Abstract: A system for positioning a heliostat mirror or a solar collector includes a support structure, a pivot mechanism adapted to pivot the heliostat mirror or solar collector about a first generally horizontal axis and about a second axis generally perpendicular to the first axis, the pivot mechanism is attached to a rear side of the heliostat mirror or solar collector and attached to the support structure. The system also includes a first cable drive actuator having a first motor, driving a first cable spool, and a first cable attached at a proximal end to the first cable spool and attached at a distal end to the heliostat mirror or solar collector, and a second cable drive actuator having a second motor driving a second cable spool, and a second cable attached at a proximal end to the second cable spool and attached to the heliostat mirror or solar collector.

Abstract: An apparatus for capturing solar energy can include a solar energy capture device having an orientation plane and a sensor configured to determine a direction of gravity relative to a sensor plane. The solar energy capture device is configured to rotate about a pitch axis and a roll axis. The sensor plane can have an orientation that is fixed relative to the solar energy capture device. The orientation plane can he offset from the roll axis.

Abstract: The subject matter of this specification can be embodied in, among other things, a system that includes a reflective surface configured to reflect light to a target plane and three or more view ports that are optically connected to at least one camera, the view ports arranged in the target plane. A computing system is coupled to the camera and configured to receive image information captured by the view ports. The computing system, based on the image information and a relationship between intensity of light reflected by the reflective surface as captured by a particular view port and a distance of the particular view port to a point on the target plane that is a function of the light reflected from the reflective surface incident on or passing through the target plane, estimates a location on the target plane of the point.

Abstract: An apparatus for positioning an object, for example, a solar energy capture device, can include a frame, the object, a joint, and at least two linear actuators. The joint connects the object to the frame and allows the object to rotate relative to the frame. The first and second linear actuators are coupled to the object. When the first and second actuators are actuated in combination, the object rotates about a pitch axis. When the first and second actuators are actuated differentially, the object rotates about a roll axis.