System and method for motion-controlled foot unit

Abstract

A system and method associated with the movement of a limb. In one example, the system, such as a prosthetic or orthotic system, includes an actuator that actively controls, or adjusts, the angle between a foot unit and a lower limb member. A processing module may control movement of the actuator based on data obtained from a sensor module. For instance, sensing module data may include information relating to the gait of a user and may be used to adjust the foot unit to substantially mimic the movement of a natural, healthy ankle. The system may further accommodate, for example, level ground walking, traveling up/down stairs, traveling up/down sloped surfaces, and various other user movements. In addition, the processing module may receive user input or display output signals through an external interface. For example, the processing module may receive a heel height input from the user.

1 - 23 . (canceled) 
     
     
         24 . A method of controlling operation of a prosthetic ankle device comprising a foot unit and a lower limb member rotatably connected to each other about a pivot location, the method comprising:
 collecting data with one or more sensors located on the prosthetic ankle device while the prosthetic ankle device is connected either to a tibial stump of a transtibial amputee or to a separate prosthetic knee device worn by a transfemoral amputee, while a user of the prosthetic ankle device is moving;   processing data received from the one or more sensors to determine a current state of locomotion for the prosthetic ankle device; and   when the prosthetic ankle device is determined to be in a stance position, actuating an actuator to input a mechanical motion to rotate the foot unit relative to the lower limb member such that an angle between the foot unit and the lower limb member increases toward a plantarflexion position toward the end of the stance phase.   
     
     
         25 . The method of  claim 24 , further comprising, when the prosthetic ankle device is determined to be in the stance position, actuating the actuator to input a mechanical motion to rotate the foot unit relative to the lower limb member such that the angle between the foot unit and the lower limb member decreases toward a dorsiflexion position before increasing the angle toward a plantarflexion position. 
     
     
         26 . The method of  claim 24 , further comprising changing the angle between the foot unit and the lower limb member toward a dorsiflexion position at the beginning of swing phase after the angle is increased toward the end of stance phase. 
     
     
         27 . The method of  claim 24 , wherein the prosthetic ankle device comprises an attachment pyramid attaching the prosthetic ankle device either to the amputated stump of the transtibial amputee or to the separate prosthetic knee device at a location below the natural or artificial knee joint of the user. 
     
     
         28 . The method of  claim 27 , wherein the actuator is located below the attachment pyramid. 
     
     
         29 . The method of  claim 24 , wherein the actuator is located behind the lower limb member and is attached at a first end to an upper end of the lower limb member and at a second end to the foot unit behind the pivot location between the foot unit and the lower limb member. 
     
     
         30 . The method of  claim 24 , wherein the actuator comprises a motor that provides a pushing or pulling force to the foot unit with respect to the lower limb member to change the angle between the foot unit and the lower limb member. 
     
     
         31 . The method of  claim 24 , wherein the prosthetic ankle device is connected to a tibial stump of a transtibial amputee. 
     
     
         32 . The method of  claim 24 , wherein the prosthetic ankle device is connected to a separate prosthetic knee device of a transfemoral amputee. 
     
     
         33 . The method of  claim 32 , wherein the prosthetic ankle device is connected to a prosthetic knee comprising a second actuator separate from the actuator of the prosthetic ankle device. 
     
     
         34 . The method of  claim 24 , wherein the motor is powered by a battery located on the prosthetic ankle device. 
     
     
         35 . The method of  claim 24 , wherein the data is collected with one or more accelerometers. 
     
     
         36 . The method of  claim 24 , wherein the data is collected with one or more pressure sensors.