For superior trolley performance utilize a SATURN Hoist & Tractor Combination.

The consistently POSITIVE action of a drive tractor will generally out-perform a standard motorized trolley in many monorail applications.

By combining a drive tractor with your hoist, you will better negotiate curves, ride up inclines and will eliminate nuisance slipping in many severe working environments.
 
Furthermore, the inherent beam tension of a drive tractor can also serve to RESIST motion in certain applications particularly when load swing or side-pull present motion issues.

Please see our photos below for some examples.

Rope Guide Hoist with Tractor Drive

Semi-Low headroom Hoist with Tractor Drive

Twin Hook Hoist with Tractor Drive for Outdoor Use on Curved Monorail