摘要:
An anti-skid control system for use in a motor vehicle having wheels whose rotational speeds are sensed by wheel sensors. The anti-skid control system decides the condition of the road-surface, on which the motor vehicle is running, on the basis of signals from wheel sensors. A reference speed is further calculated on the basis of the sensed speeds of the wheels symmetrically provided at the rear-right and rear-left sides with respect to the advancing direction of the motor vehicle. That is a selected one of an average value of the speeds of the rear-right and rear-left wheels sensed by the wheel sensors and the maximum one of the sensed rear-right and rear-left wheel speeds is selected in accordance with the decided road-surface condition. The reference speed is calculated on the basis of the selected one. A control unit of the anti-skid control system performs slip control of the wheels in accordance with the calculated reference speed. With this arrangement, the anti-skid control system can improve the braking efficiency and controllability irrespective of turning of the motor vehicle.
摘要:
An abnormality determining apparatus is applied to a vehicle motion control apparatus in which a vehicle behavior sensor (yaw rate sensor, etc.) is integrally mounted to an integrated unit that is integrally composed of an HU (hydraulic unit) and ECU. In this abnormality determining apparatus, the pattern of the vibration noise appearing on the output from the vehicle behavior sensor (output from yaw rate sensor Yrfilpc, etc.) is obtained when various actuators such as motor, solenoid valves, or the like, that are mounted to the HU, are operated with a predetermined pattern for a primary check for the HU. When the pattern of the vibration noise is not within the predetermined normal pattern range, it is determined, according to the abnormal manner of the pattern of the vibration noise, that the abnormality of the vehicle behavior sensor, abnormal operation of the actuator in the HU, or the like occurs.
摘要:
A relaying controller communicates with an external tool through a first communication path based on a first communication protocol and communicates with sub-controllers through a second communication path based on a second communication protocol, thus relaying communications between the external tool and the sub-controllers. The relaying controller includes a rewritable non-volatile memory having predetermined storage areas divided in correspondence with the sub-controllers. The relaying controller transmits, in response to a memory reading request from the sub-controller, a stored data in the corresponding storage area to the sub-controller through the second communication path, and writes, in response to a memory writing request from the sub-controller, a writing data received through the second communication path in the corresponding storage area. That is, the relaying controller executes accesses of the sub-controllers to the non-volatile memory.
摘要:
The invention is directed to an arrangement for monitoring a road condition which determines the coefficient of friction of the road surface on the basis of a signal corresponding to an acceleration of a vehicle detected by an acceleration sensor. The signal is converted into one of at least two predetermined values by conversion means in response to a magnitude of the acceleration every cycle of a predetermined time period. The converted value is summed up by summing means by a predetermined number of consecutive cycles to provide a total value in the last cycle thereof which is stored in memory means. Then, in determination means, one of at least two standard values is selected in response to the condition of increase or decrease of the total value in the present cycle provided by the summing means as compared with the total value in the previous cycle stored in the memory means. And, the total value in the present cycle is compared with the above one of at least two standard values to produce a road condition signal corresponding to a result of comparison which represents the coefficient of friction of the road surface. The present system is applicable to an anti-skid control system for an automotive vehicle.
摘要:
The anti-skid control system is provided with wheel velocity sensors only for the driving wheels and is capable of performing the anti-skid control through its accurate estimation of the vehicle speed and proper compensatory control even when sharp braking occurs immediately upon the release of the accelerator after the occurrence of acceleration slip. The anti-skid control system is capable of starting the anti-skid control with certainty even when the braking operation is not detected because of a failure in the operation of the brake switch. The system is provided with a fluid pressure generating device, a fluid pressure controlling device, a brake operation detecting device, an acceleration detecting device, a wheel velocity detecting device, a braking force controlling device, a first estimated vehicle speed setting device and a second estimated vehicle speed setting device.
摘要:
A wheel slipping control apparatus for controlling a braking hydraulic pressure to be applied to a wheel so as to perform an effective braking operation. The wheel slipping control apparatus comprises a control unit for generating a control signal in accordance with the wheel slipping state so as to perform a braking pressure control cycle so that the braking hydraulic pressure is set to a pressure decreasing mode and then to a pressure increasing mode. In the control unit, one of the braking pressure control cycles to be performed is determined as a learning control cycle to obtain a learning pressure-decreased value decremented in the learning control cycle and to obtain a learning pressure-increased value incremented in the learning control cycle. A present pressure-decreased value decremented in a control cycle after the learning control cycle is obtained to calculate a target pressure-increased value on the basis of the obtained learning pressure-decreased value and learning pressure-increased value whereby the braking hydraulic pressure is first increased to the vicinity of a wheel locking limit pressure after decreased in the pressure-decreasing mode.
摘要:
A multiplex communication system having a data repeater, which can prevent data from being lost so as to improve reliability of data communication, when a data repeater of a multiplex communication system repeats data. A multiplex communication system is made up of a plurality of communication groups including a plurality of communication lines and a data repeater. The data repeater is made up of receiving buffers, sending buffers, a data controller and a transfer-address table. The data controller selects multiplex communication lines through which the received data is to be repeated and transfers the received data thereto. The data controller has a priority-reset means for increasing a priority of a received data before being sent. The priority-reset means prioritizes a sending of the data from the data repeater, even if the data sent from the data repeater collides with the other data on the multiplex communication lines through which the received data is to be repeated. In this way, the priority-reset means prevents the data waiting for being sent in the data repeater from being lost by being overwritten with newly received data.
摘要:
A light sensing apparatus for different control systems includes a photosensitive element which generates a light current depending on light incident thereto. A pre-circuit connected to the photosensitive element is operative for generating separate basic signals in response to the light current generated by the photosensitive element. Processing circuits connected to the pre-circuit are active simultaneously for converting the basic signals generated by the pre-circuit into conversion-resultant signals having different forms respectively. The conversion-resultant signals are outputted to the control systems respectively. At least one of the processing circuits may include an oscillation circuit which oscillates at a frequency depending on related one of the basic signals generated by the pre-circuit.
摘要:
The anti-skid control system is capable of performing highly reliable anti-skid control through its accurate estimation of the vehicle speed and proper compensatory control even when sharp braking occurs or in the brake fluid pressure control on road surfaces with a low coefficient of friction likely to cause considerable fluctuations in wheel acceleration. The anti-skid control system is provided with a fluid pressure generating device, a fluid pressure controlling device, a wheel velocity detecting device, a standard speed setting device, a fluid pressure controlling mode setting device which sets either the pressure decrease mode or the pressure hold mode when the wheel velocity declines to a level lower than the standard speed and sets the pressure increase mode when the wheel velocity is equal to or higher than the standard speed. A maximum inflection point detecting device detects the maximum inflection point indicating the maximum value for the shift of the wheel velocity mentioned above from an increase to a decrease when the wheel velocity is not any lower than the standard speed. A fluid pressure controlling mode correcting device switches from the pressure increase mode mentioned above to either the pressure hold mode or the pressure decrease mode when the wheel velocity becomes equal to or higher than the standard speed and also becomes equal to or higher than the wheel velocity at the maximum inflection point.
摘要:
A vehicle anti-lock brake control apparatus including a two-position direction control valve disposed between a wheel brake cylinder and a hydraulic pressure source, for increasing and decreasing the brake cylinder pressure, a slip detector for detecting a slip condition of the wheel, a controller for controlling the valve so as to prevent excessive slipping of the wheel, an averaging device for obtaining an average value of the wheel acceleration during a period until the detected slip condition deteriorates to a predetermined reference condition, and a device for determining a pressure decrease time substantially in reverse proportion to the average value of the wheel acceleration obtained when the slip condition has deteriorated to the reference condition, and supplying the controller with the determined pressure decrease time.