Abstract: To provide an electric power steering apparatus capable of constructing a microcomputer redundant system that controls the motor with an extremely small amount of calculation and improving the reliability of the apparatus.

Abstract: In an electric power steering control system, a road surface reaction torque estimator estimates a road surface reaction torque on the basis of steering wheel angle. A neutral point learning unit and a neutral point compensator learn a neutral point of the steering wheel on the basis of the road surface reaction torque with respect to the steering wheel angle. A return torque for returning the steering wheel to the neutral point is computed from a difference between a current angle of the motor and the learned neutral point. As a result, the steering wheel returns to the neutral point under the current driving condition without application of any force to the steering wheel by the driver.

Abstract: There is provided an electric motor controller for a steering device that can give an appropriate steering force to a steering wheel according to running conditions. An electric power steering controller of the present invention is provided with 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 a steering wheel and a control unit for controlling the gain such that the superimposed reaction force torque is reduced when a reaction force torque of the steering system is large and the superimposed reaction force torque is increased when a reaction force torque of the steering system is small.

Abstract: In the conventional electric power steering control system, a steering force applied by a driver to a steering wheel is detected and a torque of a motor is determined on the basis of the detected steering force. In such a prior system, at the time of going round a gentle curve, going round an intersection at an extremely low speed or the like, any steering wheel return torque is not generated unless the driver returns the steering wheel, and drive feeling is not improved. First, a road surface reaction torque estimator 15 estimates a road surface reaction torque on the basis of a steering wheel angle. A neutral point learning unit 24 and a neutral point compensator 25 learn a neutral point of the steering wheel on the basis of the road surface reaction torque with respect to the steering wheel angle. A return torque for returning the steering wheel to the neutral point is computed from a difference between a current angle of the motor and the learned neutral point.

Abstract: 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.

Abstract: A camera and a beam-scan type laser radar whose optical axes are coincident are mounted on a vehicle. A lane detector detects the vehicle's own lane on a display image by processing an image picked up by the camera. A coordinate transforming device transforms the coordinates of positional information of an object, most likely a vehicle, detected by the laser radar in conformity with coordinates on the image of the camera. Another detector compares a position of the vehicle's own lane with a position of the detected object, judges whether or not the detected object is within the vehicle's own lane, and separates the detected object within the vehicle's own lane from objects detected outside the vehicle's own lane. A failure detection method and a corresponding apparatus are provided to determine whether the optical axes of the camera and the laser radar are coincident.

Abstract: An apparatus for determining acceleration of a motor vehicle includes an acceleration sensor for generating a signal representing acceleration of the motor vehicle, wheel speed sensor means for generating wheel speed signals indicating wheel speeds of individual wheels of the motor vehicle, and a first arithmetic unit for determining a mean value of the output signal of the acceleration sensor over a predetermined period in the running state of the motor vehicle in which the motor vehicle is making a substantially straight drive at a substantially constant speed on a substantially level ground surface during the aforementioned predetermined period, to thereby output a signal indicating the mean value, and a second arithmetic unit for determining acceleration of the motor vehicle by subtracting the mean value from the output of the acceleration sensor.

Abstract: A unified control device for a vehicle including an anti-skid braking system and power steering control system is controlled by two microcomputers (4B and 24B). On the basis of the outputs of the torque sensors (1a and 1b, etc.), the first microcomputer (4B) determines the driving direction and torque of the DC motor (9) providing the assisting steering torque for the steering wheel, and outputs the torque signal (T) and the first direction signal (D1) for the DC motor (9). The second microcomputer (24B) generates the brake operation signal (B) on the basis of the outputs of the road wheel velocity sensors (21a through 21d) and the brake switch (22). Further, on the basis of the output of the torque sensors (1a and 1b), the microcomputer (24B) determines the direction of the DC motor (9), and outputs the second direction signal (D2).

Abstract: A correlation detector for images including: a unit for converting pixel signals of two images into digital data; a unit for deriving either an absolute value of a difference between the two pixel signals or a product of the two pixel signals from a table in accordance with pixel signal values of the two images; a unit for converting the derived value into an analog value; and a unit for storing electric charges while converting the converted analog value into a current value which is proportional to the converted analog value. Since the correlation between the two images are calculated using a table and the addition is performed in terms of storing electric charges, the correlation detector can be down-sized with simple circuits and its operation speed is improved as well.

Abstract: An electronic control apparatus for a vehicle includes first and second controllers between which the transmission of information is performed. A processor in the form of a microcomputer processes information transmitted from the first controller to the second controller and controls an actuator such as a brake actuator based on the information thus processed. An abnormality detecting circuit detects an interruption of signal transmission between the first and second controllers for a predetermined period of time, and it stops the control of the second controller on the actuator when it detects such an interruption. A transmission inhibitor is provided for inhibiting signal transmission from the second controller to the first controller when the abnormality detector detects an interruption.

Abstract: The invention provides a suction air amount measuring device for an engine wherein an operating constant of a binary digitizing circuit which is adapted to binary digitize an output of a Karman's vortex street flow rate sensor to produce Karman's vortex street pulses is changeably set in response to operating states of the engine. The measuring device thus has an effect that it can always produce correct Karman's vortex street pulses.Further, contents of a counter is latched at a timing of each of pulses produced by waveform shaping received waves phase modulated by Karman's vortex streets in order to phase demodulate the received waves to binary digitize the phase of the received waves. Accordingly, an effect can be attained that an inexpensive, small and lightweight flow rate measuring device wherein most parts of a signal processing means can be processed on the digital signal basis and can be formed into a digital IC can be provided.

Abstract: A method for effecting exhaust gas recirculation control in an exhaust gas recirculation control device of a type including a needle valve provided in an exhaust gas recirculation passage for determining the effective diameter of that passage, a position sensor for providing a signal representing the actual position of the needle valve, and a negative pressure motor for positioning the needle valve. In accordance with the invention, a target value for the needle valve is set according to predetermined operating conditions of the engine. The negative pressure motor is driven with a drive pulse having a time width corresponding to a positional deviation between the target value and the actual position of the needle valve as represented by the signal provided by the position sensor. After driving the negative pressure motor with one such drive pulse, the generation of the next subsequent drive pulse is inhibited for a predetermined period of time longer than the delay times in the device.

Abstract: An engine speed control apparatus includes speed and throttle sensors and an arithmetic unit which derives throttle values according to the difference between the desired speed and the actual speed. If part of the throttle operation loop becomes inoperative such that the desired throttle value differs from the actual throttle value by a given amount for a given time, a judgement circuit suspends the operation of the arithmetic unit until the throttle operation loop operates normally.

Abstract: A throttle opening control device includes a driver for controlling the opening of the throttle during idling and a judgment circuit or an idle switch for determining an idling condition and means for halting driver operation during non-idling intervals. In one embodiment, a sensor detects the throttle opening and supplies the same to a throttle driver by way of a difference circuit which forms a deviation value between the output of the sensor and that of an arithmetic unit whose operation is suspended during non-idling periods.