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 prosthetic foot system comprising:
 a prosthetic foot;   a lower limb member operatively coupled to the prosthetic foot and configured to pivot relative to the prosthetic foot; and   a power source configured to power rotation of the lower limb member relative to the prosthetic foot, wherein said rotation adjusts an angle between the lower limb member and the prosthetic foot;   wherein during a swing phase of the prosthetic foot during ambulation by a user on a ground surface, the prosthetic foot is configured to rotate relative to the lower limb member substantially mimicking the movement of a healthy ankle such that the angle between the lower limb member and the prosthetic foot first decreases to a dorsiflexed position and then increases to a plantarflexed position before contacting the ground surface with the prosthetic foot.   
     
     
         25 . The system of  claim 24 , wherein the prosthetic foot system is configured to exert a proportional response to the weight or impact levels on the prosthetic foot. 
     
     
         26 . The system of  claim 24 , wherein the weight of the user is used in the rotation of the lower limb member relative to the prosthetic foot. 
     
     
         27 . The system of  claim 24 , further comprising a device that selectively dampens the rotation of the prosthetic foot. 
     
     
         28 . The system of  claim 27 , wherein the device comprises a hydraulic damper. 
     
     
         29 . The system of  claim 24 , further comprising a spring to affect the rotation of the prosthetic foot. 
     
     
         30 . The system of  claim 24 , further comprising a linear actuator powered by the power source to cause the rotation of the prosthetic foot. 
     
     
         31 . The system of  claim 24 , further comprising:
 at least one sensor configured to monitor motion of at least one of the prosthetic foot and the attachment lower limb member; and   at least one processing module configured to receive data from the sensor regarding the monitored motion and to affect the rotation of the prosthetic foot during the swing phase in response to the monitored motion.   
     
     
         32 . The system of  claim 31 , wherein the at least one sensor comprises an accelerometer. 
     
     
         33 . The system of  claim 24 , further comprising an attachment portion, wherein the attachment portion is configured to facilitate coupling of the lower limb member to a user. 
     
     
         34 . A method for controlling a prosthetic ankle device, the method comprising:
 measuring, with at least one sensor, at least one variable relating to at least one of position and movement of a prosthetic ankle device, wherein the prosthetic ankle device comprises a foot unit and a lower limb member pivotally attached and configured to move relative to the foot unit;   generating data indicative of the at least one of position and movement of the prosthetic ankle device;   processing the data with a processing module to determine a gait pattern, event or position; and   adjusting the prosthetic ankle device based on the determined gait pattern, event or position to substantially mimic the movement of a healthy ankle, wherein said adjusting comprises causing a change in an angle between the foot unit and the lower limb member, and wherein during a swing phase, said adjusting causes first a decrease the angle to a dorsiflexion position and then an increase in the angle to a plantarflexion position.   
     
     
         35 . The method of  claim 34 , wherein the at least one sensor comprises at least one accelerometer. 
     
     
         36 . The method of  claim 34 , wherein the at least one sensor comprises at least one angular sensor. 
     
     
         37 . The method of  claim 34 , wherein the prosthetic ankle device is powered. 
     
     
         38 . The method of  claim 34 , wherein measuring the at least variable relating to at least one of position and movement of the prosthetic ankle device comprises measuring acceleration of the prosthetic ankle device in multiple, substantially, mutually perpendicular axes. 
     
     
         39 . The method of  claim 34 , wherein the data indicative of the at least one of position and movement of the prosthetic ankle device is used to determine at least one of the following: a position of the prosthetic ankle device with respect to ground; an inclination angle of the prosthetic ankle device; a direction of gravity with respect to a position of the prosthetic ankle device; information that relates to a stride of a user of the prosthetic ankle device; information that relates to when the prosthetic ankle device contacts ground at heel strike; information that relates to when the prosthetic ankle device is in mid-stride; information that relates to when the prosthetic ankle device leaves the ground at toe-off; a distance of the prosthetic ankle device from ground at a peak of a swing phase; and a timing of a peak of a swing phase. 
     
     
         40 . The method of  claim 34 , wherein the at least one sensor comprises at least one of a kinematic sensor, a single-axis gyroscope, a load sensor, a flex sensor, a myoelectric sensor, an accelerometer, and an angular sensor. 
     
     
         41 . The method of  claim 34 , further comprising determining with the at least one sensor an angle of the ground surface. 
     
     
         42 . The method of  claim 34 , wherein said processing comprises accessing data in memory indicative of a gait cycle phase of a user. 
     
     
         43 . A method for controlling a prosthetic ankle device, the method comprising:
 monitoring, with at least one sensor, at least one variable relating to at least one of position and movement of a prosthetic ankle device throughout at least one gait cycle, wherein the device comprises a foot unit and a lower limb member operatively coupled to the foot unit and configured to pivot relative to the foot unit;   generating data indicative of the at least one of position and movement throughout the at least one gait cycle;   processing the data with a processing module to determine a current gait pattern, event, or position;   determining ankle-angle adjustments corresponding to a determined gait pattern, event, or position; and   adjusting the device based on the determined ankle-angle adjustments corresponding to the determined gait pattern, event, or position, said ankle-angle adjustments being applied over a swing phase of subsequent gait cycles in accordance with the determined gait pattern, event, or position.   
     
     
         44 . The method of  claim 43 , wherein the adjusting comprises adjusting a resistance to rotation of the prosthetic ankle device. 
     
     
         45 . The method of  claim 43 , wherein the adjusting comprises adjusting a damping of the movement of the prosthetic ankle device. 
     
     
         46 . The method of  claim 43 , wherein the at least one sensor is located on the device. 
     
     
         47 . The method of  claim 43 , wherein the prosthetic ankle device comprises at least one active actuator, and the adjusting is at least partially done by the actuator. 
     
     
         48 . The method of  claim 43 , additionally comprising receiving and processing data indicative of at least one terrain variable and adjusting the device also based on the terrain variable. 
     
     
         49 . The method of  claim 48 , wherein the terrain variable is at least indicative of a slope of the ground surface. 
     
     
         50 . The method of  claim 43 , wherein the at least one sensor comprises at least one accelerometer. 
     
     
         51 . The method of  claim 43 , wherein the at least one sensor comprises at least one angular sensor. 
     
     
         52 . The method of  claim 43 , wherein a gait cycle comprises one full stride of a user. 
     
     
         53 . A prosthetic foot system comprising:
 a prosthetic foot;   a lower limb member operatively coupled to the prosthetic foot and configured to pivot relative to the prosthetic foot;   a power source configured to power rotation of the lower limb member relative to the prosthetic foot, wherein said rotation adjusts an angle between the lower limb member and the prosthetic foot; and   an actuator powered by the power source to affect the rotation of the lower limb member relative to the prosthetic foot, the actuator generally disposed at a location corresponding to the location of a human ankle;   wherein during a stance phase of the prosthetic foot during ambulation by a user on a ground surface, the prosthetic foot is configured to rotate relative to the lower limb member such that the angle between the lower limb member and the prosthetic foot first decreases to a dorsiflexed position and then increases to a plantarflexed position toward the end of the stance phase.   
     
     
         54 . The system of  claim 53 , wherein the actuator is a linear actuator. 
     
     
         55 . The system of  claim 53 , further comprising a spring to affect the rotation of the prosthetic foot. 
     
     
         56 . The system of  claim 53 , further comprising:
 at least one sensor configured to monitor motion of at least one of the prosthetic foot and the lower limb member; and   at least one processing module configured to receive data from the sensor regarding the monitored motion and to affect the rotation of the prosthetic foot in response to the monitored motion.   
     
     
         57 . The system of  claim 56 , wherein the at least one sensor comprises an accelerometer. 
     
     
         58 . The system of  claim 56 , wherein the at least one sensor comprises an angular sensor configured to determine an angle of a ground surface that the prosthetic foot operatively contacts. 
     
     
         59 . The system of  claim 53 , wherein the actuator is situated in a posterior position with respect to the lower limb member. 
     
     
         60 . A prosthetic foot system comprising:
 a prosthetic foot;   a lower limb member operatively coupled to the prosthetic foot and configured to pivot relative to the prosthetic foot;   an actuator operatively coupled to the prosthetic foot and the lower limb member, the actuator configured to affect an angle between the lower limb member and the prosthetic foot;   at least one sensor configured to monitor motion of at least one of the prosthetic foot and the lower limb member, the at least one sensor comprising a gyroscope; and   at least one processing module configured to receive data from the at least one sensor regarding the monitored motion and to affect the angle between the lower limb member and the prosthetic foot via at least the actuator in response to the monitored motion,   wherein during a stance phase of the prosthetic foot during ambulation by a user on a ground surface, the prosthetic foot is configured to rotate relative to the lower limb member such that the angle between the lower limb member and the prosthetic foot first decreases to a dorsiflexed position and then increases to a plantarflexed position toward the end of the stance phase.   
     
     
         61 . The system of  claim 60 , wherein the actuator comprises a linear actuator. 
     
     
         62 . The system of  claim 60 , wherein the at least one sensor further comprises an accelerometer. 
     
     
         63 . The system of  claim 60 , wherein the actuator is generally disposed at a location corresponding to the location of a human ankle. 
     
     
         64 . The system of  claim 60 , wherein the actuator comprises a spring. 
     
     
         65 . The system of  claim 60 , further comprising a power source configured to power the actuator.