Control unit for an electrical-motor-driven power steering apparatus
First Claim
1. A control unit for an electrical-motor-driven power steering apparatus, said control unit comprising:
- an assist current command value calculated based upon a steering torque of a steering wheel;
an assist current control value calculated based upon a motor current value of a motor and said assist current command value;
a motor for outputting an assist force based upon said assist current control value; and
an estimation means for estimating a reaction force on a road surface based upon at least one of said motor current value and said steering torque.
1 Assignment
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Accused Products
Abstract
In a control unit for an electrical-motor-driven power steering apparatus, there are provided an assist current command value calculated based upon a steering torque of a steering wheel, an assist current control value calculated based upon a motor current value of a motor and the assist current command value. A motor outputs an assist force based upon the assist current control value. Further, the control unit provides an estimation means for estimating a road surface μ based upon at least one of the motor current value and the steering torque. To the control unit, there are further inputted a vehicle speed obtained based upon rotation of a wheel, and a steering angle obtained based upon rotation of the steering wheel. Therefore, the estimation means estimates the road surface μ by comparing with a previously memorized standard value corresponding to the vehicle speed and the steering angle.
37 Citations
12 Claims
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1. A control unit for an electrical-motor-driven power steering apparatus, said control unit comprising:
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an assist current command value calculated based upon a steering torque of a steering wheel;
an assist current control value calculated based upon a motor current value of a motor and said assist current command value;
a motor for outputting an assist force based upon said assist current control value; and
an estimation means for estimating a reaction force on a road surface based upon at least one of said motor current value and said steering torque. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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Specification