Patent ID: 7731670
Filing Date: 2010-06-08
Classification: A61H

Abstract:
1. A method for controlling an actuator of an exoskeleton with a controller, comprising: the controller receiving a desired mechanical impedance function of the exoskeleton, the desired mechanical impedance function comprising a desired relationship between forces applied to the exoskeleton and resulting angular velocities of the exoskeleton at various frequencies; the controller receiving a measured interaction force, wherein the measured interaction force represents an interaction between the exoskeleton and a limb segment of a user wearing the exoskeleton; and controlling a kinematic trajectory of the actuator with the controller based on the measured interaction force using impedance control to implement the desired mechanical impedance function of the exoskeleton, the desired mechanical impedance function of the exoskeleton being an active impedance function that causes the exoskeleton to be assistive to the user wearing the exoskeleton by reducing a muscle torque required to move the limb segment, the desired mechanical impedance function comprising a negative exoskeleton impedance component, wherein the negative exoskeleton impedance component is determined by estimating a limb impedance component of the limb segment of the user and by negatively scaling the estimated limb impedance component based on a degree of reduction of the muscle torque required to move the limb segment.