Abstract: A method for updating a sensor offset and a medium encoded with a machine-readable computer program code for updating a sensor using a robust sensor learning algorithm wherein the method includes obtaining vehicle data signals, obtaining a position sensor data signal, the position sensor data signal being responsive to a stored positional offset data signal, determining whether algorithm initial conditions are satisfied, formulating a new positional offset data signal conditioned on satisfaction of the initial conditions, and storing said new positional offset data signal so as to combine said new positional offset data signal with said stored positional offset data signal and replace said stored positional offset data signal.

Abstract: A method for updating a sensor offset and a medium encoded with a machine-readable computer program code for updating a sensor using a robust sensor learning algorithm wherein the method includes obtaining vehicle data signals, obtaining a position sensor data signal, the position sensor data signal being responsive to a stored positional offset data signal, determining whether algorithm initial conditions are satisfied, formulating a new positional offset data signal conditioned on satisfaction of the initial conditions, and storing said new positional offset data signal so as to combine said new positional offset data signal with said stored positional offset data signal and replace said stored positional offset data signal.

Abstract: An exemplary embodiment of the invention is a method for controlling application of return torque in a vehicle power steering system. The method includes detecting a current hand wheel center and comparing the current hand wheel center to a previous hand wheel center. A change in hand wheel center is detected in response to the comparison. Application of return torque is controlled in response to detecting a change in hand wheel center.

Abstract: An electric motor actuator used in an environment of varying loads for varying time periods is efficiently designed to a predetermined specification in terms of both motor load and time and operated up to but not exceeding this specification over the full expected operating range. A motor load signal is low pass filtered with a plurality of time constants spanning a range of expected motor operation to generate a plurality of filtered motor load signals each associated with one of the time constants. Each of these filtered motor load signals is compared with a predetermined reference value corresponding to the associated time constant. If one or more of the filtered motor load signals exceeds the predetermined reference value with which it is compared, the one that so exceeds by the greatest margin is selected. A command current limit factor is derived from the selected filtered motor load signal and used to limit the commanded motor current.

Abstract: A vehicle power steering system has a steering shaft with a rotational position sensor providing signal rollover so that each sensor output indicates a plurality of potential absolute steering positions separated from each other by multiples of a rollover angle. Upon each initiation of vehicle operation, the system selects, as an unadjusted steering position, one of the plurality of absolute steering positions corresponding to an initial sensor output; and the system repeatedly updates the unadjusted steering position in response to sensor output changes, including sensed rollover events. The system repeatedly tests a set of revolution offsets with the updated unadjusted steering position and excludes any which indicate an out-of-range absolute steering position. The final remaining revolution offset is latched as the correct value.

Abstract: A vehicle power steering system has a steering shaft with a rotational position sensor providing signal rollover so that each sensor output indicates a plurality of potential absolute steering positions separated from each other by multiples of a rollover angle. Upon each initiation of vehicle operation, the system selects an absolute steering positions corresponding to an initial sensor output as an unadjusted steering position and repeatedly updates the unadjusted steering position in response to sensor output changes, including sensed rollover events. The system stores data dividing a two dimensional map of possible vehicle steering operating points defined by total steering torque and steering position into a first region of likely vehicle steering system operating points, a second region of unlikely steering system operating points indicating a revolution offset in a first direction, and a third region of unlikely steering system operating points indicating a revolution offset in an opposite direction.