Abstract: A robotic manipulator comprises a plurality of spring compensated joints, each including a four-bar linkage mechanism, a gravity compensating spring, a spring adjustment mechanism, a spring adjustment actuator and an inertial actuator. The gravity compensating spring is coupled between two links of the four-bar linkage mechanism at two different spring attachment points to provide a lifting force opposing a gravitational load force. The spring adjustment mechanism is coupled to alter a position of one of the spring attachment points. The spring adjustment actuator is coupled to move the spring adjustment mechanism to alter the position of the spring attachment point and adjust the amount of lifting force provided by the spring. The inertial actuator is coupled between links of the four-bar linkage mechanism to effectuate rotational movement of the four-bar linkage mechanism and apply an adjustable amount of force to accelerate and manipulate a payload handled by the robotic manipulator.

Abstract: A robotic manipulator comprises a plurality of spring compensated joints, each including a four-bar linkage mechanism, a gravity compensating spring, a spring adjustment mechanism, a spring adjustment actuator and an inertial actuator. The gravity compensating spring is coupled between two links of the four-bar linkage mechanism at two different spring attachment points to provide a lifting force opposing a gravitational load force. The spring adjustment mechanism is coupled to alter a position of one of the spring attachment points. The spring adjustment actuator is coupled to move the spring adjustment mechanism to alter the position of the spring attachment point and adjust the amount of lifting force provided by the spring. The inertial actuator is coupled between links of the four-bar linkage mechanism to effectuate rotational movement of the four-bar linkage mechanism and apply an adjustable amount of force to accelerate and manipulate a payload handled by the robotic manipulator.

Abstract: An exoskeleton device in accordance with the present disclosure may generally include a series elastic actuator (SEA), a slider-crank mechanism and a four bar linkage mechanism. The SEA includes a motor and a ball screw coupled to a shaft of the motor via a shaft coupler, which transfers rotational motion of the shaft directly to the ball screw. The slider-crank mechanism includes a ball nut and a crank. As the ball screw rotates, the ball nut converts rotational motion of the ball screw into linear motion of the ball nut to drive the crank. The crank converts linear motion of the ball nut back into rotational motion at the input of the four bar linkage mechanism. The four bar linkage mechanism is coupled to an output of the crank and configured to provide a complex motion profile that emulates kinematics of a wearer's joint.

Abstract: A robotic manipulator comprises a plurality of spring compensated joints, each including a four-bar linkage mechanism, a gravity compensating spring, a spring adjustment mechanism, a spring adjustment actuator and an inertial actuator. The gravity compensating spring is coupled between two links of the four-bar linkage mechanism at two different spring attachment points to provide a lifting force opposing a gravitational load force. The spring adjustment mechanism is coupled to alter a position of one of the spring attachment points. The spring adjustment actuator is coupled to move the spring adjustment mechanism to alter the position of the spring attachment point and adjust the amount of lifting force provided by the spring. The inertial actuator is coupled between links of the four-bar linkage mechanism to effectuate rotational movement of the four-bar linkage mechanism and apply an adjustable amount of force to accelerate and manipulate a payload handled by the robotic manipulator.

Abstract: A robotic manipulator comprises a plurality of spring compensated joints, each including a four-bar linkage mechanism, a gravity compensating spring, a spring adjustment mechanism, a spring adjustment actuator and an inertial actuator. The gravity compensating spring is coupled between two links of the four-bar linkage mechanism at two different spring attachment points to provide a lifting force opposing a gravitational load force. The spring adjustment mechanism is coupled to alter a position of one of the spring attachment points. The spring adjustment actuator is coupled to move the spring adjustment mechanism to alter the position of the spring attachment point and adjust the amount of lifting force provided by the spring. The inertial actuator is coupled between links of the four-bar linkage mechanism to effectuate rotational movement of the four-bar linkage mechanism and apply an adjustable amount of force to accelerate and manipulate a payload handled by the robotic manipulator.

Abstract: A robotic manipulator comprises a plurality of spring compensated joints, each including a four-bar linkage mechanism, a gravity compensating spring, a spring adjustment mechanism, a spring adjustment actuator and an inertial actuator. The gravity compensating spring is coupled between two links of the four-bar linkage mechanism at two different spring attachment points to provide a lifting force opposing a gravitational load force. The spring adjustment mechanism is coupled to alter a position of one of the spring attachment points. The spring adjustment actuator is coupled to move the spring adjustment mechanism to alter the position of the spring attachment point and adjust the amount of lifting force provided by the spring. The inertial actuator is coupled between links of the four-bar linkage mechanism to effectuate rotational movement of the four-bar linkage mechanism and apply an adjustable amount of force to accelerate and manipulate a payload handled by the robotic manipulator.

Abstract: Embodiments of a series elastic actuator (SEA) disclosed herein include an elastic component coupled in series with a motor, wherein the elastic component comprises a pair of springs arranged concentrically around a central shaft of the housing for transmitting force to a mechanical ground of the SEA, and one or more spring support mechanisms arranged within an inner circumference of the springs. Some embodiments of the SEA may also include a spring deflection sensor, which is coupled within a recess formed within the mechanical ground of the SEA and configured to sense the force transmitted to the mechanical ground of the SEA.

Abstract: Embodiments of a series elastic actuator (SEA) disclosed herein include an elastic component coupled in series with a motor, wherein the elastic component comprises a pair of springs arranged concentrically around a central shaft of the housing for transmitting force to a mechanical ground of the SEA, and one or more spring support mechanisms arranged within an inner circumference of the springs. Some embodiments of the SEA may also include a spring deflection sensor, which is coupled within a recess formed within the mechanical ground of the SEA and configured to sense the force transmitted to the mechanical ground of the SEA.

Abstract: A robotic actuator may include a series elastic actuator (SEA) that includes an elastic element made of a viscoelastic material. The viscoelastic material may have hardness, stiffness, hysteresis, or damping properties suitable for a particular robotic application. The elastic element may include two portions of the viscoelastic material in compression with each other in the SEA. The SEA may include a motor to generate mechanical power, a speed reduction element to amplify motor torque, an encoder to measure deflection of the viscoelastic elastomer due to an applied force, and a transmission mechanism. The transmission mechanism may be connected to the motor using a pulley and may route mechanical power to an output joint. The SEA may be a prismatic SEA or another type of linear actuator. The motor may include a 3D printed liquid cooling jacket that includes removable fluid seals and that is assembled and disassembled using removable screws.

Abstract: A liquid-cooled motor may include a removable liquid cooling jacket. The jacket may enclose a commercial off-the-shelf electric motor. The jacket may be ribbed and may include multiple fluid channels, allowing fluid to circulate over the surface of the electric motor and limiting eddy currents. A front-most portion of the liquid-cooled motor may include electrical and fluid interfaces, including an inlet and an outlet for tubing to carry fluids. Removable gaskets or O-rings may be placed between the front-most portion and the jacket, and between a rear-most portion and the jacket. The jacket may be connected to the front-most portion and the rear-most portion using removable screws. The liquid-cooled motor may be disassembled for maintenance and then re-assembled. The jacket, front-most portion, and rear-most portion may be 3D printed from a watertight acrylic polymer, or machined from an engineering thermoplastic.