279 results about "Yaw-rate sensor" patented technology

A control system or method for a vehicle references a camera and sensors to determine when an offset of a yaw rate sensor may be updated. The sensors may include a longitudinal accelerometer, a transmission sensor, a vehicle speed sensor, and a steering angle sensor. The offset of the yaw rate sensor may be updated when the vehicle is determined to be stationary by referencing at least a derivative of an acceleration from the longitudinal accelerometer. The offset of the yaw rate sensor may be updated when the vehicle is determined to be moving straight by referencing at least image data captured by the camera. Lane delimiters may be detected in the captured image data and evaluated to determine a level of confidence in the straight movement. When the offset of the yaw rate sensor is to be updated, a ratio of new offset to old offset may be used.

A semiconductor type yaw rate sensor has a substrate, a beam structure formed from a semiconductor material and having at least one anchor portion disposed on the substrate, a weighted portion located above the substrate a predetermined gap therefrom, and a beam portion which extends from the anchor portion and supports the weighted portion. A movable electrode is formed onto the weighted portion, and a fixed electrode is formed on the substrate in such a manner that the fixed electrode faces the movable electrode. When a drive voltage is applied between the movable electrode and the fixed electrode, the beam structure is forcibly caused to vibrate in a direction that is horizontal relative to a substrate surface plane. In this yaw rate sensor, a strain gauge to monitor forced vibration of the beam structure is formed in the beam portion. As a result, the forced vibration of the beam structure can be monitored with a simple structure.

Yaw rate sensors are provided, the use of which permits quantitative measurement of yaw rate. The yaw rate sensor comprises at least a base, a first suspension and a second suspension with a proof mass supported between the two suspensions, which together form a resonator. The first suspension has a pair of thin-wire driving electrodes double side patterned on the surfaces. When a driving voltage is applied to the driving electrodes, it imposes an electric field to piezoelectrically induce a driving resonance. When the sensor is rotated around its sensing axis, the resonator will be forced to generate a sensing resonance out of the driving resonance plane to compensate the change in the linear momentum which must be conserved. The piezoelectric charge signal generated by the sensing resonance on the sensing electrodes which are double side patterned on the surfaces of the second suspension is used to detect the yaw rate. Specifically, the amplitude of the sensing resonance is in proportion to the yaw rate. The structure of the yaw rate sensors of this invention is suitable for mass production by lithographic micromachining techniques at low cost.

A yaw angle return controller is configured to end first yaw angle return control at a predetermined time when a value which is calculated by adding yaw angle detected by a lane recognition device at a predetermined time and an estimated yaw angle change amount is the same as yaw angle at lane change start time under a state where the first yaw angle return control is being executed. The predetermined time comes after the first start time and before the first finish time. The estimated yaw angle change amount is calculated by multiplying the yaw rate detected by a yaw rate sensor at the predetermined time by a predetermined time period for foreseeing.

A bank angle detecting device includes a roll rate sensor for detecting a angular velocity ωr about a longitudinal axis of the motorcycle; a yaw rate sensor for detecting a angular velocity ωy about an vertical axis of the motorcycle; a bank angle detecting unit for detecting the motorcycle bank angle δ for calibration use based on the yaw rate ωy and a traveling velocity v; and a bank angle correcting unit for correcting the basic motorcycle bank angle δr, determined from an output ωr of the yaw rate sensor, so as to approach the motorcycle bank angle δ that is detected by the bank angle detecting unit, to thereby determine the estimated bank angle δ0.

A system and method for calibrating a vehicle heading sensor, such as a yaw-rate sensor, when GPS signals are not available using a bias update model that employs a bias gain factor. In order for the bias update model to be accurate, the vehicle should be traveling relatively straight. One embodiment of the present invention uses three thresholds to determine if the vehicle is traveling straight. These thresholds include a yaw-rate threshold, a steering wheel angle threshold and a wheel speed threshold. If all three of the thresholds indicate that the vehicle is traveling straight, then the update bias model can be used to calibrate the yaw-rate sensor.

A system (18) for controlling a safety system (44) of an automotive vehicle (10) includes a longitudinal acceleration sensor (36), a vehicle speed sensor (20), a lateral acceleration sensor (32), a yaw rate sensor, and a controller (26). The controller (26) determines a stability index and provides a first observer that determines a reference longitudinal velocity in response to the longitudinal acceleration signal, the yaw rate signal, a pitch attitude and vehicle speed from wheel speed sensors. The controller (26) determines a reference lateral velocity in response to the lateral acceleration signal, the yaw rate signal, a roll attitude, a pitch attitude and vehicle speed from the wheel speed sensors. The controller provides a second observer that determines a second longitudinal velocity in response to the longitudinal acceleration signal, the yaw rate signal, a lateral velocity, the pitch attitude and a first adjustment based on the longitudinal reference velocity. The controller determines a second lateral velocity in response to the lateral acceleration signal, the yaw rate signal, a roll attitude, a pitch attitude and a second adjustment based on the lateral reference velocity. The controller determines an output lateral velocity and an output longitudinal velocity in response to the first observer, second observer and the stability index. The controller controls the safety system in response to the output lateral velocity and the output longitudinal velocity.

A vehicular motion control apparatus uses a steering angle detected by a steering angle sensor capable of detecting an absolute rotational angle. This control apparatus has a yaw rate sensor. If a reference rotational position of the steering angle sensor has not been determined, the control apparatus calculates a plurality of target yaw rates on the basis of a plurality of steering angles estimated from a steering angle detected by the steering angle sensor, and controls motion of a vehicle on the basis of the minimum one of differences between the target yaw rates and an actual yaw rate. The control apparatus determines a reference rotational position of the steering angle sensor on the basis of a steering angle corresponding to the minimum one of the differences, and then calculates a steering angle for motion control on the basis of the detected steering angle and the determined reference rotational position.

A side rearview mirror control system for a vehicle that automatically changes a rear viewing angle of a side rearview mirror. The control system receives various vehicle inputs to determine if and when a vehicle operator will turn the vehicle, make a lane change, merge into a lane of traffic, etc. The system pivots the mirror to eliminate a potential blind spot during these conditions. In one embodiment, the rear view mirror control system receives input signals from a vehicle hand-wheel angle sensor, a vehicle yaw rate sensor, a vehicle speed sensor, a turn signal indicator, a global positioning system (GPS) receiver and map information to determine whether the vehicle is turning or will be turning.

A system and method for calibrating the bias and scale factors of a heading rate sensor, such as a yaw-rate sensor, using GPS signals. The system receives wheel speed or rotation signals, a vehicle odometer reading, GPS signals and yaw-rate signals. The system includes a wheel-slip detection processor that determines whether there is wheel-slip based on the wheel speed signals and the GPS signals. The system also includes a wheel-based acceleration processor that estimates vehicle acceleration. The system also includes a differential odometry processor that determines vehicle heading based on wheel speed. The system also includes a GPS reference data validation processor that determines whether the GPS signals are valid using the estimated vehicle acceleration and wheel speeds. The valid GPS signals are then used to calibrate the yaw-rate sensor signals, which can be used for vehicle heading purposes.

A micromechanical yaw-rate sensor comprising a first yaw-rate sensor element, which outputs a first sensor signal, which contains information about a rotation around a first rotational axis, a second yaw-rate sensor element, which outputs a second sensor signal, which contains information about a rotation around a second rotational axis, which is perpendicular to the first rotational axis, a drive, which drives the first yaw-rate sensor element, and a coupling link, which mechanically couples the first yaw-rate sensor element and the second yaw-rate sensor element to one another, so that driving of the first yaw-rate sensor element also causes driving of the second yaw-rate sensor element.

A software compass used during a GPS outage calculates vehicle heading and presents it upon request. The software compass gathers information from a yaw rate sensor, wheel steering angle sensor, wheel speed sensor, and PRNDL gear position sensor to calculate vehicle heading using a weighting algorithm. Because the yaw rate sensor data is a central factor in calculating vehicle heading, the quality of calibration of the yaw rate sensor is of importance. The disclosed calibration algorithm calculates the yaw rate bias and scale factors to calibrate the yaw rate sensor.

A vehicle stability control system diagnostic strategy, wherein the diagnostic strategy may be adaptively applied based upon the identified maneuver states of the vehicle. The diagnostic architecture contains three vehicle state observers (i.e., models) each based on inputs from only two of the three sensors (yaw rate, lateral acceleration and hand wheel angle). More particularly, the first observer does not consider lateral acceleration input. The second observer does not consider yaw rate sensor input and the third does not consider hand wheel angle (HWA) sensor input in determining the vehicle state. However, estimated vehicle speed input is used by all the observers. For example, the first observer detects a maneuver state based on yaw rate and HWA and vehicle speed inputs. Then it diagnoses the lateral acceleration sensor failure based on the observer output. The diagnostics are based on vehicle dynamics correlations that hold in steady state linear range conditions. Similarly, the other two observers detect maneuver state and diagnose the respective signals. Advantageous variants include the use of a proactive sensor diagnostics strategy that provides increased coverage during steady state linear range maneuvers while simultaneously detecting faults within the required fault response time.

A control system (18) and method for an automotive vehicle (10) includes a pitch rate sensor (37) generating a pitch rate signal, a longitudinal acceleration sensor (36) generating a longitudinal acceleration signal, and a yaw rate sensor (28) generating a yaw rate signal. A safety system (44) and the sensors are coupled to a controller. From the sensors, the controller (26) determines an added mass and a position of the added mass, a pitch gradient and/or a pitch acceleration coefficient that takes into account the added mass and position. The controller controls a vehicle system in response to the added mass and the position of the added mass, the pitch gradient and/or pitch acceleration coefficient variables.