Safety Enhancement Features for 21 st Century Automobile Don VanderLaan Jeremy Konz Natalie Hannon Tom Aprik Sponsor: General Motors

 Purpose  Design Parameters  Hardware  Algorithms  Proof of Concept Presentation Outline

Purpose  Increase automobile safety and driver awareness with an “alerting system”  Detect an emergency siren audio signal  Turn down the volume of the car stereo  Display an indicator symbol on the dashboard

Background  Increase safety in conjunction with the Emergency Vehicle Safety Initiative, a partnership between the U.S. Fire Administration (USFA) and the Society of Automotive Engineers (SAE).

Design Objectives  Develop Matlab code for signal processing  Program microcontroller with signal processing code  Interface components to build prototype  Test prototype for reliability  Package prototype for automobile

Hardware  Main processing is done in dsPIC unit  dsPIC is combination DSP/µC by Microchip –Eliminates need for separate DSP and µC  Specialized DSP algorithm libraries for convolution  Code written in C

 External EEPROM is needed to store microphone waveform data in combination with original siren waveform  Specialized microphone could be fitted, our project will be generic  Radio speaker control relay  LED, would be CAN message to instrument cluster in real car Hardware ctd.

Siren Detection Algorithm Siren will be detected using a matched filter Siren will be detected using a matched filter Equivalent to convolution without the time reversal Equivalent to convolution without the time reversal Threshold the output to determine if the siren is present Threshold the output to determine if the siren is present Must be robust enough to work under 10% Doppler shift Must be robust enough to work under 10% Doppler shift

Proof of Concept  Tested with a SNR of 0.27 – far below practical conditions  Convolved output clearly indicates a siren present

Proof of Concept ctd.  Tested with SNR of 0.27 and a Doppler shift of 10%  Convolved output still indicates siren present

Conclusion  Questions?  Next Steps