Abstract: In an electrical power steering apparatus, steering shaft reaction torque is estimated by a steering shaft reaction torque estimation unit, and a reference road reaction torque is estimated by a reference road reaction torque estimation unit. The estimated steering shaft reaction torque and the reference road reaction torque are weighted, and, in response, a target steering reaction torque is set by a target steering reaction torque generation unit, hysteresis width and slope of the target steering reaction torque are respectively adjusted, and steering feeling is thereby easily improved.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: A motor-driven power steering control apparatus assuring consistently comfortable steering operation of a motor vehicle includes a steering state detecting (10), a motor drive command value arithmetic device (20), a trouble detector (40), a motor drive command value corrector (51, 52) for decrementing a motor drive command value outputted from the motor drive command value corrector (51) from a predetermined initial value as a function of time lapse when a trouble detection signal is outputted from the trouble detector (40), and an element (30) for driving an assist motor in conformance with the output of the motor drive command value corrector (51, 52). The motor drive command value corrector (51, 52) includes a low-pass filter (515) for smoothing the motor drive command value. A value acquired through the low-pass filter (515) is employed as the predetermined initial value.

Abstract: A motor-driven power steering control apparatus assuring consistently comfortable steering operation of a motor vehicle includes a steering state detector (10), a motor drive command value arithmetic device (20), a trouble detector (40), a motor drive command value corrector (51, 52) for decrementing a motor drive command value outputted from the motor drive command value corrector (51) from a predetermined initial value as a function of time lapse when a trouble detection signal is outputted from the trouble detector (40), and an element (30) for driving an assist motor in conformance with the output of the motor drive command value corrector (51, 52). The motor drive command value corrector (51, 52) includes a low-pass filter (515) for smoothing the motor drive command value. A value acquired through the low-pass filter (515) is employed as the predetermined initial value.

Abstract: In an electrical power steering apparatus, steering shaft reaction torque is estimated by a steering shaft reaction torque estimation unit, and a reference road reaction torque is estimated by a reference road reaction torque estimation unit. The estimated steering shaft reaction torque and the reference road reaction torque are weighted, and in response, a target steering reaction torque is set by a target steering reaction torque generation unit, hysteresis width and slope of the target steering reaction torque are respectively adjusted, and steering feeling is thereby easily improved.

Abstract: A motor-driven power steering control apparatus assuring consistently comfortable steering operation of a motor vehicle includes a steering state detecting means (10), a motor drive command value arithmetic means (20), a trouble detecting means (40), a motor drive command value correcting means (51, 52) for decrementing a motor drive command value outputted from the motor drive command value correcting means (51) from a predetermined initial value as a function of time lapse when a trouble detection signal is outputted from the trouble detecting means (40), and a means (30) for driving an assist motor in conformance with the output of the motor drive command value correcting means (51, 52). The motor drive command value correcting means (51, 52) includes a low-pass filter (515) for smoothing the motor drive command value. A value acquired through the low-pass filter (515) is employed as the predetermined initial value.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: An electric power steering apparatus having a steering system capable of flexibly setting a relationship between a steering angle of a steering wheel and a wheel angle of a tire. The first motor controls steering reaction force exerted on the steering wheel. The on-center region determination section determines whether the steering wheel is in a position of an on-center region. The tire reaction force torque detection section detects tire reaction force torque transferred from the tire. The control section calculates a steering torque based on the tire reaction force torque and a torque gain. This torque is detected by the tire reaction force torque detection section. And the control section controls the first motor to exert the steering reaction force corresponding to the above calculated steering torque on the steering wheel. This control section also sets the torque gain in case of determining of on-center region larger than that in case of determining of non-on-center region.

Abstract: A motor-driven power steering control apparatus assuring consistently comfortable steering operation of a motor vehicle includes a steering state detecting means (10), a motor drive command value arithmetic means (20), a trouble detecting means (40), a motor drive command value correcting means (51, 52) for decrementing a motor drive command value outputted from the motor drive command value correcting means (51) from a predetermined initial value as a function of time lapse when a trouble detection signal is outputted from the trouble detecting means (40), and a means (30) for driving an assist motor in conformance with the output of the motor drive command value correcting means (51, 52). The motor drive command value correcting means (51, 52) includes a low-pass filter (515) for smoothing the motor drive command value. A value acquired through the low-pass filter (515) is employed as the predetermined initial value.

Abstract: A road surface reaction torque detector has a low-pass filter element whose time constant is determined in accordance with a vehicle speed that is detected by a vehicle steed detector and a motor rotation speed that is detected by a motor rotation speed detector. A road surface reaction torque estimation value is obtained in such a manner that the road surface reaction torque detector performs low-pass filter processing on steering shaft reaction torque signal that is outputted by a steering shaft reaction torque signal outputting means. As a result, an accuracy of estimation of road surface reaction torque is improved.

Abstract: A road surface reaction torque detector has a low-pass filter element whose time constant is determined in accordance with a vehicle speed that is detected by a vehicle steed detector and a motor rotation speed that is detected by a motor rotation speed detector. A road surface reaction torque estimation value is obtained in such a manner that the road surface reaction torque detector performs low-pass filter processing on steering shaft reaction torque signal that is outputted by a steering shaft reaction torque signal outputting means. As a result, an accuracy of estimation of road surface reaction torque is improved.

Abstract: An electric motor controller for a steering device that can apply an appropriate steering force to a steering wheel according to running conditions. An electric power steering controller of the present invention includes a steering shaft reaction force torque sensor for detecting a reaction force torque of a steering system, a superimposed reaction force torque calculating unit for multiplying a steering angle detected by the steering angle sensor by a gain to calculate a superimposed reaction force torque in the return direction of the steering wheel, and a control unit for controlling the gain so that the superimposed reaction force torque is reduced when a reaction force torque of the steering system is increased and the superimposed reaction force torque is increased when a reaction force torque of the steering system is decreased.