US Patent 10151966 Balanced camera slider

A camera slider has a base and a tubular hollow arm pivotally attached to the base. A counterweight carriage is supported on the arm on carriage rollers. An electric drive motor moves the counterweight carriage linearly on top of the arm. A slider counterweight is movable from a first position, wherein the counterweight carriage is at or adjacent to a first end of the arm and the slider counterweight is at or adjacent to a second end of the arm, and a second position wherein the counterweight carriage is at the second end of the arm, opposite from the first end, and the slider counterweight is at or adjacent to the first end of the arm.