Abstract: A directional-control valve is typically comprised of a valve spool that slides linearly within a valve body. The valve body typically includes five internal ports, which are covered or exposed as the spool slides within the body. The typical five-internal-port architecture precludes certain combinations of port connectivity when the spool is in the center position. For example, when the spool is in the center position, providing connectivity between the actuator ports, while simultaneously providing fluid isolation of the supply and exhaust ports, is not directly achievable with a standard five-port architecture. This application describes three embodiments that enable the aforementioned port connectivity when the spool is in the center position.

Abstract: A circuit includes first and second current control sub-circuits connected in series between a DC supply voltage node and a reference voltage node and third and fourth current control sub-circuits connected in series between the DC supply voltage node and the reference voltage node. The circuit also includes a DC/DC converter with a first input terminal coupled to the first load node between the first and second current control sub-circuits, a second input terminal coupled to a second load node between the third and fourth current control sub-circuits, a first output terminal, and a second output terminal. The circuit further includes output electrodes, a routing sub-circuit for selectively coupling the output electrodes to the output terminals, and a controller configured for operating the routing sub-circuit and the current control sub-circuits to cause the DC/DC converter to supply biphasic pulses for at least one of the pairs of output electrodes.

Abstract: An orthotic device includes an upper arm section for receiving an upper portion of an arm of a subject, a forearm section for receiving a forearm section of the arm, and at least one elbow joint rotatably coupling the upper arm section and the forearm section. In the orthotic device, the forearm section includes a release control operatively coupled to the at least one elbow joint, where the release control is configured to transition the at least one elbow joint from a restricted motion state to a free motion state when the release control is activated.

Abstract: In one embodiment, the orthotic device can include a powered hand portion, a switching element, and a controller. The wearer can interact with the switching element to generate input signals for adjusting an operation of the powered hand portion. The controller can receive the input signals and generate control signals to accordingly adjust the operation of the powered hand portion. In some embodiments, a powered hand portion can be comprised of a plurality of linkages and at least one powered actuator to assist with an opening and closing of the hand portion. The plurality of linkages can be operated by at least one electric motor with quick-connect elements to link onto fingers of a user. In some embodiments, an electrically-actuated clutch mechanism can be affixed to an upper arm section and a lower arm section of an orthotic device. The clutch mechanism can be configured into different positions.

Abstract: Systems and methods for a running controller for a lower limb device including at least a powered knee joint are provided. The method includes collecting real-time sensor information for the lower limb device and configuring the lower limb device to a first state in a finite state model for an activity mode including the running mode. The method further includes, based on the sensor information, transitioning the lower limb device from a current state to a subsequent state in the finite state model for the detected mode when a pre-defined criteria for transitioning to the subsequent state is met, and repeating the transitioning until the activity mode changes. In the system and method, the finite state model includes at least one stance state and at least one swing state, where the at least one stance state includes at least one absorption state and at least one propulsion state.

Abstract: A powered leg prosthesis including a powered knee joint with a knee joint and a knee motor unit for delivering power to the knee joint, a powered ankle joint coupled to the knee joint including an ankle joint and an ankle motor unit to deliver power to the ankle joint, a prosthetic foot coupled to the ankle joint, a plurality of sensors for measuring a real-time input, and controller for controlling movement of the prosthesis based on the real-time input. In the powered leg prosthesis, at least one of the knee motor unit or the ankle motor unit includes at least one drive stage, where the drive stage includes a rotary element for generating torque and at least one looped element affixed around the rotary element and configured for transmitting the torque to another rotary element coupled to a joint to be actuated.

Abstract: An orthotic device includes an upper arm section for receiving an upper portion of an arm of a subject, a forearm section for receiving a forearm section of the arm, and at least one elbow joint rotatably coupling the upper arm section and the forearm section. In the orthotic device, the forearm section includes a release control operatively coupled to the at least one elbow joint, where the release control is configured to transition the at least one elbow joint from a restricted motion state to a free motion state when the release control is activated.

Abstract: A neural processing unit (NPU) is described. The NPU includes an NPU direct memory access (NDMA) core. The NDMA core includes a read engine having a read buffer. The NDMA core also includes a write engine having a write buffer. The NPU also includes a controller. The controller is configured to direct the NDMA core to perform hardware pre-processing of NDMA data in the read buffer and post-processing of NDMA data in the write buffer on blocks of a data stripe to process tensors in artificial neural networks.

Abstract: A method of exploiting activation sparsity in deep neural networks is described. The method includes retrieving an activation tensor and a weight tensor where the activation tensor is a sparse activation tensor. The method also includes generating a compressed activation tensor comprising non-zero activations of the activation tensor, where the compressed activation tensor has fewer columns than the activation tensor. The method further includes processing the compressed activation tensor and the weight tensor to generate an output tensor.

Abstract: The present disclosure provides a method of accessing data from a first memory. The method may include receiving a command for accessing a first portion of the data. The data includes a plurality of words arranged as a multi-dimensional array of words that is stored contiguously in the first memory. The method may further include mapping the first portion of the data to a first portion of the plurality of words. The first portion of the plurality of words is not stored contiguously in the first memory. The method may further include accessing the first portion of the plurality of words while refraining from accessing at least a second portion of the plurality of words that is contiguously stored between at least two words of the first portion of the plurality of words.

Abstract: A neural processing unit (NPU) is described. The NPU includes an NPU direct memory access (NDMA) core. The NDMA core includes a read engine having a read buffer. The NDMA core also includes a write engine having a write buffer. The NPU also includes a controller. The controller is configured to direct the NDMA core to perform hardware memory bandwidth optimization for reading/writing NDMA data in the read buffer and/or NDMA data in the write buffer. The NDMA core is also configured to transparently combine NDMA transaction requests for a data stripe to increase local access to available tensors in artificial neural networks.

Abstract: A method of controlling a mobility device and related device including at least one actuator component that drives at least one joint component is described. The control method may include executing a control application with an electronic controller to perform: receiving a command in the control system of the mobility device for initiating an automated assessment and adjustment protocol; controlling one or more mobility device components to perform the automated assessment; electronically gathering user performance data associated with the automated assessment and determining user performance metrics; and electronically controlling one or more of the mobility device components in accordance with the performance metrics. The automated assessment includes controlling mobility device components to perform a predetermined assessment activity related to performance of the mobility device and/or user.

Abstract: Systems and methods for controlling a weight bearing member having at least one powered joint are provided. A system includes a velocity reference module for receiving myoelectric control signals from a user during a non-weight bearing mode for the powered joint and generating a velocity reference for the powered joint based on the myoelectric control signals. The system further includes a volitional impedance module for generating a torque control signal for actuating the powered joint based at least on the velocity reference.

Abstract: Systems and methods of operating a lower limb device having at least a powered joint are provided. A method includes configuring the device to a first state in a finite state model for a current activity mode including a stair ascent mode or a stair descent mode. The method also includes, based on real-time sensor information, transitioning the device between different states in the finite state model when pre-defined criteria for transitioning among the different states are met. In the method, the finite state model for stair ascent includes lifting and swing phases, where the lifting phase includes a powered knee extension and a powered ankle push-off. The finite state model for stair descent includes yielding and swing states, where the swing states include providing a powered plantarflexion of the powered ankle joint and the yielding states include providing a resistive and passive plantarflexion of the powered ankle joint.

Abstract: Systems and methods for a running controller for a lower limb device including at least a powered knee joint are provided. The method includes collecting real-time sensor information for the lower limb device and configuring the lower limb device to a first state in a finite state model for an activity mode including the running mode. The method further includes, based on the sensor information, transitioning the lower limb device from a current state to a subsequent state in the finite state model for the detected mode when a pre-defined criteria for transitioning to the subsequent state is met, and repeating the transitioning until the activity mode changes. In the system and method, the finite state model includes at least one stance state and at least one swing state, where the at least one stance state includes at least one absorption state and at least one propulsion state.

Abstract: An asymmetric linear actuator is provided which integrates a hydraulic dissipater and an electric motor and power screw which generates small forces. The actuator is configured so that an electric motor drives a power screw which drives a rod through a cylinder to provide linear actuation. The cylinder is fluid-filled and incorporates a piston that separates the cylinder into a first and second fluid chamber which are filled with a first and second volume of working fluid. Movement of the piston and rod assembly results in fluid movement between the first and second volumes of working fluid and through the fluidic restriction. The fluidic restriction can be proportionally controllable via an electric motor which enables controllable power dissipation via control of the fluidic restriction motor and controllable power generation via control of the power screw motor.

Abstract: An apparatus for optimizing a computational network is configure to receive an input at a first processing component. The first processing component may include at least a first programmable processing component and a second programmable processing component. The first programmable processing component is configured to compute a first nonlinear function and the second programmable processing component is configured to compute a second nonlinear function which is different than the second nonlinear function. The computational network which may be a recurrent neural network such as a long short-term memory may be operated to generate an inference based at least in part on outputs of the first programmable processing component and the second programmable processing component.

Abstract: Systems and methods of operating a lower limb device having at least a powered joint are provided. A method includes configuring the device to a first state in a finite state model for a current activity mode including a stair ascent mode or a stair descent mode. The method also includes, based on real-time sensor information, transitioning the device between different states in the finite state model when pre-defined criteria for transitioning among the different states are met. In the method, the finite state model for stair ascent includes lifting and swing phases, where the lifting phase includes a powered knee extension and a powered ankle push-off. The finite state model for stair descent includes yielding and swing states, where the swing states include providing a powered plantarflexion of the powered ankle joint and the yielding states include providing a resistive and passive plantarflexion of the powered ankle joint.

Abstract: A jointed mechanical device is provided. The device includes at least one element having a fixed end and a deflectable end. The device also includes at least one actuating structure having a first end coupled to at least the deflectable end of the element, where the actuating structure includes at least one elastic element in series with at least one non-elastic element. The device further includes at least one force actuator configured to apply an actuator force to a second end of the actuating structure. Additionally, the device includes a control system for adjusting an operation of the force actuator based at least one actuation input, an amount of the actuator force, and an amount of displacement generated by the force actuator.

Abstract: 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.