Apparatus and method for stabilizing steering feel in motor-driven power steering
An apparatus for stabilizing a steering feel in a motor-driven power steering (MDPS) includes: an input unit configured to receive a column torque of a steering wheel; a calculation unit configured to convert the column torque signal inputted from the input unit into a target signal for generating a compensation signal of the steering wheel; and a compensation unit configured to calculate an assist torque for compensating for a main assist torque based on the target signal from the calculation unit.
1. An apparatus for a motor-driven power steering (MDPS), the apparatus comprising:
a main assist toque logic configured to provide a main assist torque signal based on a column torque signal indicative of torque applied to a steering wheel;
a compensation assist torque logic comprising a high-pass filter and configured to generate a compensation assist torque signal, wherein in the compensation assist torque logic, the column torque signal is applied to the high-pass filter to remove low frequency components in the column torque signal, wherein the compensation assist torque logic does not comprise a low-pass filter; and
a control logic configured to combine the main assist torque signal and the compensation assist torque signal for compensating the main assist torque signal to control a steering motor of the motor driven power steering.
2. The apparatus of claim 1 , wherein the compensation assist torque logic does not comprise a differentiator and is configured to generate the compensation assist torque signal without differentiating a signal therein.
3. The apparatus of claim 1 , wherein the compensation assist torque logic comprises a discretizer configured to discretize the column torque signal.
4. The apparatus of claim 3 , wherein the discretizer is configured to discretize the column torque signal based on a trapezoid rule.
5. The apparatus of claim 1 , wherein the compensation assist torque logic is configured to adjust a gain serving as an index of compensation degree.
6. A method of processing signals for a motor-driven power steering (MDPS), the method comprising:
providing a main assist torque signal based on a column torque signal indicative of column torque applied to of a steering wheel;
processing the column torque signal to provide a compensation assist torque signal in a compensation assist torque logic, in which the column torque signal is applied to a high-pass filter to remove low frequency components in the column torque signal, wherein processing the column torque signal does not involve applying a signal to a low-pass filter;
combining the main assist torque signal and the compensation assist torque signal for compensating the main assist torque signal to control a steering motor of the motor driven power steering.
7. The method of claim 6 , wherein processing the column torque signal does not involve differentiating a signal.
8. The method of claim 6 , wherein processing the column torque signal further comprises discretizing the column torque according to a trapezoid rule.
9. The method of claim 6 , wherein processing the column torque signal further comprises adjusting a gain serving as an index of compensation degree.