Patent ID: 8676447

Claim:
An occupant posture sensing apparatus, comprising: a capacitance sensor disposed to a vehicle interior ceiling of a vehicle and sensing capacitance between a head of a human body sitting on a seat and the vehicle interior ceiling, wherein the capacitance sensor comprises two sensing electrodes which are arranged at portions of the vehicle interior ceiling that are above the seat so as to be capable of sensing capacitances between the head of the human body sitting on the seat and the vehicle interior ceiling, and which sense capacitances between the head of the human body sitting on the seat and the vehicle interior ceiling; a detecting circuit which is connected to each of the sensing electrodes and detects a position of the head of the human body based on sensing signals from the sensing electrodes, wherein the detecting circuit comprises a capacitance sensing circuit sensing a capacitance value based on the sensing signals from the sensing electrodes; and a posture determining circuit which determines a sitting posture of the human body according to a detection result from the detecting circuit.