Pulley and Rope

[minh714]

Hi! I try to design a pulley system use to lift a box weight 1/2 lbs off the ground 2 inches then lower it down. The box need to be really really stable, it can't move in any directions when being moved up and down. I have pulley, rope and a motor. What else do I need? Can someone tell me how to keep the box really stable? Thank you very much.

 

[Philrock]

Vertical guide rods.

Rod 1 has two linear bearings spaced vertically apart.

Rod 2 keeps the load from rotating about rod 1.