Abstract: A method for vehicle stabilization includes, in response to a determination that a fault occurred in a rear steering mechanism, identifying a fault type associated with the fault. The method also includes determining whether a position of a rack of the rear steering mechanism is controllable based on the fault type. The method also includes, in response to a determination that the position of the rack is controllable, selectively positioning the rack to a center position and holding, using a motor control system of the rear steering mechanism, the rack in the center position. The method also includes, in response to a determination that the position of the rack is not controllable, holding, using the motor control system of the rear steering mechanism, the rack in a current position.

Abstract: A system for controlling a synchronous motor drive may be configured to receive a command voltage signal and to identify, in the synchronous motor drive, a resistance imbalance signature from the command voltage signal. The system may determine, based on the resistance imbalance signature, respective phase resistances that correspond to phases of a synchronous motor of the synchronous motor drive. Each respective phase resistance may include a phase transistor resistance and a phase winding resistance. The system may identify, based on the phase resistances and an estimated average resistance between the phases of the synchronous motor, one or more phases of the synchronous motor that correspond to one or more phase resistances representing a resistance imbalance.

Abstract: Technical features of a steering system include a control module that dynamically determines an operating mode based on a set of input signal values such as lateral acceleration signal values and corresponding handwheel position values. The control module dynamically determines and learns classification boundaries between multiple operating modes based the input signal values. The control module further calibrates the steering system according to operating mode that is determined using the classification boundaries.

Abstract: A system for controlling a synchronous motor drive may be configured to receive a command voltage signal and to identify, in the synchronous motor drive, a resistance imbalance signature from the command voltage signal. The system may determine, based on the resistance imbalance signature, respective phase resistances that correspond to phases of a synchronous motor of the synchronous motor drive. Each respective phase resistance may include a phase transistor resistance and a phase winding resistance. The system may identify, based on the phase resistances and an estimated average resistance between the phases of the synchronous motor, one or more phases of the synchronous motor that correspond to one or more phase resistances representing a resistance imbalance.

Abstract: A control system for monitoring operation of an electric motor includes a plurality of position sensors configured to measure a position of the electric motor, an indirect position estimation module configured to indirectly estimate the position of the motor, and an error monitoring module. The error monitoring module is configured to perform at least one of: comparing a measured position from the plurality of position sensors to an estimated position from the sensor position estimation module, and detecting a failure of at least one of the one or more position sensors based on the comparison; and calculating a difference between the measured position from one of the plurality of position sensors and the measured position from another of the plurality of position sensors, and causing the indirect position estimation module to initiate estimation of the position of the motor based on the difference.

Abstract: A method for vehicle stabilization includes, in response to a determination that a fault occurred in a rear steering mechanism, identifying a fault type associated with the fault. The method also includes determining whether a position of a rack of the rear steering mechanism is controllable based on the fault type. The method also includes, in response to a determination that the position of the rack is controllable, selectively positioning the rack to a center position and holding, using a motor control system of the rear steering mechanism, the rack in the center position. The method also includes, in response to a determination that the position of the rack is not controllable, holding, using the motor control system of the rear steering mechanism, the rack in a current position.

Abstract: Technical solutions are described for current sensor fault mitigation for systems with permanent magnet DC drives. An example power steering system includes a brush motor, and a motor control system that generates an amount of torque using the brush motor, the amount of torque corresponding to a torque command. The motor control system includes a current sensor fault detector that detects a current sensor fault associated with a current sensor used to measure a current across the brush motor. The motor control system further includes a velocity observer that computes an estimated motor velocity in response to the current sensor fault. The motor control system further includes a feedforward controller that generates a current command for generating the amount of torque using the brush motor, the current command generated using the estimated motor velocity.

Abstract: One or more embodiments are described for preventing controller windup in a motion control system. An example system includes a regulator that receives an input command to adjust a motion control variable of a mechanical system that includes a motor, the regulator configured to generate a first torque command based on the input command and an output torque from the motor. The system further includes a motor control module that receives the first torque command to generate an input torque command that is sent to the motor. The system further includes an anti-windup module that is configured to generate an anti-windup command based on the first torque command and the output torque, the anti-windup command being added to the input command that is sent to the regulator.

Abstract: Technical solutions are described for a motor control system to control a permanent magnet DC (PMDC) machine. An example motor control system includes one or more sensors for measuring an output current of the PMDC machine. The motor control system further includes a current regulator that generates a voltage command corresponding to an input current command for generating an amount of torque using the PMDC machine. The current regulator includes a current command compensator that generates a first voltage command based on the input current command received by the current regulator. The current regulator further includes a feedback compensator that generates a second voltage command based on the output current measured by the one or more sensors. The current regulator also includes an adder configured that generates the voltage command by adding the first voltage command and the second voltage command.

Abstract: Technical solutions are described for a motor control system to control a permanent magnet DC (PMDC) machine. An example motor control system includes one or more sensors for measuring an output current of the PMDC machine. The motor control system further includes a current regulator that generates a voltage command corresponding to an input current command for generating an amount of torque using the PMDC machine. The current regulator includes a current command compensator that generates a first voltage command based on the input current command received by the current regulator. The current regulator further includes a feedback compensator that generates a second voltage command based on the output current measured by the one or more sensors. The current regulator also includes an adder configured that generates the voltage command by adding the first voltage command and the second voltage command.

Abstract: One or more embodiments are described for preventing controller windup in a motion control system. An example system includes a regulator that receives an input command to adjust a motion control variable of a mechanical system that includes a motor, the regulator configured to generate a first torque command based on the input command and an output torque from the motor. The system further includes a motor control module that receives the first torque command to generate an input torque command that is sent to the motor. The system further includes an anti-windup module that is configured to generate an anti-windup command based on the first torque command and the output torque, the anti-windup command being added to the input command that is sent to the regulator.

Abstract: Technical solutions are described for a motor control system that includes a feedforward control module to control an output torque generated by the motor. The feedforward controlling includes computing a first voltage command for the motor based on an input torque signal. Further, the feedforward controlling includes computing a second voltage command for the motor based on a brush drop voltage of the motor and a back-EMF drop voltage of the motor. Further, feedforward controlling includes computing a voltage command for the motor by summing the first voltage command and the second voltage command. Further yet, the feedforward controlling includes sending the voltage command to the motor for generating the output torque.

Abstract: According to one or more embodiments, a biomechanical assistive device is described that generates and provide assist torque by detecting user intent. An example biomechanical assistive device includes a motor, and a controller that generates a torque command for providing assist torque using the motor based on a user activity being performed using the biomechanical assistive device. The controller determines a stride frequency based on a position signal indicative of a position of a joint of the biomechanical assistive device. The controller dynamically adjusts the torque command based on the stride frequency to generate a final torque command. The controller applies the final torque command to the motor.

Abstract: Technical solutions are described for current sensor fault mitigation for systems with permanent magnet DC drives. An example power steering system includes a brush motor, and a motor control system that generates an amount of torque using the brush motor, the amount of torque corresponding to a torque command. The motor control system includes a current sensor fault detector that detects a current sensor fault associated with a current sensor used to measure a current across the brush motor. The motor control system further includes a velocity observer that computes an estimated motor velocity in response to the current sensor fault. The motor control system further includes a feedforward controller that generates a current command for generating the amount of torque using the brush motor, the current command generated using the estimated motor velocity.

Abstract: Technical solutions are described for a motor control system that includes a feedforward control module to control an output torque generated by the motor. The feedforward controlling includes computing a first voltage command for the motor based on an input torque signal. Further, the feedforward controlling includes computing a second voltage command for the motor based on a brush drop voltage of the motor and a back-EMF drop voltage of the motor. Further, feedforward controlling includes computing a voltage command for the motor by summing the first voltage command and the second voltage command. Further yet, the feedforward controlling includes sending the voltage command to the motor for generating the output torque.

Abstract: Technical features of a steering system include a control module that dynamically determines an operating mode based on a set of input signal values such as lateral acceleration signal values and corresponding handwheel position values. The control module dynamically determines and learns classification boundaries between multiple operating modes based the input signal values. The control module further calibrates the steering system according to operating mode that is determined using the classification boundaries.

Abstract: A control system for monitoring operation of an electric motor includes a plurality of position sensors configured to measure a position of the electric motor, an indirect position estimation module configured to indirectly estimate the position of the motor, and an error monitoring module. The error monitoring module is configured to perform at least one of: comparing a measured position from the plurality of position sensors to an estimated position from the sensor position estimation module, and detecting a failure of at least one of the one or more position sensors based on the comparison; and calculating a difference between the measured position from one of the plurality of position sensors and the measured position from another of the plurality of position sensors, and causing the indirect position estimation module to initiate estimation of the position of the motor based on the difference.

Abstract: A system for estimating flux linkage in an electric motor includes a flux estimation module that generates estimated flux linkages based on a back electromagnetic force and estimated velocity of the electric motor, the flux linkages having an alpha flux linkage component and a beta flux linkage component, and a velocity estimation module that generates an estimated motor velocity based on the back electromagnetic force and the estimated flux linkages.

Abstract: An embodiment of a system for determining a sensor failure in a motor control system with at least three phase current measurements includes a magnitude computation module that determines a magnitude of a diagnostic voltage, the diagnostic voltage represented in a stator frame and based on a difference between an input voltage command and a final voltage command, and a phase evaluation module that determines a phase value of the diagnostic voltage based on the diagnostic voltage. The system also includes a sensor failure identification module that identifies a current sensor failure based on the phase value of the diagnostic voltage, the sensor failure represented by a failure signal, and a current calculation transition module that modifies a calculation scheme for determining a measurement of motor current based on the sensor failure.

Abstract: A system for estimating flux linkage in an electric motor includes a flux estimation module that generates estimated flux linkages based on a back electromagnetic force and estimated velocity of the electric motor, the flux linkages having an alpha flux linkage component and a beta flux linkage component, and a velocity estimation module that generates an estimated motor velocity based on the back electromagnetic force and the estimated flux linkages.