Articulated arm vs Forklift style arm

[Chris is me]

Originally Posted by sircedric4

For those with electrical arm and elevator experience, how do you keep your arm or forklift in the position you want it without power. How do you make the up and down appear so easy and controlled?

Our students built a four-link arm in the off-season for a game they made up. (We simulated a build season with them to get them ready for this season) They used one of the locking Dewalt transmissions and a CIM to drive the arm and while going up was good, controlling the down was difficult. We did try to do some balancing, but overall, once the brakes released on the Dewalt, the arm was too quick going down to control nicely.

My question to the veterans with really successful mechanisms, is how do they control their arms and forklifts so nicely? Do you build custom worm gear drive trains, or use really inefficient gearboxes to establish the same level of control going up and down? For balancers do you use torsion springs or gas shocks?

In a nutshell: Balancing. Make sure your arm is counterbalanced either through stored energy or weight and it will be a lot easier to hold up.

I've heard some people say they use a PID loop for this purpose and some people say not to, depends on who you ask...