Abstract: An airbag apparatus for a motorcycle includes an airbag module with an airbag that is capable of being inflated and deployed so as to restrain the rider on a seat disposed behind the fuel tank from the front that is mounted on the vehicle body frame. Without requiring a modification of the configuration of the appearance constituting parts of the motorcycle, water, mud, or the like is prevented from breaking into the airbag module. The front portion of the seat that covers the airbag module to be mounted on the vehicle body frame at a position rearwardly of the fuel tank from above and extends to the position on the rear portion of the fuel tank is constructed so as to be opened with the rear side raised upwardly in response to inflation and deployment of the airbag.

Abstract: A passenger detecting system includes a plurality of antenna electrodes provided in a seat, a signal generating section, a detecting section, a switching circuit and a control unit. The signal generating section generates an electrode signal. The switching circuit sequentially supplies the electrode signal to the plurality of antenna electrodes one by one in response to a switching control signal. The detecting section detects change of the electrode signal to generate a detection signal when the electrode signal is supplied to each of the plurality of antenna electrodes. The control unit outputs the switching control signal to the switching circuit and generates a passenger data associated with a passenger on the seat based on the detection signal for each of the plurality of antenna electrodes.