Abstract: A photovoltaic system includes a collection of photovoltaic modules, a base supporting the collection of photovoltaic modules, and a damper coupled between the collection of photovoltaic modules and the base. The damper resists movement of the photovoltaic modules relative to the base. The damper has a first damping ratio when the collection of photovoltaic modules moves at a first rate relative to the base and a second damping ratio when the collection of photovoltaic modules moves at a second rate relative to the base, and the damper passively transitions from the first damping ratio to the second damping ratio.

Abstract: Damper includes a housing having proximal and distal ends, a first attachment point proximate the distal end of the housing, a rod having proximal and distal ends at least partially disposed within the housing and moveable relative to the housing between an extended position and a compressed position, a second attachment point proximate the proximal end of the rod, a piston joined to the rod within the housing proximate the distal end of the rod, the piston including a bypass groove having a flow area defined therein to allow fluid to flow from a first side of the piston to an opposing side of the piston, and a first washer disposed proximate a first end of the piston and at least partially covering the flow area of the bypass groove.

Abstract: PV modules and ballast arm assemblies are mounted onto a torque tube suspended from a support structure. The support structures allows torque tube, and mounted PV modules and ballast arm assemblies, to freely rotate. The ballast arm assembly includes a drive mechanism, an arm and a ballast. The drive mechanism allows the adjustment angle between the PV module and the arm and ballast to be changed. Changing the adjustment angle causes the torque tube, and mounted PV modules, to freely rotate to a different orientation angle in order to balance the moments of PV modules and ballast arm assemblies caused by gravity. The orientation angle can be changed throughout the day by changing the adjustment angle in order for the PV modules to track the sun.

Abstract: A wind load resistant, tracking photovoltaic solar array system may include a pivot support; at least one solar cell coupled to the pivot support; and a pivot arm coupled to the solar cell for providing transverse movement of the solar cell relative to a longitudinal axis of the pivot support. A transverse drive motor may be coupled to the pivot arm for rotating the pivot arm in response to control signals. A tube for housing the solar cell, pivot arm, and the transverse drive motor may also be included. A support structure may be coupled to the tube and for mounting the tube against another structure, such as a building rooftop. A longitudinal axis drive motor may be coupled to the tube and the support structure. The longitudinal axis drive motor may rotate the tube around a geometrical longitudinal axis of the tube in response to control signals.

Abstract: The invention relates to systems and methods for controlling angular position of a pivotable platform relative to a radiation source. In one embodiment, an apparatus for controlling angular position of a pivotable platform relative to a radiation source includes a frame, a thermal actuation element coupled to the frame, a pivotable platform positioned between the radiation source and the thermal actuation element so as to at least partially block energy from the radiation source from impinging on the thermal actuation element, and apparatus for pivoting the pivotable platform in response to a thermally controlled deformation of the thermal actuation element.