US 12,188,530 B1
Hydraulic motion detection via solenoid electronic feedback
William R Mayhew, Ann Arbor, MI (US); Steven B Christ, Ann Arbor, MI (US); and Niranjan Das, Ann Arbor, MI (US)
Assigned to FCA US LLC, Auburn Hills, MI (US)
Filed by FCA US LLC, Auburn Hills, MI (US)
Filed on Oct. 12, 2023, as Appl. No. 18/485,720.
Int. Cl. F16D 48/06 (2006.01); F16H 61/02 (2006.01)
CPC F16D 48/066 (2013.01) [F16H 61/0251 (2013.01); F16D 2500/3028 (2013.01); F16D 2500/5012 (2013.01); F16D 2500/7041 (2013.01); F16D 2500/7109 (2013.01); F16H 2061/0255 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A hydraulic piston position determination system for a vehicle, the hydraulic piston position determination system comprising:
a hydraulic piston actuator configured to move a piston member in response to a hydraulic fluid pressure to engage/disengage a friction member of the vehicle;
a hydraulic solenoid valve configured to control the hydraulic fluid pressure at the hydraulic piston actuator by regulating a flow of hydraulic fluid from a hydraulic fluid supply system; and
a controller configured to:
control the hydraulic piston actuator by controlling the hydraulic solenoid valve according to an actual duty cycle based on a flow demand change associated with the hydraulic piston actuator; and
determine a position of the hydraulic piston actuator based on (i) a magnetic reluctance change and (ii) a difference between the actual duty cycle and a steady-state duty cycle for the hydraulic solenoid valve.