| 摘要 |
PROBLEM TO BE SOLVED: To provide an occupant detection system, capable of detecting existence of sitting of the occupant stably even when disturbances, such as water-pouring sheet of a vehicle, are present, and to provide a control method of the system. SOLUTION: The occupant detection system includes an electrode 75 provided in a vehicle seat for detecting the capacitance C<SB>1</SB>derived from a human body, an oscillator circuit 41 that supplies a reference signal S<SB>0</SB>containing sinusoidal waves to the electrode for detecting via a resistive element, a first comparator circuit 43 that binarizes the reference signal S<SB>0</SB>using a threshold corresponding to a given phase so as to produce a reference phase signal D<SB>0</SB>, a second comparator circuit 44 that detects the potential of the electrode for detecting as an electrode signal S<SB>1</SB>, and binarizes the electrode signal S<SB>1</SB>using a threshold corresponding to a phase that is substantially the same as a given phase of the reference signal S<SB>0</SB>so as to produce an electrode phase signal D<SB>1</SB>, and a control circuit 6 that measures delay times of the electrode phase signal D<SB>1</SB>relative to a rise timing and a down timing of the reference phase signal D<SB>0</SB>, so as to determine the presence of a seated occupant based on the delay times. COPYRIGHT: (C)2011,JPO&INPIT |
