Toshiaki Tsuyama

Bio: Toshiaki Tsuyama is an academic researcher from Mazda. The author has contributed to research in topics: Slip (vehicle dynamics) & Traction control system. The author has an hindex of 18, co-authored 74 publications receiving 1062 citations.

Traction control system for motor vehicle

Abstract: A traction control system for a motor vehicle having driving wheels and driven wheels. The traction control system comprises sensors for detecting a speed of each of the driving wheels of the vehicle; sensors for detecting a speed of each of the driven wheels of the vehicle; and a mechanism for calculating a slip value of the driving wheels based on the detected speeds of the driving and driven wheels. The traction control system also includes an engine output control mechanism for controlling each of the driving wheels so that the slip value of each of the driving wheels is controlled to become equal to a predetermined first desired slip value when the slip value of each driving wheel is greater than the predetermined first desired slip value; and a brake force control mechanism for controlling each of the driving wheels so that the slip value of each of the driving wheels is controlled to become equal to a predetermined second desired slip value when the slip value of each driving wheel is greater than the predetermined second desired slip value. The control system also includes an engine control restriction mechanism for restricting the engine output control mechanism while the braking control is carried out.

Slip control system for a vehicle

Abstract: When the driven wheel of the vehicle slips against the road surface to a large extent, such a large slip of the driven wheel can be converged by reducing torque to be applied to the driven wheel by slip control, i.e., by control the throttle valve for adjusting a load of the engine in a direction of forcibly closing the throttle valve prior to operation of the accelerator. In a region of the opening angle of the accelerator nearby its full open region, for example, accounting for 75% or more, a control-unreactive region is provided which is unreactive to slip control, thereby preventing the throttle valve from lowering a given opening angle, for example, 25%. This arrangement can retain the opening angle of the accelerator nearby its full open position even if slip control cannot work normally, thereby ensuring an open state of the throttle valve and allowing the vehicle to run at least to a tune-up factory nearby.

Slip control system for motor vehicle

Abstract: A slip control system for a motor vehicle controls respective braking forces in right and left driving wheels and controls an engine output by controlling a throttle opening of a throttle valve so that a slip value of the driven wheel becomes less than a target slip value. The system includes a device providing a basic control amount of the throttle opening based on the slip value of the driven wheel and the target slip value, a device for detecting respective brake fluid pressures in the right and left driven wheels, a device for converting the detected brake fluid pressure into an engine output, a device for providing a correction control amount of the throttle opening by subtracting an amount of the throttle opening corresponding to the converted engine output from the basic control amount of the throttle opening, and a device for driving the throttle valve by the basic control amount of the throttle opening when the brake fluid pressures in the right and left driven wheels are increased or increased rapidly, and driving the throttle valve by the correction control amount of the throttle opening when the brake fluid pressures in the right and left driven wheels are not increased or increased rapidly.

Attitude control device for vehicle

Abstract: PROBLEM TO BE SOLVED: To satisfy attitude control together with vehicle braking in a high level while avoiding spin by providing a cooperative control means correcting posture control and adding brake control distribution to it according to the stepping pressure of a brake pedal, and adding regulation to the cooperative means at detecting spin of a vehicle. SOLUTION: A vehicle body sideslip angle is computed out of vehicle body speed computed from respective wheel speed detected by wheel speed sensors 6,... together with lateral acceleration by a lateral G sensor 7, yaw rate by a yaw rate sensor 8, and steering angle by a steering angle sensor 9. From these, the slip ratio, the slip angle, the load factor, and the road surface friction coefficient of each tire 23 are computed, deviation quantities from a target yaw rate and a target sideslip angle are computed based on these, and intervention judgement of posture control is executed. According to the judged result, braking force of each wheel 21 is computed so as to converge the turning posture of a vehicle toward the target running direction. The degree of brake control to promote spin is reduced, and hence the spin is avoided. COPYRIGHT: (C)1998,JPO

Slip control system for automotive vehicle

Abstract: A slip of the driven wheels is converged by causing the torque generated by the engine to be reduced and applying braking force when a slip of the driven wheel becomes large during accelerating. Control of the application of the braking force to the left-hand and right-hand driven wheels is made individually and separately from each other. When such an incident occurs as causing no normal control of decreasing the torque generated by the engine to be made, the contents of control of application of the braking force is changed so as to apply the same degrees of the braking force to both of the left-hand and right-hand driven wheels.

Electric power-steering device

Abstract: An electric power-steering device has a speed-reducing mechanism (17) for reducing the speed of an output shaft (16) of an electric motor (15). The speed-reducing mechanism (17) has an internal gear (39) engaged and rotated with the output shaft (16) and an external gear (40) with which the internal gear (39) internally meshes. A drive pulley (41) rotatable together with the external gear (40) and a driven pulley (42) provided so as to surround a steering shaft are connected by an endless belt (43). Speed reduction is obtained by the internal gear (39) and the external gear (40), and the speed-reducing mechanism (17) as a whole achieves a high reduction ratio without greatly reducing the diameter of the drive pulley (41).

Vehicle Control System

Abstract: A vehicle control system which can ensure high reliability, real-time processing, and expandability with a simplified ECU configuration and a low cost by backing up an error through coordination in the entire system without increasing a degree of redundancy of individual controllers beyond the least necessary level. The vehicle control system comprises a sensor controller for taking in sensor signals indicating a status variable of a vehicle and an operation amount applied from a driver, a command controller for generating a control target value based on the sensor signals taken in by the sensor controller, and an actuator controller for receiving the control target value from the command controller and operating an actuator to control the vehicle, those three controller being interconnected via a network. The actuator controller includes a control target value generating unit for generating a control target value based on the sensor signals taken in by the sensor controller and received by the actuator controller via the network when the control target value generated by the command controller is abnormal, and controls the actuator in accordance with the control target value generated by the control target value generating unit.

Method and apparatus for inertial guidance for an automobile navigation system

Abstract: The present invention discloses an improved vehicular inertial guidance navigation system, a.k.a. a dead reckoning system for navigation of a vehicle. The inertial guidance navigation system which may be used alone or in combination with other position determination means, such as GPS and map databases, to determine the location of a vehicle. The dead reckoning system has several advantages over existing systems. First, it can be easily mounted to the chassis of any vehicle. Second, it does not require any interface with existing sensors on the vehicle. Third, the system contains logic for removing errors in the position and heading determinations, brought about by angulation/rotation of the chassis and inertial guidance sensors, brought about by inclination or tilt of the chassis, with respect to an inertial/quasi-inertial frame of reference, such as the earth. The inertial guidance system includes: an inertial guidance sensor, a translation unit, and a logic unit. The inertial guidance sensor is suitable for coupling to the vehicle. The inertial guidance sensor senses motion of the vehicle in a non-inertial frame of reference and forming a sensor signal corresponding thereto. The translation unit is coupled to receive the sensor signal formed by the inertial guidance sensor. The translation unit translates the sensor signal into a quasi-inertial frame of reference and forms a translated signal corresponding thereto. The logic unit receives the translated signal formed by the translation unit and converts converting the translated signal into an estimated position and heading of the vehicle.

Brake control system

Abstract: A brake system control for use in a vehicle with four wheels comprising the steps of: determining a desired yaw rate (454); determining a yaw torque command responsive to the desired yaw rate (806); if the vehicle is in an anti-lock braking mode during driver commanded braking, applying the yaw torque command to only one of the four wheels to release brake pressure in said one of the four wheels (258-266, 274, 278, 280, 410-418); if the vehicle is in a positive acceleration traction control mode during driver commanded acceleration, applying the yaw torque command to only one of the four wheels to apply brake pressure in said one of the four wheels (258-266, 288-292, 410-418); and if the vehicle is not in the anti-lock braking mode or in the positive acceleration traction control mode, then: (i) determining whether a vehicle brake pedal is depressed (370); (ii) if the vehicle brake pedal is depressed, applying brake force to the vehicle wheels responsive to the depression of the brake pedal (374, 412, 418), wherein the applied brake force is modified to at least two of the vehicle wheels to create a left-right brake torque differential responsive to the yaw torque command.

System for predicting behavior of automotive vehicle and for controlling vehicular behavior based thereon

Abstract: A system for detecting a physical amount of behavior of a vehicle includes, acceleration sensors arranged on at least two longitudinal axes of the vehicle, the vertical axis Of the vehicle and the lateral axis of the vehicle, a plurality of the acceleration sensors being disposed on each of the axes. A unit is provided for establishing a conversion equation for determining acceleration values of linear motion at an arbitrary point of the vehicle in the direction of each axis of an arbitrary coordinate system and acceleration values of rotational motion with respect to the each axis of the coordinate system while simultaneously using acceleration values detected by the acceleration sensors disposed on at least two of the vehicular longitudinal axes, the vertical axis and the lateral axis. There is also provided a unit for calculating the conversion equation to obtain the acceleration values of linear motion at an arbitrary point of the vehicle in the direction of each axis of the arbitrary coordinate system and acceleration values of rotational motion with respect to each axis of the coordinate system, a unit for establishing a motion equation expressing a plurality of freedom motions, and a unit for calculating the motion equation with the acceleration values of linear motion at an arbitrary point of the vehicle in the direction of each axis of the arbitrary axis of the arbitrary coordinate system and acceleration values of rotational motion with respect to the each axis of the coordinate system to obtain the physical amount associated with the behavior of the vehicle.