说明：  In present time many cases of bike accident can be seen around us. peoples get injured or might be dead and one of the reason is not wearing helmet. Many peoples could save their life in accident cases if they weared helmet at the time of accident. Continuously road rules are violated. So as to overcome these problems, an Smart helmet is proposed having a control system built inside a helmet. Smart Helmet for Motorcyclist is a project undertaken to increase the rate of road safety among motorcyclists. The idea is obtained after knowing that the increasing number of fatal road accidents over the years is cause for concern among motorcyclists. It consist a RF transmitter and a RF receiver system. the bike will not get start without wearing helmet by the user, as user wear helmet a rf signal radiate transmitter and once these rf signal get sensed by the receiver placed in the ignition switch of the bike, bike will get start.