A solar energy system includes a photovoltaic (PV) assembly and a drive system. The PV assembly comprises a support subassembly and an array of PV panels pivotable therewith about a longitudinal axis of the PV assembly. The drive system comprises a motor assembly comprising an electric motor and a gearing arrangement, and a pivot wheel comprising a hoop-portion and joined to the PV assembly. The hoop portion includes an outer circumferential channel, and two opposing catches defining a maximum pivot range. A chain resides partly within the circumferential channel, is engaged with the two opposing catches, and is also in geared communication with the motor assembly such that the motor is operable to rotate the pivot wheel. In some embodiments, the opposing catches define a maximum pivot range through an arc of more than π radians and less than 2π radians.

A harmonic reducer includes a shaft having a first through hole extending from a first end to a second end of the shaft; a wave generator arranged on the shaft and being rotatable along with the shaft; a flexible spline arranged around the wave generator; a circular spline arranged around the flexible spline; a first flange coupled to the shaft via a first bearing and coupled to the flexible spline; and a second flange coupled to the shaft via a second bearing and coupled to the circular spline. One of the flanges is arranged near to the first end of the shaft. A cavity is provided between the one of the flanges and the first end of the shaft, such that it is in fluid communication with an external environment via the first through hole.

A pulley and a structure having the pulley connected with a driven unit are provided. The pulley includes a wheel portion and a lug portion. The wheel portion includes two circular end surfaces opposing each other and a side surface connecting the two end surfaces. The side surface includes a main arc face and a branch arc face. The branch arc face has a head end connected to the main arc face and a tail end configured to connect a strap. The branch arc face has a width in an axial direction of the wheel portion smaller than a width of the main arc face. The lug portion is fixed to the wheel portion, disposed at a position adjacent to the branch arc face along the width of the main arc face and extends to protrude beyond the branch arc face in a radial direction of the wheel portion.

In the present invention, dislodging of a belt is prevented even when there is slack in a fastening member that secures a movement-side pulley for adjusting an inter-axial distance. An adjustment mechanism that adjusts an inter-axial distance between a first pulley and a second pulley is provided with a support member to which the first pulley is provided, first and second long holes provided in an arm part body, first bolts that are inserted into the first long holes and that fasten the support member to the arm part body, and second bolts that are inserted into the second long holes and that fasten the support member to the arm part body. The first long holes have a first length that enables the support member to move toward the second pulley until the inter-axial distance reaches a distance at which the belt can be wound between the first and second pulleys. The second long holes have a second length that retains the inter-axial distance at a distance such that the state in which the belt is wound between the first and second pulleys is not dislodged.

A robot arm including a rotating body connected to a base, an arm rotating about a central axis of the rotating body, a moving pulley provided at the arm and revolving along a circular track which is concentric with the rotating body, a reference pulley provided at the base and positioned on an inner side with respect to the circular track, a spring embedded in the arm and compressed or stretched in a lengthwise direction of the arm, a string compressing the spring and wound around the moving pulley and the reference pulley, and a plurality of roller bearings arranged to be spaced apart from each other along an outer circumference of the rotating body, rotating about a rotation axis parallel to the central axis of the rotating body, and configured to be in contact with the string is provided.

A posture correction mechanism includes a carrier attached to a housing, and a gearwheel rotatably attached to the housing, the gearwheel includes a screw hole engaged with a screw which is moveable up and down relative to the housing for driving the gearwheel to rotate relative to the housing, two shafts are rotatably attached to the carrier and each has an arm rest, two gears are rotatably attached to the carrier and engaged with the gearwheel, the gears are connected to the shafts for allowing the shafts to be driven by the gearwheel to rotate relative to the carrier and for allowing the arm rests to be rotated toward or away from the user.

One embodiment provides a drive system that includes a drive device with at least one drum for spooling at least one wire rope. A mounting device is connected to the drive device and a single-axis tracker. At least one partial pulley is connected to a torque tube. The at least one partial pulley is configured to accept the at least one wire rope and to transfer leveraged drive forces to the torque tube.

A return device for retracting an attachment device of an aircraft. The attachment device is movable between a retracted storage position and a deployed working position, the return device tending to place the attachment device in the retracted storage position in the absence of an external load, while allowing the attachment device to move towards the deployed working position in the presence of an external load. The return device comprises resilient return means for exerting a traction return force on the attachment device and automatically bringing the attachment device into the retracted storage position; a force-reduction member for reducing the traction return force exerted by the resilient return means on the attachment device; and a line element having a first free end secured to the attachment device and a second free end secured to the force-reduction member.

A transmission apparatus for a leveraged wheelchair may include a wheelchair, a driving mechanism, a driving wheels set, and a transmission wheels set. The driving mechanism has a first tube and a second tube which are pivotally connected, and with the relative movements between the first tube and the second tube, the driving wheels set can have forward or rearward rotation so as to achieve bi-direction driving effect of the wheelchair. Also, the relative movement between the first tube and the second tube is cooperated with a flexible connecting head such that a handle of the wheelchair is adapted to be forward and rearward pulled or rotated axially so to achieve the moving and turning actions of the wheelchair with one hand.

A planar spring has an outer ring, an inner ring, and two elastic components. The inner ring is disposed in the outer ring, and forms a space therebetween. The two elastic components are disposed in the space, and are symmetric with respect to a central line at a spaced interval. Each elastic component has an outer connecting portion, an inner connecting portion, and a flexible strip. The outer connecting portion is connected to the outer ring at a first connecting point. The inner connecting portion is connected to the inner ring at a second connecting point. The flexible strip is connected between the outer connecting portion and the inner connecting portion. An included angle between the first connecting point and the second connecting point from the center is greater than or equal to 90 degrees and less than 180 degrees. A rotational series elastic actuator is also provided.