A system for detecting hands-on or off of a steering wheel and a method thereof, include a direct sensor configured for detecting a hands-on sense value depending on a grip area of the steering wheel; an indirect sensor configured for detecting a hands-on sense value depending on a magnitude of a torque for rotating the steering wheel; and a controller connected to the first sensor and the second sensor and combining a direct hands-on sense value detected by the direct sensor and an indirect hands-on sense value detected by the indirect sensor to each other to determine a grip state of the steering wheel depending on a combined hands-on sense condition, and then to display and warn a result of determining the grip state of the steering wheel through an output unit.

A steering feedback unit detects a steering torque generated according to an operation of a steering wheel, a road-wheel steering unit connected to the steering feedback unit to allow a steering of a wheel to be performed according to a steering angle or the steering torque transmitted from the steering feedback unit, and a control unit determines the steering torque detected in the steering feedback unit as a steering angle selectively according to a preset standard vehicle speed and standard steering speed to transmit the determined steering angle to the road-wheel steering unit, and controls the steering of the wheel according to the steering angle to be performed, or transmits the steering torque detected in the steering feedback unit to the road-wheel steering unit and control the amount of motor torque for the steering of the wheel to be determined.

A steering feedback unit detects a steering torque generated according to an operation of a steering wheel, a road-wheel steering unit connected to the steering feedback unit to allow a steering of a wheel to be performed according to a steering angle or the steering torque transmitted from the steering feedback unit, and a control unit determines the steering torque detected in the steering feedback unit as a steering angle selectively according to a preset standard vehicle speed and standard steering speed to transmit the determined steering angle to the road-wheel steering unit, and controls the steering of the wheel according to the steering angle to be performed, or transmits the steering torque detected in the steering feedback unit to the road-wheel steering unit and control the amount of motor torque for the steering of the wheel to be determined.

[Problem] An object of the present invention is to provide an electric power steering apparatus capable of smoothly switching the control systems without self-steer by gradually changing a control torque of the torque control and a command value of the position/speed control upon fade processing that switches the control systems.

[Means for Solving the Problem] The present invention is the electric power steering apparatus including a torque sensor to detect a steering torque and a motor control unit to control a motor that applies an assist torque to a steering system of a vehicle, comprising: a function to switch a control system of the motor between a torque control system of a torque system to control a motor output torque and a position/speed control system of a steering angle system to control a steering angle of a steering in accordance with a predetermined switching trigger, wherein each of a steering angle command value and a steering angle speed of the position/speed control system and an assist torque level of the torque control system gradually change sensitive to the steering torque, when shifting from the torque control system to the position/speed control system or vice versa.

[Problem] An object of the present invention is to provide an electric power steering apparatus capable of smoothly switching the control systems without self-steer by gradually changing a control torque of the torque control and a command value of the position/speed control upon fade processing that switches the control systems.

[Means for Solving the Problem] The present invention is the electric power steering apparatus including a torque sensor to detect a steering torque and a motor control unit to control a motor that applies an assist torque to a steering system of a vehicle, comprising: a function to switch a control system of the motor between a torque control system of a torque system to control a motor output torque and a position/speed control system of a steering angle system to control a steering angle of a steering in accordance with a predetermined switching trigger, wherein each of a steering angle command value and a steering angle speed of the position/speed control system and an assist torque level of the torque control system gradually change sensitive to the steering torque, when shifting from the torque control system to the position/speed control system or vice versa.

An electric power steering apparatus includes a control section that includes a feed-back control section which sets a viscoelastic model as a reference model within a predetermined angle at front of a rack end. The feed-back control section includes a feed-back element to calculate a target rack displacement based on an input-side rack axial force and a control element to output an output-side rack axial force based on a position deviation between the target rack displacement and a rack displacement.

An electric power steering apparatus includes a control section that includes a feed-back control section which sets a viscoelastic model as a reference model within a predetermined angle at front of a rack end. The feed-back control section includes a feed-back element to calculate a target rack displacement based on an input-side rack axial force and a control element to output an output-side rack axial force based on a position deviation between the target rack displacement and a rack displacement.

Technical features of a steering system include a control module that dynamically determines an operating mode based on a set of input signal values such as lateral acceleration signal values and corresponding handwheel position values. The control module dynamically determines and learns classification boundaries between multiple operating modes based the input signal values. The control module further calibrates the steering system according to operating mode that is determined using the classification boundaries.

Technical features of a steering system include a control module that dynamically determines an operating mode based on a set of input signal values such as lateral acceleration signal values and corresponding handwheel position values. The control module dynamically determines and learns classification boundaries between multiple operating modes based the input signal values. The control module further calibrates the steering system according to operating mode that is determined using the classification boundaries.

A control system calculates inputs to a control target that has m inputs and n outputs (m=n, each of m and n is a natural number that is more than one), while designating a plurality of combinations of the inputs and the outputs. A feedback controller calculates, with respect to each designated combination, a control input to a non-interference controller based on a difference between a target value and a current value of the control quantity to make the current value follow the target value. The non-interference controller executes, with respect to each designated combination, a non-interference control to reduce influence due to mutual interference between n control quantities. This reduces the number of combinations of the inputs and the outputs, the combinations whose mutual interference needs considering; thereby, the non-interference control may be easily achieved.