摘要:
An improved method of operation for a motor vehicle automatic transmission determines a vehicle speed for purposes of selecting a desired transmission gear at least in part based on the wheel speeds of the vehicle. If the vehicle is being operated in a two-wheel drive mode, the vehicle speed is determined based on an average of the speeds of the un-driven wheels; if the vehicle is being operated in a four-wheel drive mode, the vehicle speed is determined based on the lowest of the four wheel speeds. Optionally, the wheel speeds are only used to determine vehicle speed if the Reverse range of the transmission has been engaged within a specified time interval, and otherwise the vehicle speed is determined based on an output speed of the transmission.
摘要:
The present invention is directed to an apparatus for estimating the peak of a coefficient of friction in a coefficient of friction—slip rate characteristic, wherein a wheel acceleration of each wheel of a vehicle is detected, and a vehicle acceleration of the vehicle is detected. A peak estimation device is provided for estimating the peak of the coefficient of friction, and adapted to determine that the coefficient of friction is the peak when the wheel acceleration is lower than the vehicle acceleration, by more than a predetermined difference. An anti-skid control system for an automotive vehicle may be formed to include the coefficient of friction peak estimation apparatus, and a reference speed setting device for setting a reference speed for initiating a pressure decrease mode on the basis of a wheel speed and a vehicle speed detected when the peak was detected. A pressure control device is disposed between a wheel brake cylinder and a pressure generator, to be controlled in response to at least the result of comparison between the wheel speed and the reference speed.
摘要:
A method and system for controlling a vehicle includes receiving vehicle position information from a positioning system and combining the position information with information from a map database and a driver behavior model to control the vehicle's speed and braking for not only the current roadway the vehicle is operating on but also on upcoming road sections.
摘要:
Vehicle motion control devices and methods systematically treat a conditions of each wheel to acquire and maintain the vehicle behavior stability together with anti wheel lock and wheel spin processing, braking forces distribution. Device for controlling a running behavior of a vehicle estimates a road reaction force on each wheel, calculates a yaw moment around a centroid of the vehicle body generated by the road reaction force on each wheel, and controls driving and braking forces on each wheel based upon the yaw moments so as to stabilize a running of the vehicle. Spin and Drift conditions are detected through presently generated yaw moments and critical yaw moments which can be generated by a road reaction force assumed to be maximized. Physical parameters of each wheels, required for detecting and controlling the behavior of the vehicle are estimated with a theoretical tire model.
摘要:
The vehicle deceleration control apparatus controls deceleration given to a vehicle according to a distance from a vehicle ahead, which is directly measured or estimated based on an accelerator operating condition, so that the smaller the distance from a vehicle ahead, the greater is an assist deceleration. The vehicle deceleration control apparatus is capable of giving an appropriate deceleration according to traffic conditions.
摘要:
An automotive brake control system with an anti-brake skid (ABS) unit which controls a wheel-brake cylinder pressure to each individual wheel cylinder of the road wheels to prevent a wheel lock-up condition during braking, and an ABS control unit being configured to be connected electrically to at least wheel speed sensors and the ABS unit to execute skid control having at least a reduce-pressure operating mode and a pressure build-up operating mode, when the wheel speed sensor signals indicate that at least one of the road wheels is locking up. The ABS control unit includes a road-surface-condition change determination section which determines, based on both a time length of brake-fluid-pressure control continuously executed during the skid control and a recovery acceleration of the wheel speed of the road wheel subjected to the skid control, whether there is a road-surface &mgr; change from low-&mgr; road to high-&mgr; road.
摘要:
Method and device for controlling the braking action of at least one wheel brake of a four-wheel-drive motor vehicle having at least one rear axle and one front axle. A first rpm signal representing the speeds of rotation of the front-axle wheels and a second rpm signal representing the speeds of rotation of the rear-axle wheels are detected. The difference between the first and second rpm signals is then determined, and braking action is controlled as a function of the difference that has been determined.
摘要:
An apparatus for judging road surface gradients including a speed detector for periodically detecting wheel speeds of four wheels of a vehicle, a vehicle body speed calculator for obtaining a vehicle body speed of the vehicle, a slip rate calculator for obtaining a slip rate, a vehicle body acceleration calculator for obtaining an acceleration of the vehicle body of the vehicle, a determining device for determining whether the acceleration of the vehicle body is within a specified range proximate to zero, and a gradient judging device for judging a gradient of a road surface depending on the determination of the determining device. The gradients of road surfaces might be judged without using various sensors but only on the basis of information which can be obtained from a speed detector for detecting wheel speeds.
摘要:
The present invention is directed to a system for detecting a difference in level on a road, wherein an acceleration sensor is provided for detecting an acceleration of a vehicle, and a wheel speed sensor is provided for detecting a wheel speed of at least one wheel of the vehicle. A wheel acceleration is calculated continuously on the basis of the wheel speed detected by the wheel speed sensor. It is determined if a variation of the signal output from the acceleration sensor is greater than a predetermined range. And, it is determined if the calculated wheel acceleration varied in the same direction as that of the variation of the signal output from the acceleration sensor, and then varied in the reverse direction to exceed a predetermined reference value. On the basis of the result of each determination, it is determined if the wheel ran over the difference in level on the road. If the affirmative result is obtained in each determination, the difference in level on the road can be detected.
摘要:
A process and device for controlling a vehicle brake system, in which a central controller and a plurality of other decentralized control units are provided. This system is initialized from the central controller over the communication connecting the control units, at least by transferring corresponding addresses. When the brake pedal is actuated before or during the initializing phase, the brake system is electronically controlled as a function of specified reference values even if the system initialization has not yet been carried out or was not completely carried out.