Abstract:
The control method for lower-limb assistive exoskeletons assists human movement by producing a desired dynamic response on the human leg. Wearing the exoskeleton replaces the leg's natural admittance with the equivalent admittance of the coupled system formed by the leg and the exoskeleton. The control goal is to make the leg obey an admittance model defined by target values of natural frequency, resonant peak magnitude and zero-frequency response. The control achieves these objectives objective via positive feedback of the leg's angular position and angular acceleration. The method achieves simultaneous performance and robust stability through a constrained optimization that maximizes the system's gain margins while ensuring the desired location of its dominant poles.
Abstract:
An apparatus for assisting the balance of a user is disclosed herein. The apparatus includes a first control moment gyroscope (CMG) and a second CMG configured as a scissor pair. The first CMG includes a first flywheel and a second flywheel, a first motor that rotates the first and second flywheels, a first gimbal supporting the first and second flywheel, and a first gimbal servo to rotate the first gimbal. The second CMG includes a third flywheel and a forth flywheel, a second motor that rotates the third and fourth flywheels, a second gimbal supporting the third and fourth flywheels, and a second gimbal servo to rotate the second gimbal. The apparatus additionally includes a gyroscope controller controlling the first gimbal servo and the second gimbal servo.
Abstract:
A method for stability control may include receiving vehicle characteristics of a vehicle of a vehicle-trailer system, trailer characteristics of a trailer of the vehicle-trailer system, or steering inputs for the vehicle. The method may include determining a prediction based on yaw rate deviation for the vehicle determined from the vehicle characteristics, trailer characteristics, or steering inputs or hitch rate oscillation of a hitch coupling the vehicle to the trailer determined from the vehicle characteristics, trailer characteristics, or steering inputs, where the prediction may be indicative of a likelihood of instability for the vehicle-trailer system. The method may include generating control actions based on the prediction and hitch rate feedback from the hitch of the vehicle-trailer system or lateral hitch force feedback.
Abstract:
The control method for lower-limb assistive exoskeletons assists human movement by producing a desired dynamic response on the human leg. Wearing the exoskeleton replaces the leg's natural admittance with the equivalent admittance of the coupled system formed by the leg and the exoskeleton. The control goal is to make the leg obey an admittance model defined by target values of natural frequency, resonant peak magnitude and zero-frequency response. The control achieves these objectives objective via positive feedback of the leg's angular position and angular acceleration. The method achieves simultaneous performance and robust stability through a constrained optimization that maximizes the system's gain margins while ensuring the desired location of its dominant poles.
Abstract:
A resistive exoskeleton control system has a controller generating a positive resistance by shaping a closed loop integral admittance of a coupled human exoskeleton system wherein a frequency response magnitude of the integral admittance is lower than that of a natural human joint for desired frequencies of interest and generating an assistance ratio of approximately zero for the desired frequencies of interest.
Abstract:
A jackknife warning condition controller and control method notifies a driver of a potential jackknife situation while backing up a vehicle with an attached trailer. The vehicle has a front axle with steerable front wheels controlled by the driver and a rear axle with non-steerable rear wheels. The trailer has a front axle with non-steerable front wheels and a rear axle with steerable rear wheels controlled by a trailer steering controller. The jackknife controller receives an operator-controlled vehicle steering angle and a measured hitch angle. The jackknife warning condition controller determines a directional jackknife warning condition and compares the measured hitch angle with the determined directional jackknife warning condition. If the measured hitch angle satisfies the directional jackknife warning condition then a notification is sent to the driver.
Abstract:
An apparatus for assisting the balance of a user is disclosed herein. The apparatus includes a first control moment gyroscope (CMG) and a second CMG configured as a scissor pair. The first CMG includes a first flywheel and a second flywheel, a first motor that rotates the first and second flywheels, a first gimbal supporting the first and second flywheel, and a first gimbal servo to rotate the first gimbal. The second CMG includes a third flywheel and a forth flywheel, a second motor that rotates the third and fourth flywheels, a second gimbal supporting the third and fourth flywheels, and a second gimbal servo to rotate the second gimbal. The apparatus additionally includes a gyroscope controller controlling the first gimbal servo and the second gimbal servo.
Abstract:
A robot controller controls a robot during a fall to reduce the damage to the robot upon impact. The robot controller causes the robot to achieve a tripod-like posture having three contact points (e.g., two hands and one foot) so that the robot motion in arrested with its center of mass (CoM) high above the ground. This prevents a large impact caused by the transfer of potential energy to kinetic energy during the fall. The optimal locations of the three contacts are learned through a machine learning algorithm.
Abstract:
An assistive exoskeleton control system has a controller generating a positive assistance by shaping a closed loop integral admittance of a coupled human exoskeleton system to a desired assistance ratio Ad by modifying a control transfer function using a cut-off frequency of a low pass filter.
Abstract:
A robot controller controls a robot during a fall to reduce the damage to the robot upon impact. The robot controller causes the robot to achieve a tripod-like posture having three contact points (e.g., two hands and one foot) so that the robot motion in arrested with its center of mass (CoM) high above the ground. This prevents a large impact caused by the transfer of potential energy to kinetic energy during the fall. The optimal locations of the three contacts are learned through a machine learning algorithm.