Double wiper motors per axis?

It probably has been tried before?

With a little thought using a couple of extra pulleys, it is possible to use 2 motors to drive 1 axis.
This would nearly double the touque available - so maybe increase the size of the drive pulleys which would increase
the speed / acceleration of the system.

Also as a refinement of this idea, is it possible to drive the 2 motors from separate channels of the DIY controller in a master slave arrangement? This could enable feedback correction for variations between the performance of the 2 matched motors.

Bruce

You should be able to use two motors per axis, as long as the speed of each motor is the same. If one motor is slightly faster than the other , it would obviously cause and issue. Do some tests to see how you can find a suitable way of setting it up.

Thanks for the reply bsft,

I have sussed a way of using a pulley that automatically compensates for the different motor speed. It converts the speed difference into a rotation but still allows the 2 motors to pull in a linear fashion.
I will try to do a drawing soon to share my idea. It seems that the only critisism of the the wiper systems (single motor) is their inability to accelerate at a fast rate. Maybe this might be a possible improvement?

Bruce

Done a quick sketch of what I was talking about. The centre pulley is attached to the frame to be moved.
You can see that if one motor is slightly faster, the centre pulley rotates but is still displaced by the linear motion of the 2 motor belts. If the speed of the motors are the same, the pulley will not rotate and you will get maximum speed of linear motion.
I think this will work???

Bruce

Wiper motors move about 80mm per second, within reason, if you increase voltage from 12 to 14 volts or a bit higher they may move a bit faster.
Mine seem to go ok on 12v http://www.youtube.com/watch?v=sgO5osurtm8
Otherwise SCN5 actuators are the next option but not cheap. However they do move a lot quicker.

This should work, build a test model and throw some weight at it. Motors will move better if you get your weight balance on the sim right, depending on what style you build.
Have a you a sim type in mind?
Cheers, Dave.

Hi Dave,
Thanks for your interest. Yes I am going to build a joy rider derivative. I will use thin walled RHS with 6mm steel rod bracing structure. Should be strong and relatively light. I will also make the frame pivots adjustable to get the balance right. I should have about 400mm of adjustment!
One question, Is a car bucket seat OK? (weightwise) or should I go with a comercial plastic racing seat?

I will repost this on a more applicable forum - DIY Motion simulator projects

Thanks,

Bruce

heaviest of bucket seats is still very light for what they between 3-8kg

Gday mate, built a simular unit on the acesim spec but used 25SHS 1.6 for inner gimble then used 35SHS 2.0 for the outer and the same with the base frame plus 65RHS35 for the uprights. Attached box section to carsters to make then slide up and down the two gibles and tec into place once the right balance position is found for different pilots. Resulting in a light frame with very little flex plus a couple of tec screws and the balance is easly change. But havent motorised the unit only set it up like the real joyrider, its and oversize joystick you sit in.
There was another way i was looking at setting up dual wipers, 3 bike rear sprockets joined by chain (cheap) two attached to the motors and the middle one to a pully or even a car steering box or rack, just another idea to think about mate. I was going to connect to to a sabertooth 50amp motor controller then back to a arduino microcontroller since the bug with the k8055 makes it unreliable. And use tronics single wire pully setup.
And yes time to start a pre build post.
Welcome to X - Sim.

P.S So where are ya, im in the west.

heres my old joyrider frame. I built it from guesswork more than anything. http://www.youtube.com/watch?v=fKAcXtnxHXU . It has since been dismantled as I plan to build another, but a bit longer. This one was a bit short for my height.

I'm in Tas.
As far as the weight of seats is concerned, how important is it to keep the weight to a minimum if I am going to use wipers? (for a racing sim)

A few people including myself have made our own seats from plywood, which can be light. Look up a DERIY post for seat design. Also with the joyrider, good weight balance is the key as well. Do some research into other peoples posts and as for help. You will find we are a helpful bunch, but do some scrounging as well.
Thanks, David.
Heres a few photos of what I did,



Hope it helps.

Thanks, The ply seat looks fine. Although for about 150 bucks you can get a light racing seat. I supose you have to consider the cost of ply, foam, covering etc. You could save a bit.
Thanks for the photos I can get some ideas I can use.

Yes, I know, I can get a good racing seat for about $180 here, although I had the plywood, foam, and fabric already from ages ago, so despite the time spent, no cost. I may put ina decent seat sometime, but as I do not get to play on it much, I cannot justify the cost.