A ball lift assembly includes: a housing having an entrance and an exit; a motor which drives a ball lift system; an electronic control unit (ECU); and a plurality of sensors providing signals to the electronic control unit, including: a first sensor which detects a ball entering the lift system through the entrance; and a second sensor which detects the ball exiting the lift system through the exit. The first sensor provides a first signal to the ECU when the first sensor detects the ball entering the lift system through the entrance. The second sensor provides a second signal to the ECU when the second sensor detects the ball exiting the lift system through the exit. The ECU will turn on the motor to drive the ball lift system upon receiving the first signal, and turn off the motor of the ball lift system soon after receiving the second signal, while making sure the ball actually exits the unit.

A box-shaped protective cover that covers an upper structural portion of a body of a vibrating compactor is manufactured by executing a cutting process for fashioning a single metal plate into a shape including a first planar portion, a second planar portion, an intermediate portion, and a plurality of side flaps, a bending process for bending or curving the side flaps and the intermediate portion, and a welding process for welding a side flap of the first planar portion to a side flap of the second planar portion.