Steering system monitoring
AssigneeVolvo Car Corporation
InventorsAnders Hansson, Carl-Johan Häll
Life of this patent
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Abstract
The disclosure relates to a method including the steps of: acquiring a time sequence of sets of vehicle parameter values; determining, for each set of acquired vehicle parameter values, based the set of acquired vehicle parameter values, a measure indicative of an observed strain in a steering rod, between a steering actuator and a wheel; determining, for each set of acquired vehicle parameter values, a measure indicative of a predicted strain in the rod, between the steering actuator and the wheel; and determining the functional status of the steering system based on a relation between the measures indicative of the observed strain in the rod and the measures indicative of the predicted strain in the rod.
Claims16
A method of determining a functional status of a steering system of a vehicle, the method comprising:
- acquiring a time sequence of sets of vehicle parameter values, each set of vehicle parameter values including a first parameter value indicative of a desired change in a direction of travel of the vehicle, a second parameter value indicative of a vehicle speed, and a third parameter value indicative of an actuation force currently applied by a steering actuator of the steering system to a rod of the steering system;
- determining, for each set of acquired vehicle parameter values, based on the first parameter value, the second parameter value and the third parameter value, a measure indicative of an observed strain in a portion of the rod positioned between the steering actuator and a wheel of the vehicle, as a time sequence of measures indicative of observed strain in the rod;
- determining, for each set of acquired vehicle parameter values, based on the first parameter value and the second parameter value in the set of acquired parameter values, and a set of previously determined measurement values indicative of strain values for different values of the first parameter and the second parameter, a measure indicative of a predicted strain in the portion of the rod positioned between the steering actuator and the wheel, as a time sequence of measures indicative of predicted strain in the rod;
- and
- determining the functional status of the steering system based on a relation between the time sequence of measures indicative of the observed strain in the rod and the time sequence of measures indicative of the predicted strain in the rod.
A steering system monitoring unit implemented in processing circuitry, for monitoring a functional status of a steering system including a rod coupled to a wheel and being arranged to turn the wheel under the control of a steering actuator operable to apply an actuation force to the rod, the steering system monitoring unit being configured to:
- acquire a time sequence of sets of vehicle parameter values, each set of vehicle parameter values including a first parameter value indicative of a desired change in a direction of travel of the vehicle, a second parameter value indicative of a vehicle speed, and a third parameter value indicative of the actuation force currently applied by the steering actuator to the rod;
- determine, for each set of acquired vehicle parameter values, based on first parameter value, the second parameter value and the third parameter value, a measure indicative of an observed strain in a portion of the rod positioned between the steering actuator and the wheel, as a time sequence of measures indicative of observed strain in the rod;
- determine, for each set of acquired vehicle parameter values, based on the first parameter value and the second parameter value in the set of acquired parameter values, and a set of previously determined measurement values indicative of strain values for different values of the first parameter and the second parameter, a measure indicative of a predicted strain in the portion of the rod positioned between the steering actuator and the wheel, as a time sequence of measures indicative of predicted strain in the rod;
- and
- determine the functional status of the steering system based on a relation between the time sequence of measures indicative of the observed strain in the rod and the time sequence of measures indicative of the predicted strain in the rod.
A vehicle having a steering system including a wheel, and a rod coupled to the wheel and arranged to turn the wheel under the control of a steering actuator operable to apply an actuation force to the rod a steerable wheel;
- and a steering system monitoring unit configured to:
- acquire a time sequence of sets of vehicle parameter values, each set of vehicle parameter values including a first parameter value indicative of a desired change in a direction of travel of the vehicle, a second parameter value indicative of a vehicle speed, and a third parameter value indicative of the actuation force currently applied by the steering actuator to the rod;
- determine, for each set of acquired vehicle parameter values, based on first parameter value, the second parameter value and the third parameter value, a measure indicative of an observed strain in a portion of the rod positioned between the steering actuator and the wheel, as a time sequence of measures indicative of observed strain in the rod;
- determine, for each set of acquired vehicle parameter values, based on the first parameter value and the second parameter value in the set of acquired parameter values, and a set of previously determined measurement values indicative of strain values for different values of the first parameter and the second parameter, a measure indicative of a predicted strain in the portion of the rod positioned between the steering actuator and the wheel, as a time sequence of measures indicative of the predicted strain in the rod;
- and
- determine the functional status of the steering system based on a relation between the time sequence of measures indicative of the observed strain in the rod and the time sequence of measures indicative of the predicted strain in the rod.
Dependencies are inferred from the claim text.