Actively Controlled Exercise Device

Abstract

An actively controlled exercise device provides a dynamic force responsive workout. The device includes: a user output arm movably attached to a base frame; an actuator attached between the user output arm and the base frame, the actuator including a motor and an output shaft connected to the user output arm; at least one position sensor attached to the actively controlled exercise device adjacent to the user output arm for detecting a position and velocity of the output arm; a load cell attached to the actively controlled exercise device adjacent to the actuator for detecting a force exerted on the user output arm; and a force controller in communication with the position sensor, the load cell, and the actuator for activating the actuator to impart a force on the user output arm during an exercise repetition.

What is claimed is: 
     
         1 . An actively controlled exercise device comprising:
 a user output arm movably attached to a base frame and movable in at least a first exercise direction and a second exercise direction, wherein the first exercise direction corresponds to concentric work of a muscle of the user and the second exercise direction corresponds to eccentric work of the muscle of the user;   an actuator attached between the user output arm and the base frame, the actuator including a motor and an output shaft connected to the user output arm;   at least one position sensor attached to the actively controlled exercise device adjacent to the user output arm for detecting a position and velocity of the output arm;   a load cell attached to the actively controlled exercise device adjacent to the actuator for detecting a force exerted on the user output arm; and   a force controller in communication with the position sensor, the load cell, and the actuator for receiving data from the at least one sensor attached on the actively controlled exercise device and, in response to position, velocity, and force data received from the position sensor and load cell, activating the actuator to impart a force on the user output arm during an exercise repetition.   
     
     
         2 . The actively controlled exercise device of  claim 1 , wherein the actuator comprises a linear actuator. 
     
     
         3 . The actively controlled exercise device of  claim 2 , wherein the actuator comprises a ball screw linear actuator. 
     
     
         4 . The actively controlled exercise device of  claim 1 , comprising both at least one encoder sensor and one force sensor, wherein the force controller activates the actuator based on data detected by both the force sensor and encoder sensor. 
     
     
         5 . The actively controlled exercise device of  claim 1  wherein the position sensor comprises an absolute position encoder. 
     
     
         6 . The actively controlled exercise device of  claim 1 , wherein the force controller instructs the actuator to impart a force in the second eccentric work direction that is greater than the force imparted on the first concentric work direction. 
     
     
         7 . The actively controlled exercise device of  claim 1 , wherein the force controller activates the actuator to impart a ramped force on the user output arm such that the force is at a minimum when velocity is detected as zero and gradually increases when velocity is detected as being greater or less than zero. 
     
     
         8 . The actively controlled exercise device of  claim 1 , wherein the force controller activates the actuator to impart a positive force when the position sensor detects the user output arm to be at a first position, and wherein the force controller activates the actuator to impart a negative force when the position sensor detects the user output arm to be at a second position. 
     
     
         9 . The actively controlled exercise device of  claim 1 , wherein the force controller activates the actuator to move the user control arm along a fixed position and time path, and wherein data related to a force of the user on the user control arm is detected by the load cell adjacent to the actuator. 
     
     
         10 . The actively controlled exercise device of  claim 1 , wherein the force controller imparts a short perturbance force on the actuator during an exercise and detects a position and velocity response of the user through the user output arm. 
     
     
         11 . An actively controlled exercise device comprising:
 a user output arm movably attached to a base frame and movable in at least a first exercise direction and a second exercise direction, wherein the first exercise direction corresponds to concentric work of a muscle of the user and the second exercise direction corresponds to eccentric work of the muscle of the user;   an actuator attached between the user output arm and the base frame, the actuator including a motor and an output shaft connected to the user output arm;   at least one position sensor attached to the actively controlled exercise device adjacent to the user output arm for detecting a position and velocity of the output arm;   a load cell attached to the actively controlled exercise device adjacent to the actuator for detecting a force exerted on the user output arm; and   a force controller comprising a processor and computer readable storage and in electronic communication with the actuator, position sensor, and load cell, the force controller including one or more instructions executable on the processor for:
 detecting position, velocity, and force data from the position sensor and load cell; 
 in response to detected position, velocity, and force data, activating the actuator to impart a force on the user control arm; and 
 adjusting a force imparted on the user control arm based on one of a detected position, force, and velocity of the user control arm. 
   
     
     
         12 . A method of actively controlling an exercise device, the method comprising:
 providing a user output arm movable in relation to a base frame;   providing at least one encoder sensor and force sensor in communication with the user output arm for detecting a position and velocity of the user output arm and a force imparted on the user output arm;   providing an actuator in mechanical communication with the user output arm;   providing a force controller in electrical communication with the encoder sensor, force sensor, and actuator;   detecting a position and velocity of the user output arm with the encoder sensor;   detecting a force exerted on the user output arm by a user with the force sensor;   activating the actuator to impart a force on the user control arm based on a detected position, velocity, and force of the user control arm, wherein the force is greater when the user control arm is determined to be moving in an eccentric work direction and less when the user control arm is determined to be moving in a concentric work direction.