What cha think of this? Grapple..

mjncad · May 22, 2009

I've seen linear actuators in Surplus Center's catalogs. I think they would have plenty of uses; but a grapple is not one of them.

jinman · May 22, 2009

Electric actuators have come a long way. They are capable of huge loads, 16 tons is what I'm familiar with. These actuators are replacing hydraulic actuators for demanding tasks like the motion bases of full-motion flight simulators. In the attached PDF file link, you can see the side-by-side photos of an electric system beside a hydraulic system. The hydraulic system has huge electric motor driven hydraulic pumps (normally below ground level), plumbing, and large accumulators to provide instantaneous response. The electrical systems use 1/4 of the power and require little infrastructure. This allows for quick installation of the motion base and easy access for maintenance. It also ensures that there will not be the inevitable hydraulic fluid floods associated with a failure of a hydraulic line.

CAE Electric Motion System

Having said this, I think the environment for a grapple is much better suited to hydraulics. A hydraulic cylinder piped to the tractor's existing hydraulics would be much more reliable in my opinion. Mechanical gears and jackscrews of small electrical actuators are prone to problems. By comparison, the average hydraulic cylinder's operation is much simpler. It also does not have the ability to short out and cause electrical problems. I just don't think a tractor's electrical system is designed with these types of loads in mind; whereas, the hydraulic system certainly is.

woodlandfarms · May 27, 2009

We use these electric actuators in Theme park rides. Problem is the juice. You need lots of it. Response time is amazing and failure is reduced, especially important when it is about as many butts in the seats as you can get. They don't look delicate, but have not seen them in an industrial (dirty) application.