Never done it myself. And I am pretty sure that the add on systems are very expensive for the average joe.
I have to admit that I am in the same boat. Love to use the M816, but it is pain in the ass, as well as the joints, getting on/off the truck. Especially when you just need to move it 1/2 inch up/down/left/right.
I would think it wouldn't be too hard to rig something up. You could use some electric actuators that are bolted to the top of the control panel and have pins on the other end to lock onto the controls when you want to use it. Wire that up to a little wireless control panel and you are all set. Only big problem would be safety. If something goes wrong, you need a way to kill all power. But even that wouldn't be too hard to rig up.
It sounds like we're thinking on the same page. My mental picture has a bank of four actuators mounted on top of the panel over the valve body, with linkages going back to the vertical levers that actuate the poppet valves. I'd want to use some sort of actuators that move freely when unpowered. That would let me continue to use the manual controls without having to disconnect the linkages, and I could include one or more emergency stop buttons on the truck body that simply disconnect power to the remote control circuitry.
These are the characteristics that I think that the actuators need:
- Both push and pull with a travel of around three inches (just a guess; I haven't climbed up there to measure the valve lever displacement at the point where the linkages would most likely connect yet).
- For safety reasons, they should release the levers and move freely when unpowered. This rules out things like acme screw linear actuators.
- They need to be able to proportionally actuate the valves.
- Closed loop position control (like in an RC aircraft servo) is not necessary, since they're pushing against a spring and the operator naturally closes the control loop by feathering the control to get the desired reaction from the crane.
Off the shelf pneumatic rams would be ideal mechanically, but then I'd need to figure out how to apply air pressure that's proportional to the remote control displacement. The fail-safe part would be easy at least, because I could include solenoid valves which vent the air lines when unpowered.
An electrical actuator like a solenoid would be easy to control electronically by giving it a regulated current that's proportional to the remote control displacement (force is proportional to current in a solenoid), but the off-the-shelf solenoids I've found so far either push or pull (force is only applied in one direction), and they have short travel.
Aircraft R/C servos don't seem sturdy enough for this application to me.
I've seen one commercial system online that appears to actuate the equipment's hydraulic valves with its own small hydraulic rams, powered by its own little hydraulic pump. That seems over-complicated to me.
Ideally, I'd like to find something that acts like a pneumatic/hydraulic ram mechanically, but like a solenoid or motor electrically. I haven't found that yet, but I'm still looking.
Remote wireless controls are used everyday, it would require electromechanical valves wired to the multi Chanel receiver, very doable just only $$$$
I've seen it done two different ways:
- Hydraulic control valves are electrically actuated, and are then controlled at one or more locations by wired and/or radio controls.
- Hydraulic control valves are ordinary poppet valves with manual lever controls, and separate actuators push/pull on the levers for remote control. For example, on the Grove cranes that I've seen on some of the rear body units of PLS trucks, you can clearly see conventional lever-operated hydraulic valves with exposed linkages leading up to a separate bank of actuators.
I'd probably use the first approach if I was designing a new piece of equipment from scratch, since that turns the controls into electrical stuff as close to the hydraulics as possible, and then it's in territory where I'm comfortable.
I think the second approach makes more sense for this sort of retrofit, where I'd prefer to leave the original hydraulics untouched.
In either case, I think I can roll the electronic and/or radio portion myself for less than a ready made commercial system. I'm an electrical engineer in my day job, so that's the game that I know how to play. I haven't found the right actuators yet, though, and I have less experience in that area so far. So, I don't know off the top of my head what stuff is available off the shelf just yet.
If this brainstorming does end up with me adding remote control to my wrecker, maybe others will want to build the same thing? I think that the same hardware would probably work on at least three generations of 5-ton 6x6 wreckers.
