The Audio Control Alert System (ACS) is an emergency siren detector for automobile use that is designed to control the media audio and alert occupants of approaching emergency vehicles for safety measures upon detection. Focusing on providing greater situational awareness when it matters most, the ACS alerts the driver to take prompt actions (yield, slow down, pull over, etc.) which are crucial to collision prevention. Implementation is based on utilizing a modern microprocessor to perform audio processing to filter specific sequence of tones and frequencies of surrounding sound. A perfect solution to be implemented onto the onboard computer of new generational automobiles equipped with ANC or as a standalone embedded system.

Accidents involving emergency vehicles such as fire trucks, ambulances, and police cars are a substantial problem in the United States. Vehicle fatality rates for emergency responders are estimated to be up to 4.8 times higher than the national average. Most emergency vehicle accidents occur at intersection. Because emergency vehicles are typically traveling at higher speeds in urgent situations, the accidents often result in severe injury or death to occupants of the emergency vehicle or the passenger vehicle involved.

Below are some statistics regarding emergency vehicle accidents illustrating how large the problem is in the U.S.

Ambulance Accidents in the U.S.

The National Highway Traffic Safety Administration (NHTSA) released a report in April of 2014 that provides an overview of the number of ambulance accidents in the United States. The agency studied the number of ambulance accidents over a 20 year period from 1992-2011.

Below are some of the key findings from the report:

Over the 20 year period, there were an estimated 4,500 accidents involving ambulances each year.
35% of accidents resulted in injury or fatality to at least 1 occupant of a vehicle involved.
An average of 29 fatal ambulance accidents produced 33 fatalities each year.
On average, 2,600 people are injured in 1,500 ambulance accidents each year.
Of those killed in an ambulance accident, 63% were occupants of a passenger vehicle, 21% were passengers in the ambulance, and 4% were the ambulance driver.

Firetruck Accidents in the U.S.

According to data from the NHTSA and the United States Fire Administration (USFA), firetruck accidents are the second leading cause of on-the-job deaths for firefighters.

Below are some key findings from an analysis of NHTSA data on firetruck accidents from 2000-2009:

Over that 10 year period, there were roughly 31,600 accidents involving fire vehicles.
Rollovers account for 66% of all fatal firetruck accidents.

Police Car Accidents in the U.S.

Using data from 1994-2002, researchers from the University of Washington performed an analysis of the number of fatalities each year that occur during police pursuits.

Below are some of their key findings:

Each year there are approximately 300 fatalities in the U.S. that occur during police pursuits.
Just over 30% of the fatalities occurred to people who were not involved in the pursuit.

Emergency responders perform an honorable and important job, but they still have a duty to respond to emergencies as safely as possible. Accidents involving emergency vehicles occur far too often in our country and many, if not most, of them are avoidable. Imagine if you or a love one got injured or killed in an accident with an ambulance, firetruck, police car, or other emergency vehicle that could have been prevented if such device was implemented to alert you ahead of time.

TBA

Prolific Circuits, specializes in embedded system designs and development. Our current project ACS, primary goal is to design an appropriate embedded solution for detecting approaching sirens to ensure driver safety and keeping the streets safer than ever for emergency vehicles when it matters most. Our engineers are experienced in all aspects of embedded system design. Our process of problem solving solution includes research, design, prototype, testing, through board design, to shipment of final product. Maintaining a well-linked team environment within our office allows us to prioritize several key elements we believe are representative of our quality as a business which include exceptional customer service and support as well as the establishment of easy-to-work-with professional partnerships.

http://prolificcircuits.com

The development of the ACS highlights the challenge of dealing with loud environment that generates a lot of noise which obscures the siren when analyzing signals. The noise can sometimes lead to false positives which make the siren detection partially reliable. It's relatively easy to get a signal and break it down into its component frequencies with the Fourier transform. However with weak signals or noisy environments, enhancements are necessary to interpret meaning of the output more accurately.

Reliable emergency siren detection will likely evolve in analyzing the audio and in removing sources of noise. Your support will help us further develop our product on many levels. Some ideas in considerations are:

Improve digital audio filtering to remove and enhance audio frequencies.
Enhance features such as voice prompt and alert display thru media system signalling the direction of siren and notifying driver to yield.
Run filters to remove higher frequency noise from the audio.
Upgrade microphone, RTOS, increase FFT Size for better resolution.
Apply other technique/method such as Doppler Effect for approaching / departing vehicles, etc.