Various aspects of the present disclosure characterize apparatuses and/or methods as may be implemented with a variety of prosthetic components and applications. As may be consistent with one or more embodiments described herein, movement parameters pertaining to movement of a user of a prosthetic foot are sensed as the user travels along a surface, with the prosthetic foot having a front ball region and a rear heel region for respectively contacting the surface. A state of movement of the user, including a speed at which the user is travelling along the surface, is determined based on the sensed movement parameters. Utilizing a mechanical actuator, the prosthetic foot is dynamically positioned in response to the speed at which the user is travelling along the surface, by manipulating the mechanical actuator to move the rear heel region relative to the front ball region based on changes in the speed.

A prosthetic system includes a prosthetic foot defining an upper surface and having a flexible configuration and a pump system attached to the prosthetic foot. The pump system includes a pump mechanism defining a fluid chamber having variable configuration and an actuating part. The actuating part is arranged to selectively engage with and separate a distance from the upper surface of the foot plate to move the pump mechanism between a first position in which a volume of the fluid chamber is zero or near-zero and a second position in which the volume of the fluid chamber is expanded relative to the first position. The volume of the fluid chamber increases when the actuating part moves away from the upper surface of the foot plate.

A foot prosthesis that includes at least one spring element, an attachment member, and a heel member. The at least one spring element has a toe end portion, a heel end portion, an upper surface, and a lower surface. The attachment member is mounted to the upper surface and is configured to connect the foot prosthesis to a lower limb prosthesis component. A position of the attachment member is adjustable along a length of the at least one spring element. The heel member is mounted below the lower surface of the at least one spring element, and a position of the heel member is adjustable along the length of the at least one spring element.

Prosthetic feet that provide for variable and adjustable stiffness are provided. A foot element can include a tongue portion defined or formed by a slot in the foot element that at least partially separates the tongue portion from a remainder of the foot element. The tongue portion can be operably connected to the remainder of the foot member to increase the stiffness of the foot member or operably disconnected from the remainder of the foot member to increase the flexibility of the foot member. The prosthetic foot further includes a mechanism for adjusting whether the tongue portion is operably connected or disconnected from the remainder of the foot member. The mechanism can be selectively actuated to adjust the stiffness of the foot element in dorsiflexion and/or plantarflexion and/or to adjust the degree to which the tongue portion is allowed to flex relative to the remainder of the foot member.

A load bearing assistance apparatus for transferring load from a lower extremity orthotic or prosthetic device to the ground. The load bearing assistance apparatus includes a lateral and a medial spring-loaded members and a linking mechanism for connecting the load bearing assistance apparatus to the lower extremity orthotic or prosthetic device. The linking mechanism also connects the lateral and medial spring-loaded members in a spaced apart configuration so as to position them adjacent the lateral and medial portions, respectively, of the foot of the user of the lower extremity orthotic or prosthetic device and such that a portion of the lateral and medial spring-loaded members enters in contact with the ground during locomotion.

A vertical suspension system for a prosthetic foot includes a first member operatively coupleable to an amputee's residual leg. The suspension system can also include a second member coupleable to a prosthetic foot. One or more upper leaf springs and one or more lower leaf springs extend between and are attached to the first and second members such that at least one of the ends of each leaf spring is rotationally fixed to the first or second members, where the upper an lower leaf springs are spaced apart from each other.

A prosthetic foot comprising a vacuum system configured to attach to a vacuum attachment apparatus and a residual limb. The prosthetic foot may comprise a resilient bottom member, a resilient top member, and a vacuum system. The resilient bottom member may comprise a front end and a rear end. The resilient top member may comprise a front end and a rear end and the front end of the resilient top member may be connected to the front end of the resilient bottom member. The vacuum system may be coupled to an underside of the rear end of the top member. The vacuum system may comprise a compressible member, a chamber located within the compressible member, a valve system received within the compressible member, a passageway connecting the valve system and the chamber, and an air return coupled to the valve system and the vacuum attachment apparatus.

An actuator control system includes a motorized joint having first and second members rotatable relative to one another. An actuator is coupled with the motorized joint and is configured to rotate the first member relative to the second member in response to an input including a voltage, a current, or any combination thereof. A controller is coupled with the actuator and is configured to control the input using a control algorithm. The control algorithm controls the input based upon a mathematical model of biological muscle actuation that models titin as a filament which winds around actin during muscle actuation. In implementations the mathematical model includes mathematical representations of a contractile element, a viscous damping element in parallel with the contractile element, and a spring in series with the contractile element through a pulley and simultaneously in parallel with the contractile element.

In a powered actuator for supplying torque, joint equilibrium, and/or impedance to a joint, a motor is directly coupled to a low-reduction ratio transmission, e.g., a transmission having a gear ratio less than about 80 to 1. The motor has a low dissipation constant, e.g., less than about 50 W/(Nm).sup.2. The transmission is serially connected to an elastic element that is also coupled to the joint, thereby supplying torque, joint equilibrium, and/or impedance to the joint while minimizing the power consumption and/or acoustic noise of the actuator.

A device includes a first member and a second member disposed in series along a longitudinal axis. The device also includes links coupling first joints of the first member to second joints of the second member. The first and second members and the links arranged to define a planar parallelogram linkage. The devices also include a resilient element disposed between the first member and the second member, the first member and the second member preloaded against the resilient element. The first member and the second member are preloaded to provide an arrangement of the first and the second joints in which a motion of the first joints with respect to the second joints is constrained to a direction substantially parallel to the longitudinal axis. The devices further include a sensor for generating a signal indicating a separation between the first member and the second member.