Mechanisms for converting rotational motion into other types of motion, in particular uniform translational motion, are disclosed, and can be used as an oscillation compensator for stepping wheel propulsion units. An oscillation compensating device for a stepping wheel propulsion unit including supports fastened symmetrically to an output shaft that is fastened for transverse motion is actuated by an input shaft, the output shaft being fastened on the free end of a crank. The output shaft is set into rotation via a variator, which varies the angular velocity of the output shaft according to the current position of the crank and the angular velocity thereof. The need for cam mechanisms and springs in the device can be obviated, the coefficient of friction and the dimensions of the device can be reduced, and both spatial and speed oscillations can be significantly reduced.

A fully-electric grabber assembly includes a first grabber arm, a second grabber arm, an electric motor, and a plurality of gears. The plurality of gears includes a first gear coupled with the electric motor, an intermediate gear coupled with the first gear, and an arm gear coupled with the first grabber arm and the intermediate gear to facilitate pivoting the first grabber arm. The first gear is configured to rotate about an axis radially offset from a center thereof.

A linear actuator includes a support structure having a first face, and a second face opposite the first face; a first rack secured to the first face; a second rack secured to the second face; a first compound gear and a second compound gear; and a drive gear engaged with the first input gear on a first side of the drive gear, and engaged with an idle gear on a second side of the drive gear, opposite the first side of the drive gear. The first and second compound gears are configured for a simultaneous linear motion in one of two opposing directions.