Abstract: An electric drive system of a vehicle comprises a motor, a position sensor, an inverter, sensors to sense current and voltage supplied to the motor, and a controller to control the motor by controlling the inverter based on data from the position sensor and the sensors and a torque command. The controller estimates a motor torque using a motor model, calculates the motor torque, and generates a first state of health for the electric drive system based on a difference between the estimated and calculated motor torques. The controller generates, in response to the first state of health being less than or equal to a first threshold, a second state of health for at least one of the position sensor, the sensors, and the motor, and determines whether one of the position sensor, the sensors, and the motor is faulty based on the first and second states of health.

Abstract: A machine bearing disposed on a rotatable member, such as may be present on a vehicle, is described. A method for monitoring a state of health of the machine bearing includes monitoring, via a microphone, an acoustic signal, and coincidently determining a rotational speed of the rotatable member associated with the machine bearing. The sound spectrum is correlated to the rotational speed of the rotating member, and a time-frequency analysis is executed to determine a sound spectrum. The sound spectrum is transformed to a residual spectrum. A first feature associated with a first frequency band and a second feature associated with a second frequency band are extracted from the residual spectrum. The state of health associated with the machine bearing is detected based upon the first and second features, and is communicated to a second controller.

Abstract: An electric drive system of a vehicle comprises a motor, a position sensor, an inverter, sensors to sense current and voltage supplied to the motor, and a controller to control the motor by controlling the inverter based on data from the position sensor and the sensors and a torque command. The controller estimates a motor torque using a motor model, calculates the motor torque, and generates a first state of health for the electric drive system based on a difference between the estimated and calculated motor torques. The controller generates, in response to the first state of health being less than or equal to a first threshold, a second state of health for at least one of the position sensor, the sensors, and the motor, and determines whether one of the position sensor, the sensors, and the motor is faulty based on the first and second states of health.

Abstract: In various embodiments, methods, systems, and vehicles are provided for determining a fault in a suspension system of a vehicle. In an exemplary embodiment, sensor data is obtained via one or more vehicle sensors during operation of the vehicle; a one or more first coefficients for the vehicle are calculated via a processor using a pitch model with the sensor data; one or more second coefficients for the vehicle are calculated via the processor using a roll model with the sensor data; and a fault in the suspension system is determined via the processor using the first coefficients and the second coefficients.

Abstract: A machine bearing disposed on a rotatable member, such as may be present on a vehicle, is described. A method for monitoring a state of health of the machine bearing includes monitoring, via a microphone, an acoustic signal, and coincidently determining a rotational speed of the rotatable member associated with the machine bearing. The sound spectrum is correlated to the rotational speed of the rotating member, and a time-frequency analysis is executed to determine a sound spectrum. The sound spectrum is transformed to a residual spectrum. A first feature associated with a first frequency band and a second feature associated with a second frequency band are extracted from the residual spectrum. The state of health associated with the machine bearing is detected based upon the first and second features, and is communicated to a second controller.

Abstract: An apparatus and method that detect a condition of a vehicle component are provided. The method includes diagnosing vehicle health of a vehicle by analyzing one or more from among vehicle performance, vehicle energy usage, and vehicle vibration and acoustics, performing fault isolation on the vehicle to detect a health condition of a vehicle component corresponding to the isolated fault if the vehicle health below a predetermined threshold, monitoring the vehicle component corresponding to the isolated fault and estimating a remaining useful life of the vehicle component corresponding to the isolated fault, and performing one or more from among continuously monitoring, scheduling maintenance, providing a warning, and performing fault mitigation based on the estimated remaining useful life of the vehicle component corresponding to the isolated fault.

Abstract: An apparatus and method that detect a condition of a vehicle component are provided. The method includes diagnosing vehicle health of a vehicle by analyzing one or more from among vehicle performance, vehicle energy usage, and vehicle vibration and acoustics, performing fault isolation on the vehicle to detect a health condition of a vehicle component corresponding to the isolated fault if the vehicle health below a predetermined threshold, monitoring the vehicle component corresponding to the isolated fault and estimating a remaining useful life of the vehicle component corresponding to the isolated fault, and performing one or more from among continuously monitoring, scheduling maintenance, providing a warning, and performing fault mitigation based on the estimated remaining useful life of the vehicle component corresponding to the isolated fault.

Abstract: There is provided a method and article of manufacture for monitoring an electrical energy storage device for a system. The method comprises stabilizing the electrical energy storage device. Once the device is stabilized, a discrete electrical load is cyclically applied to the electrical energy storage device and state variables of the electrical energy storage device are monitored. A resistance of the electrical energy storage device is determined, and a remaining useful life parameter of the electrical energy storage device is determined based upon the determined resistance.

Abstract: A system and method for monitoring the state of health of sensors, actuators and sub-systems in an integrated vehicle control system. The method includes identifying a plurality of potential faults, identifying a plurality of measured values, and identifying a plurality of estimated values based on models in the control system. The method further includes identifying a plurality of residual error values as the difference between the estimated values and the measured values. The method also defines a plurality of fuzzy logic membership functions for each residual error value. A degree of membership value is determined for each residual error value based on the membership functions. The degree of membership values are then analyzed to determine whether a potential fault exists.

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 method for classifying a road surface condition by estimating the maximum tire/road surface coefficient of friction and actively inducing acceleration or deceleration. In one embodiment, the induced acceleration/deceleration is provided by applying torque to the driven wheels of the vehicle. The speeds of the driven and non-driven wheels are measured. The tire/road surface coefficient of friction and the driven wheel slip ratio are calculated from the wheel speeds. The tire/road surface coefficient of friction and the wheel slip ratio are used to determine the slope of the wheel slip/coefficient of friction curve, which is used to classify the road surface condition.

Abstract: A method and system providing coordinated torque control and speed control of a vehicle equipped with individual wheel motors, a steering system, and yaw-rate detection to achieve a desired yaw moment for the vehicle, based upon operator input and vehicle operation, is described. This includes determining a commanded steering angle, and a yaw-rate error, based upon the commanded steering angle and detected yaw-rate. A desired wheel motor yaw torque moment is calculated. First and second torque moments are calculated for inner and outer motored wheels, based upon the desired wheel motor yaw torque moment. First and second ideal wheel speeds are calculated for the inner and outer motored wheels, based upon the commanded steering angle. Torque and speed at each inner motored wheel and each outer motored wheel are calculated, based upon the yaw-rate error, the first and second torque moments, and the first and second ideal wheel speeds.

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.

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 predictive energy management system for a hybrid vehicle that uses certain vehicle information, such as present location, time, 3-D maps and driving history, to determine engine and motor power commands. The system forecasts a driving cycle profile and calculates a driver power demand for a series of N samples based on a predetermined length of time, adaptive learning, etc. The system generates the optimal engine and motor power commands for each N sample based on the minimization of a cost function under constraint equations. The constraint equations may include a battery charge power limit, a battery discharge power limit, whether the battery state of charge is less than a predetermined maximum value, whether the battery state of charge is greater than a predetermined minimum value, motor power output and engine performance. The system defines the cost function as the sum of the total weighted predicted fuel consumed for each sample.

Abstract: A system and method for determining a commanded engine and motor torque to minimize fuel consumption and manage battery state of charge in a hybrid electric vehicle. The method includes determining a penalty factor value that dictates the usage of the battery. A cost value is determined for every feasible engine torque for a selected or demanded vehicle torque and speed request. Each cost value is determined by a fuel consumption value, a change in the battery state of charge and the penalty factor value. The change in the battery state of charge is determined from the motor power and a nominal battery state of charge. For a specific penalty factor, a look-up table for optimal engine torque is generated for different requested vehicle torques at various vehicle speeds. A separate look-up table is provided for each penalty factor.

Abstract: A brake control system for brake by wire applications having a dual fail-silent pair controller architecture. The system utilizes two supervisory controllers and a shared monitoring controller to achieve the dual fail-silent pair configuration. The brake control system also features a mechanism whereby the monitoring controller ensures the fail-silent operation of the brake control units in the event of certain undesired events occurring within the system by assuming control of the affected brake control units. The control system further assures that no single event, including an event related to the monitoring controller, causes loss of more than half the braking functionality. The control system also features additional redundancy with regard to the brake command signals by sharing a separate unprocessed brake command signal with each of the supervisory controllers and the monitoring controller.

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.