Abstract: An occupant presence sensor apparatus disposed in a seat includes first and second substantially non-compliant force translation plates generally parallel to the seating surface of the seat, an elastomeric mat disposed between the first and second force translation plates, and a switch mechanism disposed between the first and second force translation plates within an opening formed in the elastomeric mat. The elastomeric mat includes a distributed array of hollow protuberances that extend toward and contact the force translation plates, and the mat has a stiffness that normally provides a clearance between the switch mechanism and one of the force translation plates. When an occupant of specified or higher weight sits on the seating surface, the protuberances collapse and the force translation plates activate the switch mechanism.

Abstract: An occupant presence sensor apparatus disposed in a seat includes first and second substantially non-compliant force translation plates generally parallel to the seating surface of the seat, an elastomeric mat disposed between the first and second force translation plates, and a switch mechanism disposed between the first and second force translation plates within an opening formed in the elastomeric mat. The elastomeric mat includes a distributed array of hollow protuberances that extend toward and contact the force translation plates, and the mat has a stiffness that normally provides a clearance between the switch mechanism and one of the force translation plates. When an occupant of specified or higher weight sits on the seating surface, the protuberances collapse and the force translation plates activate the switch mechanism.