Inertia mitigation system

Abstract

In all applications of force, all components, internal or external, moving or otherwise, have inertia associated with their mass and geometry. The inertia of the components, internal or external, moving or otherwise, is detrimental to the precision and/or accuracy of the force being applied by and/or to the system, whether the force is applied internally or externally to the system. A motorbased system and/or a method involves mitigating and/or reducing force errors caused by the inertia of the components, internal or external to the system, moving or otherwise, in systems built for the application of force, the forces being internal or external to the system. This is achieved, in part, by addressing the inertial effects of components in the load-application path, including a motor and/or other force-generating devices, force transmitting elements, and carriers of force between a motor and those elements that contribute to force error due to inertial effects.

What is claimed is: 
     
         1 . An exercise machine, comprising:
 an electro-mechanical device powering the exercise machine that has sufficient dynamic response such that a user feels only the commanded force plus the minimized error determined by a minimum resistance setting for the machine and maximum acceleration for which the machine is used or specified to be used.   
     
     
         2 . The exercise machine of  claim 1 , further comprising:
 a pulley; and   a cable configured to be at least partially wound around the pulley and to be connected to the electro-mechanical device.   
     
     
         3 . The exercise machine of  claim 2 , further comprising:
 a grip, wherein a first end of the cable is connected to the electro-mechanical device and a second end of the cable is connected to the grip; and   an inertial measurement unit (IMU) provided in the grip and configured to measure specific force applied to the grip, angular rates of the grip and orientation of the grip.   
     
     
         4 . The exercise machine of  claim 3 , further comprising a hardware embedded processor configured to:
 receive the specific force of the grip, the angular rates of the grip and the orientation of the grip from the IMU via an electrical connection with the IMU, and   control the electro-mechanical device based on the specific force of the grip, the angular rates of the grip and the orientation of the grip to counteract inertia in the system by adjusting a torque outputted by the electro-mechanical device to provide a more linear feel to the user applying a force to the cable.   
     
     
         5 . The exercise machine of  claim 4 , wherein a mechanism is added to periodically reset the error that accumulates in a reported position and orientation of an IMU over time, such that the acceleration reported by the sensor remains sufficiently accurate over the course of an exercise session such that when the signal is used to compensate for system inertial effects, system force error remains below the additive sum of the minimum resistance setting and maximum intended force error of the system. 
     
     
         6 . An exercise machine, comprising:
 an electro-mechanical device powering the exercise machine that has sufficient dynamic response such that a user feels only the commanded force plus the minimized error determined by a minimum resistance setting for the machine and maximum acceleration for which the machine is used or specified to be used;   a frame;   an arm through which the cable passes;   a locking plate attached to the frame; and   a vertical locking mechanism configured to lock the arm relative to the locking plate.   
     
     
         7 . The exercise machine of  claim 6 , wherein the locking plate includes a plurality of teeth and is fixed to the frame, and
 wherein the vertical locking mechanism includes a locking tooth that engages a space between two adjacent teeth among the plurality of teeth to lock the arm vertically.   
     
     
         8 . The exercise machine of  claim 7 , wherein the locking plate teeth, voids, and locking tooth are not trapezoidal, such that engagement of the locking tooth on top of a sector tooth will be unstable and cause the locking tooth to slide into and engage a void, rather than a sector tooth. 
     
     
         9 . The exercise machine of  claim 7 , wherein the vertical locking mechanism further includes a spring connected to the locking tooth, the spring being configured to apply a preload to the locking tooth in order to minimize relative movement between the arm and the locking plate. 
     
     
         10 . An exercise machine, comprising:
 an electro-mechanical device powering the exercise machine that has sufficient dynamic response such that a user feels only the commanded force plus the minimized error determined by a minimum resistance setting for the machine and maximum acceleration for which the machine is used or specified to be used; and   a flat plate force sensor that is attached to a pulley over or under which a cable passes,   where said cable is at least part of the load path between the electro-mechanical device and physical user implement.