Abstract: A method is provided for estimating vehicle velocity for a vehicle using a single-antenna global positioning system (GPS). An absolute speed and a course angle of the vehicle is measured using the single-antenna GPS. The yaw rates of the vehicle are measured independently of the GPS. An integrated yaw rate of the vehicle is calculated as a function of the measured yaw rates over a period of time. A yaw angle is determined as a function of a reference yaw angle and the integrated yaw rate. Aside slip angle is calculated as a function of the estimated yaw angle and the course angle provided by the GPS. The vehicle velocity is determined as a function of the absolute speed and the side slip angle. The vehicle velocity is provided to a vehicle dynamic control application.

Abstract: Systems, processes, and techniques for calibrating an onboard sensor of a vehicle are presented here. The vehicle has a control system that is capable of performing at least some of the tasks related to the calibration procedure. An exemplary methodology collects vehicle status data and obtains navigation map data during operation of the vehicle. A current calibration factor is calculated for the onboard sensor, based on the collected vehicle status data and the obtained navigation map data. More specifically, the vehicle status and navigation map data can be used to determine when the current conditions are suitable for performing calibration. When the current conditions are satisfactory, the calibration factor is calculated. Thereafter, the onboard sensor can be calibrated in response to the current calibration factor.

Abstract: A system according to the principles of the present disclosure includes a longitudinal acceleration estimation module, a vehicle longitudinal acceleration sensor, a road grade estimation module, and an actuator control module. The longitudinal acceleration estimation module estimates a longitudinal acceleration of a vehicle based on at least one of a transmission output speed and a wheel speed. The vehicle longitudinal acceleration sensor measures the longitudinal acceleration of the vehicle. The road grade estimation module estimates a grade of a road on which the vehicle is traveling based on the estimated longitudinal acceleration and the measured longitudinal acceleration. The actuator control module controls an actuator of the vehicle based on the estimated road grade.

Abstract: Methods and systems are provided for assessing understeer for a vehicle having at least one rear wheel and at least one front wheel. Rear wheel speeds are measured from the rear wheels, and front wheel speeds are measured for the front wheels. A determination is made as to the understeer of the vehicle using a comparison of the front wheel speeds and the rear wheel speeds.

Abstract: A diagnostic method for improving the reliability, accuracy, efficiency and/or robustness of a vehicle dynamic control system (VDCS) by providing analytical redundancy for one or more sensor readings. Sensor readings such as wheel speed, yaw rate, lateral acceleration, longitudinal acceleration and steering angle are oftentimes related to one another. Thus, the diagnostic method may use these dynamic relationships to detect faults in the sensor readings without having to add additional redundant hardware or use complex circular logic structures, which can increase the cost and impose processing burdens on the VDCS. In an exemplary embodiment, the diagnostic method checks for faulty sensor readings through a process of analytical redundancy that includes intra- and inter-parameter evaluations having linear and forward dependencies.

Abstract: Systems and methods for detecting road bank and determining road bank angle include determining a road bank angle as a function of difference in slip angle where the difference in slip angle is a function of difference in course angle and difference in yaw angle.

Abstract: Methods and systems are provided for assessing movement of a vehicle having a plurality of wheels. A plurality of wheel direction values are obtained. Each of the wheel direction values pertains to a direction of wheel rotation of a respective wheel. An average value of the wheel direction values is calculated. A direction of movement of the vehicle is obtained via a controller using the average value. In addition, a signed velocity is determined for and indicative of both forward and reverse motions using the wheel direction values.

Abstract: Methods for operating a control system of a vehicle and vehicle systems are provided. A method includes receiving a first output signal from a longitudinal accelerometer during a first travel condition of the vehicle including a first vehicle speed of the vehicle and a first road grade substantially equal to zero, wherein the first vehicle speed is a constant speed and the first output signal represents a first measurement including a first vehicle acceleration component and a bias offset component, receiving a second output signal during a second travel condition of the vehicle including a second vehicle speed of the vehicle and a second road grade, wherein the second output signal represents a second measurement including a second vehicle acceleration component and the bias offset component, and determining the bias offset component and gravity component to obtain an estimated road grade factor.

Abstract: Methods and systems are provided for assessing understeer for a vehicle having at least one rear wheel and at least one front wheel. Rear wheel speeds are measured from the rear wheels, and front wheel speeds are measured for the front wheels. A determination is made as to the understeer of the vehicle using a comparison of the front wheel speeds and the rear wheel speeds.

Abstract: A method of estimating a speed of a vehicle is provided. The vehicle has a wheel and the method comprises receiving a first wheel speed signal indicating a rotation rate of the wheel, determining a first calculated forward speed of the vehicle based on the first wheel speed signal, receiving a first steering signal, determining the first steering signal contains information indicating large steering activity, receiving a second wheel speed signal at a later time than the first wheel speed signal, and determining, in response to receiving the first steering signal, a second calculated forward speed of the vehicle that is based on the second wheel speed signal and the first calculated forward speed.

Abstract: A diagnostic method for improving the reliability, accuracy, efficiency and/or robustness of a vehicle dynamic control system (VDCS) by providing analytical redundancy for one or more sensor readings. Sensor readings such as wheel speed, yaw rate, lateral acceleration, longitudinal acceleration and steering angle are oftentimes related to one another. Thus, the diagnostic method may use these dynamic relationships to detect faults in the sensor readings without having to add additional redundant hardware or use complex circular logic structures, which can increase the cost and impose processing burdens on the VDCS. In an exemplary embodiment, the diagnostic method checks for faulty sensor readings through a process of analytical redundancy that includes intra- and inter-parameter evaluations having linear and forward dependencies.

Abstract: Methods and systems are provided for assessing movement of a vehicle having a plurality of wheels. A plurality of wheel direction values are obtained. Each of the wheel direction values pertains to a direction of wheel rotation of a respective wheel. An average value of the wheel direction values is calculated. A direction of movement of the vehicle is obtained via a controller using the average value. In addition, a signed velocity is determined for and indicative of both forward and reverse motions using the wheel direction values.

Abstract: Systems and methods for detecting road bank and determining road bank angle include determining a road bank angle as a function of difference in slip angle where the difference in slip angle is a function of difference in course angle and difference in yaw angle.

Abstract: A system, method and computer program product is provided for estimating the lateral velocity of a vehicle. The method comprises providing a plurality of estimation structures, each estimation structure corresponding to one of a plurality of dynamic regions in which a vehicle may operate, determining in which of the plurality of dynamic regions the vehicle is operating to identify a first dynamic region, and generating a first regional lateral velocity estimation from a first estimation structure corresponding to the first dynamic region.

Abstract: A method is provided for estimating vehicle velocity for a vehicle using a single-antenna global positioning system (GPS). An absolute speed and a course angle of the vehicle is measured using the single-antenna GPS. The yaw rates of the vehicle are measured independently of the GPS. An integrated yaw rate of the vehicle is calculated as a function of the measured yaw rates over a period of time. A yaw angle is determined as a function of a reference yaw angle and the integrated yaw rate. Aside slip angle is calculated as a function of the estimated yaw angle and the course angle provided by the GPS. The vehicle velocity is determined as a function of the absolute speed and the side slip angle. The vehicle velocity is provided to a vehicle dynamic control application.

Abstract: A method for operating a vehicle electronic stability control (“ESC”) system utilizing values for a variable obtained from a primary source and a redundant source includes the steps of receiving a first value for the variable from the primary source, receiving a second value for the variable from the redundant source, generating a normalized value as a function of the first value and the second value, determining whether the primary source is operating correctly, utilizing the first value for operation of the vehicle ESC system if the primary source is operating correctly, and utilizing the second value for operation of the vehicle ESC system if the primary source is not operating correctly and the second value is not greater in absolute value than the normalized value.

Abstract: Methods for operating a control system of a vehicle and vehicle systems are provided. A method includes receiving a first output signal from a longitudinal accelerometer during a first travel condition of the vehicle including a first vehicle speed of the vehicle and a first road grade substantially equal to zero, wherein the first vehicle speed is a constant speed and the first output signal represents a first measurement including a first vehicle acceleration component and a bias offset component, receiving a second output signal during a second travel condition of the vehicle including a second vehicle speed of the vehicle and a second road grade, wherein the second output signal represents a second measurement including a second vehicle acceleration component and the bias offset component, and determining the bias offset component and gravity component to obtain an estimated road grade factor.

Abstract: A method of estimating a speed of a vehicle is provided. The vehicle has a wheel and the method comprises receiving a first wheel speed signal indicating a rotation rate of the wheel, determining a first calculated forward speed of the vehicle based on the first wheel speed signal, receiving a first steering signal, determining the first steering signal contains information indicating large steering activity, receiving a second wheel speed signal at a later time than the first wheel speed signal, and determining, in response to receiving the first steering signal, a second calculated forward speed of the vehicle that is based on the second wheel speed signal and the first calculated forward speed.

Abstract: A method for measuring and storing values of sensor bias in acceleration values for a vehicle, obtained over a plurality of time periods from a sensor having a specified range of expected variability of sensor bias values, includes measuring a first value of sensor bias obtained during operation of the vehicle in a first time period, storing the measured first value of sensor bias for use in one or more subsequent time periods, measuring a second value of sensor bias obtained during operation of the vehicle in a second time period, subtracting the measured second value of sensor bias from the stored first value of sensor bias, thereby generating a sensor bias difference, and storing the measured second value of sensor bias, for reference in one or more subsequent time periods, if the sensor bias difference is within the specified range of expected variability of sensor bias values.

Abstract: A method and system, according to one embodiment of the present invention, provide a means to accurately determine the velocity of a vehicle. An initial estimation of the velocity of the vehicle is calculated based on rates of rotation of a plurality of wheels on the vehicles. If any of the wheels on the vehicle are in a brake control, or traction control, situation, the initial estimation is modified based on an acceleration of the vehicle to generate a modified estimation of the velocity of the vehicle.