bridge
  • Wiring
  • LED light
  • Computer
  • Code

Design Description

before and after design labeled

Physical Changes:

  1. Airbag Venting
  2. Release Mechanisms
  3. Airbag Fastening
  4. Processorto Arduino
  5. Accelerometer and Mount
  6. Physical Plugin Complexity
  7. Wire Routing & Consolidation
  8. Pressure Storage/Inflation System

Computerized Changes:

  1. Arduino Code
    • Airbag fill time stabilization/customizability
    • Reliability
  2. Graphical User Interface
    • Improved display
    • 'Demonstration' menu

Features Added:

  1. Expressive Light Display
  2. Sound Suppression
  3. Processor Case/Mount
  4. Backwards Compatibility
  5. Pressure Valve
  6. "Hard Path" Pressure System

Performance & Testing:

autoliv graph one
autoliv graph two
Input Output
Test # Time Delay (s) Pressure (psi) Max Accel (G)
1 -1 32.9 26.64
2 -1 32.9 27.25
3 -1 32.9 26.69
4 -1 32.9 29.87
5 -1 32.9 26.07
6 -1 32.9 25.73
7 -1 32.9 25.26
8 -1 32.9 26.97
Mean 26.81
Std. Dev. 1.401152587

Conclusion

Improvements Made:

improvements made
  • Simplification
  • Professional Looking
  • Halved connection points
  • Durability
  • Aesthetics
  • Interactive interface and display
  • Repeatability
  • Reliability
  • Improved venting and changeability
  • New accelerometer
  • Compressor implementation
  • Decreased vibration and impact
  • Code debugged based on head drop test results
  • Testing for output consistencyunder constanttest conditions

Future Work:

  • Electronic pressure valve
  • Head cover
  • Carrying Case
  • T-slot brackets
  • Additional indicators (audio & visual)

Takeaways:

  • Documentation matters for future success (including code comments)
  • Team communication is crucial
  • Sometimes the solution is to start over
  • Not all project requirements are created equal
  • Projects change and evolve with time, so should the design
College of Engineering UtahStateUniversity

Blake Barber –Blake.Barber@usu.edu, Anya Nielson –A02072765@usu.edu, Garrett Freestone –A01972394@usu.edu, Zachary Hall –A022275881@usu.edu

Special Thanks to Quin Soderquist at Autoliv for mentoring us through this project.