Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Denki K.k.

Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Oval Engineering Co., Ltd.

Suzuki Motor Corporation

Mitsubushi Denki Kabushiki Kaisha

Shunichi Wada

Kazuhisa Nishino

Takayuki Kifuku

Shozo Takizawa

Shigeki Ohtagaki

Hirohisa Awa

Tadao Tanaka

Noriyuki Inoue

Mitsuhiko Harara

Masahiko Kurishige

Minoru Tatemoto

Yasuo Naito

Yuji Takatsuka

Masanori Takagi

Ryoji Nishiyama

Shinichi Kohge

Yasutaka Taniguchi

Mitsunori Maruyama

Yoshihiro Tsuda

Masayuki Yano

Setsuhiro Shimomura

Yoshiaki Asayama

Naotake Kumagai

Kazumichi Tsutsumi

Yoshihiko Utsui

Munenori Yamamoto

Yasuo Naitou

Masami Kabuto

Masahiro Tado

Teruki Fukami

Kuniteru Okuda

Tetsuya Terada

Kouji Mitsuhata

Wataru Fukui

Hiroshi Nishimura

Masahiro Yokotani

Naoki Hiraoka

Toshihide Satake

Tadayuki Hara

Takahiro Okanoue

Hidehiko Sugimoto

Hiroshi Satoh

Yasuaki Hata

Kenji Hayase

Hiroyuki Takada

Yasushi Sasaki

Mitsuhiko Hara

Kazuhisa Nisino

Masaya Ushio

Shunzou Oshima

Hisasi Inoyama

Yuji Mitsubishi Electric Takatsuka

A method of controlling an automotive electric power steering system includes estimating a first road reaction torque from driver's steering torque detected by a steering torque detector. A second road reaction torque is estimated from the steering angle detected by a steering angle sensor. A returning torque compensator calculates a steering wheel-assisting torque from the second road reaction torque. An assisting torque is generated by an electric motor according to the result of the calculation, and is controlled in a direction to return the steering wheel to its center position. The returning torque compensator determines whether the steering angle sensor is faulty when the difference between the first and second road reaction torques is greater than a given value.

Electric power steering controller and method of controlling same

A power steering control system is provided with a road surface reaction torque detector in which a motor inertia torque is subtracted from a value obtained by adding steering torque and motor torque, and the value is passed through two stages of primary filters to obtain a road surface reaction torque. In such a computation, the inertia term of the steering wheel manipulation force does not depend on frequency and high frequency components do not bring about any unusually large steering wheel return force. Therefore, a driver can drive without difficulty in adapting to the power steering.

Electric power steering control system and method for controlling electric power steering control system

An electric power steering controller including a motor for generating torque for assisting the steering torque of a driver to assist the steering force of a steering system. The controller includes a road reaction torque detector for detecting road reaction torque received by tires from the surface of a road, and a road detection torque addition control for controlling the torque of the motor based on the road reaction torque. The electric power steering controller enables the steering wheel to be returned to its starting point without adding torque in a direction in which the driver returns the steering wheel when the driver contgrols the steering wheel with the small road reaction torque of the tires, for example, when turning at an intersection at a low speed or when turning at a gently curved portion of a road at a high speed.

Electric power steering controller and control method thereof

An electric power steering controller and a control method for assisting a driver during handling a steering wheel in a condition of a small road surface reaction torque of a tire by generating an auxiliary return torque for letting the steering wheel return to its original position. A first road surface reaction torque is estimated from a steering torque of a driver detected by a steering torque detector, a motor acceleration detected by a motor acceleration detector, and a motor current detected by a motor current detector. A second road surface reaction torque is estimated from a steering angle detected by a steering angle sensor, and a vehicle speed detected by a vehicle speed detector. Then, first and second auxiliary return torque signals of the steering wheel are computed from a road surface reaction torque, and, based on the computed result, a torque of the motor is controlled in direction so the steering wheel is returned to its original position.

Electric power steering controller and control method

A motor-driven power steering apparatus comprises: a torque sensor for detecting a steering torque; an assist indicator for outputting an indication signal which indicates the direction and magnitude of an output torque of a motor power-assisting a steering mechanism; a dither signal generator for outputting a high-frequency dither signal; and a control circuit for controlling a current supplied to the motor according to the indication signal provided by the assist indicator and the dither signal provided by the dither signal generator.

Motor-driven power steering apparatus

To estimate the rotation speed of the motor for assisting a steering torque regardless of the running state of a vehicle with accuracy, an application voltage estimation value obtained by subtracting a correction voltage obtained based on a detection current value detected by current detection means from the inter-terminal voltage measurement value of the motor is output and the rotation speed of the motor is estimated based on this application voltage estimation value and the detection current value.

Electric power steering controller

A DC motor driven power steering system for a motor vehicle includes a motor current detection circuit for detecting a motor current flowing through the DC motor, a power supply voltage detection circuit for detecting a power supply voltage applied to the bridge commutation circuit, a motor voltage estimating unit for estimating a voltage applied across the DC motor on the basis of the power supply voltage applied to the bridge commutation circuit and the pulse-width modulated control signals used for controlling the bridge commutation circuit, and a motor rotation detecting means for detecting the rotation state of the DC motor on the basis of the motor current and the estimated motor voltage applied to the DC motor. High reliability can be ensured for detection of the rotation state of the DC motor.

DC motor driven power steering system for a motor vehicle

A load short-circuit failure detection apparatus comprises load current drive means 8, load current control means 7, load current detection means 6 and load short-circuit failure judging means 9 and judges that a short-circuit failure occurs in a load when a state in which a load current detection value exceeds a predetermined value within a first predetermined time continues for a second predetermined time so that the load drive means can be protected, a short-circuit failure of the load can be detected, and the erroneous detection of a short-circuit failure caused by a transient overcurrent can be prevented.

Load short-circuit failure detection method and apparatus and electric

Controller for motor-driven power steering

A motor-driven power steering system for a motor vehicle implemented inexpensively in a simplified structure allows operation of a steering assist torque generating motor even in the vicinity of a neutral point while preventing rotation of the motor in a direction reverse to the steering direction as well as self-rotation of a steering wheel notwithstanding of occurrence of abnormality in a controller implemented by a CPU. The motor-driven power steering system includes a CPU (3) for controlling a motor (2) in dependence on output of a steering torque detecting unit (1), an interlock means (5) for limiting driving operation of the motor (2) upon occurrence of abnormality in the CPU (3), and a motor driving means (6) for driving the motor (2) in accordance with commands issued by the CPU (3).

Motor-driven power steering system for motor vehicle

A power steering control apparatus for a motor vehicle which ensures an appropriate steering force conforming to the prevailing road condition and hence the safety for the motor vehicle even when the wheels are locked due to hard brake applied on a slippery road. The apparatus includes a first microcomputer for determining a driving torque of a steering assist motor on the basis of steering torque information generated upon steering of a steering wheel and pseudo vehicle speed information to thereby generate and output a driving signal for the steering assist motor on the basis of the driving torque, and a second microcomputer for generating the pseudo vehicle speed signal on the basis of wheel rotation speed signals and acceleration/deceleration signal of the motor vehicle to thereby generate and output a brake actuation signal for wheels of the motor vehicle on the basis of the pseudo vehicle speed signal, the acceleration/deceleration information and brake application information. The first microcomputer may further include a memory for storing steering assist characteristics according to which the torque of the assist motor is changed.

Power steering control apparatus for motor vehicle

A vehicle control apparatus includes a steering torque sensor (1) for sensing a steering torque, a motor (3) for generating a steering assisting force, a CPU (22) for determining a motor drive direction based on at least the steering force and a motor drive direction restricting circuit (25) for restricting the drive direction of the motor (3) determined by the CPU (22) based on a steering force determination level as a motor drive direction determination criterion and the steering force, and the steering force determination level is changeable. With this arrangement, there is provided the vehicle control apparatus with safety and reliability by which the motor can be controlled with redundancy, the steering force determination level does not require such accuracy as to use pinpoint accuracy and further even if an abnormal state is caused in a motor output when a steering wheel is released from a hand and a steering torque exceeding the steering force determination level is generated, the steering force determination level is instantly changed to thereby restrict a motor drive direction so that the self-turn of the steering wheel is prevented.

Vehicle control apparatus

A control apparatus for a motor-driven power steering system of a motor vehicle controls the steering system such that a steering torque required to be applied by a driver is prevented from increasing abruptly or steeply even when generation of an assist torque applied to the steering system for assisting the driver in steering operation is to be stopped. The control apparatus includes an operation stop decision mechanism (111, 112, OR) for deciding whether or not an operation stop command is to be issued for stopping control operation for the motor-driven power steering system, a torque detecting mechanism (16, 113) for detecting a steering torque transmitted from an input shaft (21a) to an output shaft (21c) of a steering column (21) of the motor-driven power steering system, and an assist torque control mechanism (114, 116, 117, 118, 13) for updating an assist torque applied by an electric motor (20) to the output shaft (21c) with an assist torque control quantity determined on the basis of a detected torque value outputted from the torque detection mechanism (16, 113), wherein upon issuance of the operation stop command by the operation stop decision mechanism (111, 112, OR), the assist torque control mechanism stops application of the assist torque, provided that the detected torque value is lower than a predetermined value inclusive thereof.

Control apparatus for motor-driven power steering system of motor vehicle

An electric power steering control apparatus is intended to improve the convergence and control stability of a returning motion of a steering wheel when a driver of a vehicle on which the apparatus is installed lets his or her hands free from the steering wheel, and to reduce a burden to the driver when an excessive steering torque occurs during the returning motion. The apparatus includes a steering torque sensor 8 for detecting a steering torque of a steering system of the vehicle, a motor rotational-speed detector 7 for detecting a rotational speed of the electric motor, and a rotational-speed controller for controlling the electric motor based on output signals from the steering torque sensor and the motor rotational-speed sensor so that when the steering torque as detected is less than a predetermined torque value, the rotational speed of the electric motor does not exceed a predetermined speed value corresponding to the predetermined torque value.

Electric power steering control apparatus

Growing community of inventors

Himeji, Japan

Shunichi Wada