Abstract: A system for controlling the rotational position of a solar collector trough includes a hydraulic cylinder having an output end and a linkage assembly. The linkage assembly includes at least one linkage member and a pair of pivot arms attached to the at least one linkage member. The pair of pivot arms is defined by a first pivot arm and a second pivot arm, each arm being pivotally attached to the at least one linkage member and the trough. The first and second pivot arms form respective parallel horizontal first and second pivot axes enabling the trough to be entirely movable over an angular range of motion extending over 180 degrees based totally on the linear movement of the output end of the hydraulic cylinder and in which an actuator control circuit controls the relative displacement of the cylinder output end.

Abstract: A system for controlling the rotational position of a solar collector trough includes a hydraulic cylinder having an output end and a linkage assembly. The linkage assembly includes at least one linkage member and a pair of pivot arms attached to the at least one linkage member. The pair of pivot arms is defined by a first pivot arm and a second pivot arm, each arm being pivotally attached to the at least one linkage member and the trough. The first and second pivot arms form respective parallel horizontal first and second pivot axes enabling the trough to be entirely movable over an angular range of motion extending over 180 degrees based totally on the linear movement of the output end of the hydraulic cylinder and in which an actuator control circuit controls the relative displacement of the cylinder output end.