To reduce the speed of the fast moving vehicles automatically, speed
breakers are used with Witricity technique. A power line is laid under the road with a series of coils of a certain frequency, at places where the speed of the vehicle has to be reduced. Every vehicle has a coil in it which has the same resonant frequency as the underground coil. Whenever a vehicle approaches the speed breaker, the magnetic
field produced from the underground coil makes the coil in the vehicle to resonate with the same frequency. Due to this current gets induced in the coil of the vehicle. The current which gets induced is then sent to a current comparator where it is compared with a reference current and now the error signal produced is applied to the speed
limiter of the vehicle which now reduces the speed of the vehicle according to a pre-programmed mechanism.

The power line is laid under the road with a series of resonating coils given below depicts the concept of Witric speed breaking system.Wireless power technology offers the promise of cutting the last cord, allowing users to seamlessly recharge mobile devices as easily as data are transmitted through the air. Initial work on the use of magnetically coupled resonators for this purpose has shown promising results. We present new analysis that yields critical insight into the design of practical systems, including the introduction of key figures of merit that can be used to compare systems with vastly different geometries and operating conditions. A circuit model is presented along with a derivation of key system concepts, such as frequency splitting, the maximum operating distance (critical coupling)[10]and the behavior of the system as it becomes under coupled. This theoretical model is validated against measured data and shows an excellent average coefficient of determination of 0.9875. An adaptive frequency tuning technique is demonstrated, which compensates for efficiency variations encountered when the transmitter-to-receiver distance and/or orientation are varied. The orientation within the range of the transmitter and still achieve a near-constant efficiency of over 70% for a range of 0-70 cm similar type of coils is connected to the vehicle for the speed breaking purpose.

Witric speed breakers are more reliable, efficient, fast operating, automatic compared to the ordinary speed breakers accidents and it is harmless to humans. Additional laying of wires for this technique is not needed since the power for lighting the street lamps can be used. There is less maintenance cost. The coils can be tuned to any frequency since various speeds can be controlled. It does not require any human intervention for the speed control . This concept offers greater possibilities for controlling the speed of the vehicle and it can be utilized wherever you want it, “when you want it in real time”.