Fault detection for steering control for a vehicle

摘要

A steering system and method are described for a vehicle having steerable wheels, with steering of the wheels controlled, at least in part, by a valve assembly. A ground speed of the vehicle may be determined. Whether a steering command is being provided to a valve assembly may also be determined. An operational pressure at the valve assembly may be determined with a pressure sensor. A threshold pressure may be determined based upon the ground speed and/or whether a steering command is currently being provided. The operational pressure may then be compared with the operational pressure, and steering control with the valve assembly disabled based upon the comparison.

主权项

1. A steering method for an agricultural vehicle having one or more steerable wheels, a hydraulic steering device coupled to at least one of the one or more steerable wheels, a valve assembly configured to hydraulically control the hydraulic steering device in order to steer at least one of the one or more steerable wheels, a controller configured to provide steering commands to the valve assembly to cause the valve assembly to hydraulically control the hydraulic steering device, and a pressure sensor in hydraulic communication with the valve assembly, the steering method comprising:
determining a ground speed of the agricultural vehicle; determining whether the controller is currently providing a steering command to the valve assembly; determining an operational pressure at the valve assembly with the pressure sensor; determining a threshold pressure based upon, at least in part, one or more of the ground speed of the agricultural vehicle and whether the controller is currently providing a steering command to the valve assembly; comparing the operational pressure with the threshold pressure; and disabling the control of the hydraulic steering device by the valve assembly based upon, at least in part, the comparing of the operational pressure with the threshold pressure; wherein the controller is determined to be currently providing a first steering command to the valve assembly, the method further comprising: determining an initial pressure at the valve assembly with the pressure sensor for a time prior to execution of the first steering command by the valve assembly; wherein the threshold pressure is determined to be equal to the initial pressure plus a pressure offset; and wherein the control of the hydraulic steering device by the valve assembly is disabled based upon, at least in part, determining that the threshold pressure exceeds the operational pressure.