Closed loop operation of a strength machine

Abstract

The systems and methods described herein provide an exercise machine that includes a closed loop control system to enhance or otherwise modify operations of the exercise machine. For example, the system may apply various closed loop control schemes based on data received from various sensors of the exercise machine, such as sensors with handles and/or motors of the exercise machine.

What is claimed is: 
     
         1 . An exercise machine, comprising:
 a platform that has a top surface upon which a user stands when performing a strength activity using the exercise machine,   a motor and a motor controller contained by the platform;   an attachment that is coupled to the motor; and   a closed loop control system that controls operation of the exercise machine based on information associated with a movement of the attachment and information associated with a rotation of the motor.   
     
     
         2 . The exercise machine of  claim 1 , wherein the attachment includes an inertial measurement unit (IMU) and the motor is associated with a torque sensor; and
 wherein the closed loop control system controls operation of the exercise machine based on a comparison of the data captured by the IMU and the torque sensor.   
     
     
         3 . The exercise machine of  claim 1 , wherein the attachment is coupled to the motor via a cable, and
 wherein the closed loop control system applies a control scheme to accelerate an inertia of the motor to align a movement of the cable with a movement of the attachment.   
     
     
         4 . The exercise machine of  claim 1 , wherein the closed loop control system controls operation of the exercise machine by:
 determining that a comparison of the information associated with the movement of the attachment to the information associated with the rotation of the motor indicates a cable that couples the attachment to the motor has slack; and   causing the motor controller to increase a torque applied to the cable by the motor.   
     
     
         5 . The exercise machine of  claim 1 , wherein the closed loop control system controls operation of the exercise machine by:
 determining that a comparison of the information associated with the movement of the attachment to the information associated with the rotation of the motor indicates the attachment is in a state of free fall; and   causing the motor controller to modify a torque applied to the cable by the motor.   
     
     
         6 . The exercise machine of  claim 1 , wherein the attachment is a handle held by the user when performing the strength activity using the exercise machine. 
     
     
         7 . The exercise machine of  claim 1 , wherein the attachment is coupled to the motor via a cable that extends from the motor to the attachment via an opening in the platform. 
     
     
         8 . The exercise machine of  claim 1 , further comprising:
 a servo coupled to the motor,   wherein the closed loop control system applies a control scheme to apply a load to the motor via the servo based on a comparison of the information associated with the movement of the attachment to the information associated with the rotation of the motor.   
     
     
         9 . A non-transitory computer-readable medium whose contents, when executed by a control system of a strength machine, causes the strength machine to perform a method of controlling operations of a resistance mechanism of the strength machine, the method comprising:
 capturing movement information associated with a handle of the strength machine by one or more inertial measurement units (IMUs) of the handle;   determining that the captured movement information indicates an abnormal movement of the handle with respect to a motor of the strength machine that is coupled to the handle via a cable; and   adjusting operation of the motor based on the determination.   
     
     
         10 . The non-transitory computer-readable medium of  claim 9 , wherein the abnormal movement of the handle includes a free fall movement of the handle. 
     
     
         11 . The non-transitory computer-readable medium of  claim 9 , wherein the abnormal movement of the handle includes an introduction of slack to the cable that couples the motor to the handle. 
     
     
         12 . The non-transitory computer-readable medium of  claim 9 , wherein the abnormal movement of the handle includes an acceleration of the handle that is different than an acceleration of the cable. 
     
     
         13 . The non-transitory computer-readable medium of  claim 9 , wherein adjusting operation of the motor based on the determination includes increasing a torque applied to the cable via the motor. 
     
     
         14 . The non-transitory computer-readable medium of  claim 9 , wherein adjusting operation of the motor based on the determination includes decreasing a torque applied to the cable via the motor. 
     
     
         15 . The non-transitory computer-readable medium of  claim 9 , wherein adjusting operation of the motor based on the determination includes modifying a load applied to the motor. 
     
     
         16 . The non-transitory computer-readable medium of  claim 9 , wherein determining that the captured movement information indicates an abnormal movement of the handle with respect to a motor of the strength machine that is coupled to the handle via a cable includes comparing the captured movement information to rotation information captured by a torque sensor of the motor. 
     
     
         17 . A method of controlling a motor of a strength machine, the method comprising:
 receiving information captured by a movement sensor of a handle of the strength machine;   receiving information captured by a torque sensor of a motor of the strength machine that is coupled to the handle;   comparing the information captured by a movement sensor of a handle to the information captured by a torque sensor of a motor; and   applying a closed loop control scheme to a current operation of the motor based on the comparison.   
     
     
         18 . The method of  claim 17 , wherein comparing the information captured by a movement sensor of a handle to the information captured by a torque sensor of a motor includes determining that a movement of the motor is misaligned with an expected movement of the handle. 
     
     
         19 . The method of  claim 17 , wherein comparing the information captured by a movement sensor of a handle to the information captured by a torque sensor of a motor includes determining that the handle is in a state of free fall. 
     
     
         20 . The method of  claim 17 , wherein the handle is coupled to the motor via a cable, and
 wherein applying a closed loop control scheme to a current operation of the motor based on the comparison includes modifying the current operation of the motor to reduce slack introduced to the cable via a movement of the handle.