Wheel speed sensor

Abstract: A parking assistance system is mounted in a vehicle, and has an image pick-up with a single camera, an image processing device, a display, a steering angle sensor, a wheel speed sensor, and a pulse counter. An A/D converter subjects two analog images picked up by the image pick-up at different locations to A/D conversion, and sends the results to frame memories. A CPU uses the digital image data and the transition data of the vehicle to calculate object data and a distance from the vehicle to the 3D object. An image thus obtained is then converted into a view from the above. The view from the above is stored in a frame memory, and outputted to the display under the control of a controller for display.

Abstract: This paper proposes a sensor fusion-based low-cost vehicle localization system. The proposed system fuses a global positioning system (GPS), an inertial measurement unit (IMU), a wheel speed sensor, a single front camera, and a digital map via the particle filter. This system is advantageous over previous methods from the perspective of mass production. First, it only utilizes low-cost sensors. Second, it requires a low-volume digital map where road markings are expressed by a minimum number of points. Third, it consumes a small computational cost and has been implemented in a low-cost real-time embedded system. Fourth, it requests the perception sensor module to transmit a small amount of information to the vehicle localization module. Last, it was quantitatively evaluated in a large-scale database.

Abstract: A system and method for maintaining a vehicle at a predetermined velocity on a graded surface is provided, which includes a propulsion system to supply motive torque to a vehicle wheel, a vehicle stability sensor, and a control system adapted to receive signal input from the vehicle stability sensor. The control system controls magnitude of the motive torque supplied to the wheel. The propulsion system may include an electric wheel motor powered by an electrical energy storage system, a hybrid powertrain system, and an internal combustion engine and transmission. The vehicle stability sensor determines orientation of the vehicle relative to a horizontal plane, including a longitudinal acceleration sensor and a virtual longitudinal acceleration sensor. The control system receives inputs from a wheel speed sensor, an accelerator pedal sensor, and a brake pedal sensor to control motive torque. Motive torque is controlled to maintain wheel speed sensor at a null output.

Abstract: PROBLEM TO BE SOLVED: To adequately set the target brake torque irrespective of any disturbance to a control system, any state change of the external side, and to prevent the braking force from being unnecessarily reduced. SOLUTION: The brake control device 10 includes a wheel deceleration computation unit 53a for calculating the wheel deceleration GRe by the wheel speed detected by a wheel speed sensor 45 during the previous computation of the estimated deceleration GRDV of a vehicle body by a vehicle body deceleration computation unit 52, and the wheel speed detected by the wheel speed sensor 45 during the present computation, and an estimated vehicle body deceleration computation unit 53b for calculating the estimated vehicle body deceleration GRv. The vehicle body deceleration computation unit 52 computes the estimated deceleration GRDV of the vehicle body by executing the correction by the correction coefficient KD according to the ratio of the wheel deceleration GRe to the estimated vehicle body deceleration GRv. The correction coefficient KD is corrected so that the estimated deceleration GRDV is larger after the correction than before the correction when the wheel deceleration GRe is larger than the estimated vehicle body deceleration GRv. COPYRIGHT: (C)2010,JPO&INPIT