Vehicle seat position sensing

• Main Authors: Michael K Rao, Jialiang Le, Saeed David Barbat
• Format: Patent
• Language: English
• Published: 06.09.2017
• Subjects: MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PERFORMING OPERATIONS; PHYSICS; SEATS SPECIALLY ADAPTED FOR VEHICLES; TESTING; TRANSPORTING; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDEDFOR; VEHICLES IN GENERAL

A vehicle system 125 includes a sensor 135 programmed to measure angular displacement of a rotatable seat (105, figure 1) comprising a seat portion 110, relative to a base 120. Angular displacement is measured based on orientation of a magnetic field generated by a magnet 130. The sensor 135 may include resistors (R1-R4, figure 5) arranged in a Wheatstone bridge. Alternatively, angular displacement is measured based on magnetic field generated by a magnet 130 relative to a rotating circle gear (145, figure 6) comprising teeth (150) and gaps (155). The magnetic field may increase in strength when a tooth (150) passes near the magnet 130 and decrease when a gap (155) passes near the magnet. Alternatively, angular displacement is measured based on light generated by a light emitting device (165, figure 7) relative to circle gear (145), wherein rotation of gear teeth may periodically block light, and gaps may periodically allow light to pass to a receiver (170, figure 8). A restraint control module (210, figure 9) may receive seat position sensor signals. A processor 140 may process a collision signal and selectively deploy restraint devices (250, e.g. driver or curtain airbag) based on angular displacement of seat 105.