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Thanks for all the brake info guys.
I had a chance to play around tonight working on a throttle for the car.
I had the control stick off the forklift I took apart in my driveway in January.
The control stick is attached to a big aluminum box and has a button on the side (horn?) and a toggle switch on top, which I think was for extending the forks.
Opening the box, I could see there was a double-cam on the stick, 4 micro-switches, and a potentiometer.
Setting my Ohm meter on the wires from the potentiometer, it pretty much read all or nothing. When I turned up the setting on the meter, I could see it was actually a 1 mega-ohm potentiometer, I just couldn't see it on the setting I was using.
The whole assembly is designed so that when you turn the stick, the first micro-switch turns on, then the potentiometer starts reading, going up to maximum, then the second microswitch activates.
The other thing that is kinda neat is that the potentiometer turns the same way whether you push or pull the stick - it goes both directions.
I was able to pull out a TEENY TINY set screw and slide the potentiometer out. I then replaced it with a 0-10k ohm potentiometer from Radio Shack
I screwed down the entire pot box assembly to a piece of wood where I also attached the cable end of the throttle cable. I put two screws into the plastic handle of the forklift stick control so that pressing on the gas pedal pulls the stick. I also added an additional spring to help with the additional weight of the stick.
I connected my ohm meter to see that I would normally have 0 ohms, and should have up to 5K ohms when the pedal is pushed.
Sure enough, it measured up on my meter.
Did a test run. The "go pedal" is a little stiff to push. Also, it's a bit touchy, sort of hard to do a real smooth acceleration. The actual mechanical connections will need to be improved for the final version.
Again, I am simply experimenting, using what I have to figure out how all this works, without spending a fortune.
This all makes a lot more sense with some photos. I will take some tomorrow for ya.
-Ben
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