TAF PUBLISHING

The problem of exceeding the posted speed limit on roads typically leads to a high percentage of accidents and fatalities each year in most developed countries. Unless the vehicle's speed can be limited or controlled, drivers are able to drive at dangerously high speeds, risk lives, and attract costly speeding fines after being photographed by a ‘speed camera’. This may happen due to lack of awareness of the current speed limit in a particular area, or drivers not being careful enough to check their current vehicle speed. This paper describes a prototype system that can help reduce the over-speeding problem by fitting a transmitter on road signs and a receiver on vehicles. A maximum speed limit data signal is broadcasted continuously from a road sign, and a vehicle fitted with a wireless receiver module can detect the speed limit signal. The system can compare the vehicle's current speed with the speed limit and trigger an audible alarm (and alert message) to indicate that the speed limit has been exceeded. A working prototype has been designed, built and tested successfully using an 8-bit embedded microcontroller. Using appropriate transceiver modules, it is possible to implement Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) communications in order to implement a wide range of different and useful functions, including collision detection, vehicle identification and even the processing of fines for traffic rule violations. This paper describes the design details of an over-speeding warning system and addresses several other practical applications of wireless technologies for improving road safety. It is hoped that this research will encourage further research into V2V and V2I applications by demonstrating how low-cost wireless communications modules and low-cost microcontrollers can be used to perform several different useful functions. If products like the devices described in this paper are marketed and sold, they could save lives and promote safer driving by simply annoying or constantly warning drivers who exceed the current speed limit, using a loud audible alarm which cannot be disabled by the driver, and warning of nearby dangers.