Abstract: A system and method for enhancing vehicle diagnostic and prognostic algorithms and improving vehicle maintenance practices. The method includes collecting data from vehicle components, sub-systems and systems, and storing the collected data in a database. The collected and stored data can be from multiple sources for similar vehicles or similar components and can include various types of trouble codes and labor codes as well as other information, such as operational data and physics of failure data, which are fused together. The method generates classes for different vehicle components, sub-systems and systems, and builds feature extractors for each class using data mining techniques of the data stored in the database. The method also generates classifiers that classify the features for each class. The feature extractors and feature classifiers are used to determine when a fault condition has occurred for a vehicle component, sub-system or system.

Abstract: A system and method for providing component and sub-system state of health prognosis in a complex system using fault models and component aging models. The method includes determining a current state of health value for a sub-system using fault signature test results and determining current state of health values for a plurality of components in the sub-system using the fault signature test results. The method also determines current state of health values for components in the system that cannot use fault signature test results using a first probability model and the current state of health values for the plurality of components. The method determines predicted future state of health values for the components in the sub-system using component aging models and determines a predicted future state of health value for the sub-system using a second probability model and the future state of health values of the components.

Abstract: A system and method for determining the health of a component includes retrieving measured health signatures from the component, retrieving component usage variables, estimating component health signatures using an aging model, determining an aging derivative using the aging model and calculating an aging error based on the estimated component health signatures, the aging derivative and the measured health signatures.

Abstract: A disc braking system of a vehicle determines the actual temperature of a brake rotor. The disc braking system compares the actual temperature of the brake rotor to a critical temperature of the brake rotor. The critical temperature of the brake rotor is a temperature above which damage and/or warping to the brake rotor may occur. The disc braking system applies a corrective measure to prevent damage to the brake rotor when the actual temperature of the brake rotor is greater than the critical temperature of the brake rotor. The corrective measure may include, but is not limited to: displaying a warning, adjusting a fraction control system of the vehicle, scheduling maintenance for the vehicle.

Abstract: A method for providing an estimate of brake pad thickness. The method employs fusion of sensors, if used, and driver brake modeling to predict the vehicle brake pad life. An algorithm is employed that uses various inputs, such as brake pad friction material properties, brake pad cooling rate, brake temperature, vehicle mass, road grade, weight distribution, brake pressure, brake energy, braking power, etc. to provide the estimation. The method calculates brake work using total work minus losses, such as aerodynamic drag resistance, engine braking and/or braking power as braking torque times velocity divided by rolling resistance to determine the brake rotor and lining temperature. The method then uses the brake temperature to determine the brake pad wear, where the wear is accumulated for each braking event. A brake pad sensor can be included to provide one or more indications of brake pad thickness from which the estimation can be revised.

Abstract: A system and method for telemetrically collecting on-road vehicle diagnostic data. In one embodiment, the method includes collecting vehicle diagnostic data from service shops, on-road vehicles and warranty records, aggregating the collected data and extracting knowledge therefrom. The extracted knowledge can be used to enhance algorithms on-board vehicles or at service centers so as to better identify vehicle faults and provide enhanced diagnostics and prognostics. The enhanced algorithms can then be used to provide predictive maintenance suggestions, provide trouble shooting assistance or provide vehicle design improvements.

Abstract: A system and method for providing proactive vehicle system management and maintenance using diagnostic and prognostic information. Vehicle information is collected from vehicle sensors and/or sub-systems by an on-board module on the vehicle and/or at a remote facility where the information is wirelessly transmitted to the remote facility. The collected information is analyzed to determine the health of various systems, sub-systems and components so that the remaining useful life of the systems, sub-systems and components can be predicted. By utilizing the diagnostic and prognostic information, a vehicle control strategy can be reconfigured to minimize customer impact. Further, if a software problem is detected, temporary or permanent software fixes can be provided automatically and remotely through a remote service garage.

Abstract: A system and method for determining the root cause of a fault in a vehicle system, sub-system or component using models and observations. In one embodiment, a hierarchical tree is employed to combine trouble or diagnostic codes from multiple sub-systems and components to get a confidence estimate of whether a certain diagnostic code is accurately giving an indication of problem with a particular sub-system or component. In another embodiment, a hierarchical diagnosis network is employed that relies on the theory of hierarchical information whereby at any level of the network only the required abstracted information is being used for decision making. In another embodiment, a graph-based diagnosis and prognosis system is employed that includes a plurality of nodes interconnected by information pathways. The nodes are fault diagnosis and fault prognosis nodes for components or sub-systems, and contain fault and state-of-health diagnosis and reasoning modules.

Abstract: A vehicle includes a plurality of sub-systems and corresponding controllers for effecting normal control thereover. The vehicle further includes a vehicle dynamics controller for providing high-priority sub-system commands for sub-system control to effect vehicle dynamics enhancements. The vehicle dynamics controller includes a plurality of independently decomposable and recomposable software components or layers and accessible inter-layer bus structure.

Abstract: A method for providing an estimate of brake pad thickness. The method employs fusion of sensors, if used, and driver brake modeling to predict the vehicle brake pad life. An algorithm is employed that uses various inputs, such as brake pad friction material properties, brake pad cooling rate, brake temperature, vehicle mass, road grade, weight distribution, brake pressure, brake energy, braking power, etc. to provide the estimation. The method calculates brake work using total work minus losses, such as aerodynamic drag resistance, engine braking and/or braking power as braking torque times velocity divided by rolling resistance to determine the brake rotor and lining temperature. The method then uses the brake temperature to determine the brake pad wear, where the wear is accumulated for each braking event. A brake pad sensor can be included to provide one or more indications of brake pad thickness from which the estimation can be revised.

Abstract: A system and method for reintegration of a redundant controller after occurrence of a fault is provided, comprising synchronizing outputs of a primary controller with outputs of secondary controllers. The controller is placed in a different mode of operation in which its output is not used in system control. A meta-controller is activated to drive the primary controller to the same states at which the secondary or redundant controllers operate. A voting mechanism is used to determine a fault in an output to a controlled device. Control of the device using the secondary outputs is effected. The primary controller recalculates the primary output, based upon the primary output; a feedback signal; and, the secondary outputs. Control using the primary output is permitted when the primary output is within an allowable range of the secondary outputs.

Abstract: A system and related method for monitoring the state of health of sensors in an integrated vehicle stability control system. In one embodiment, the system determines whether a yaw rate sensor, a lateral acceleration sensor or a hand-wheel angle sensor has failed. The system uses a plurality of models to generate estimates of the outputs of the sensors based on the actual sensor measurements. Residuals are generated as the difference between the measured value and each of the estimates for the particular sensor. The residuals are compared to a threshold to determine whether a fault flag will be set for each residual. The threshold for the hand-wheel angle sensor is an adaptive threshold because it does not have physical redundancy. If the fault flags for the residuals for each sensor have a particular pattern, then a fault is output for that sensor.

Abstract: A control system for warning a following vehicle of a potential collision with a leading vehicle. The leading vehicle includes a detection system for detecting the presence and velocity of the following vehicle. The control system determines a desired distance between the leading vehicle and the following vehicle based on the speed of the leading vehicle. The control system subtracts the desired distance from the actual distance to generate a distance error signal, and compares the distance error signal to a threshold. If the error signal is greater than the threshold, the control system may provide one or more operations, such as flashing hazard lights to warn the following vehicle, or taking other course of action in the event of an imminent collision, such as pre-tensioning seat belts and closing windows of the leading vehicle.

Abstract: A control system and method for use in vehicles, such as automotive vehicles. The control system and method is particularly adapted for use in vehicles having by-wire control systems. The control system uses three system controllers. Each of the controllers is adapted to receive redundant control inputs from at least one input device, such as a steering actuator, an accelerator actuator and a brake actuator. Each controller is adapted to receive a different unprocessed actuator sensor signal and a processed actuator sensor signal which are associated with the input device. Each controller may also be adapted to receive a sensor status signal which is also associated with the input device. In accordance with the method of the invention, these signals may be used to determine a sensor signal which may be used as the basis for control of control systems or components in response to the input device.

Abstract: A supervisory diagnostics system and related method for providing vehicle diagnostics for an integrated vehicle stability system that monitors the state of health of sensors, actuators, vehicle sub-system and communication sub-systems that are used in the stability control system. The diagnostics system employs an algorithm to determine whether the various sensors, actuators and sub-systems are operating properly. The algorithm determines whether the components and sub-systems are outputting valid signals at a component level. The algorithm also determines whether a bias of the sensors is below a predetermined limit. The algorithm further determines whether a comparison between the outputs of redundant sensors is below a predetermined threshold for a predetermined period of time. The system also performs a state of health analytical comparison of all the system signals. The system will go in to a fail-safe mode if a fault is detected.

Abstract: A system and method for providing state of health monitoring and fault diagnostics for a vehicle stability system. The system includes at least one primary sensor and at least one secondary sensor for sensing the operation of at least one vehicle characteristic. The system calculates an estimated output of the primary sensor using at least one estimate model, and generates at least one residual as the difference between a measured output of the primary sensor and the estimated output of the estimate model. The system uses a residual pattern to determine if the primary sensor is faulty. The system compares the measured output of the primary sensor to a measured output of the secondary sensor if the residual is less than a threshold, and determines that the secondary sensor is faulty if the comparison between the measured outputs of the primary and secondary sensors is greater than a predetermined threshold.