Showroom 12v Winch Motor Driving Simpit

Thanks Dave! That took care of it. One odd thing though (ok, more than one, lol); when I adjust surge, roll, pitch etc in the axis assignments and save it the next time I run the sim they are backward or ignoring any changes. It seems random, I can start and stop the sim (Dirt 3 and Grid 2) make changes, restart and changes are ignored, or oddly...sometimes implemented on one dof but not the other (even though I had made changes to both).

The other odd thing:

My left motor is creeping up. About half way through my first run, no matter the sim, the left motor starts to get higher and higher. By the time I am finished it is 15-30 degrees higher than when it started. The right motor is still in its proper place. I checked to see if it was the clutch but there was no slippage there, surge and pitch did not seem to affect it but when I also tested (in simtools test) roll it would creep up within four or five rolls.

I would have assumed that because of my weight and the weight of the sled that it would have slipped down not up.

Could the pot be causing this? Why always up not down?

Are you using the ard still? If so I cannot help.

Yes, still using the Ardiuno. I sent back the JRK 12v3's and am waiting on the correct shipment.

This creeping is weird !

As I know that you have checked for pot slippage and that it is securely fastened, so it's probably not this cause ... but please send more pics about this pot mounting !

and try with Jrk's to see if it's the same ! until then, poor arduino is accused...

I would lean toward a pot issue myself. I doubt the Arduino is to cause.

I have an idea that I will try later today when I get a chance, the pot might have too much sideways force and that might be causing some internal issues with it.

[strike]Creeping is due to the motor not receiving enough duty cycle, IE Amps, then will draw over 30amps in stall, recorded up to 38amps of a change of direction before on the old girl, hence I was using the Jrks that will peak at 30amps odd without an issue.
Basically the lack of amps coming from the driver is not enough for the stall current the motor can draw, plus your sim is out of balance , one sides heavier than the other, another thing that helps is the dia of the wire going to the motor to driver , for amp draw 3-4mm recommended and short as possible too helps.[/strike]
Normally rolls down if not enough amps but if sim is front heavy then the above is correct.


Ah your issue thou might be internal wind up of the values or non linear pot usage or yes undue stress on shaft , on cheap pots I haven't had an issue with, my centres are not perfect.

Can a lcd be hooked on to see if pot values are changing and its not the driver. ?
And did this do this on the 24v motors. ?
Sorry a mess of idea's. One will be right, not being able to see what the driver and ard is doing makes it hard.

Hi Rob, thanks for responding.

I readjusted my CG when I added the monitor to the sled, and then moved it again toward the back another inch just in case. That was a couple of days ago and I am still having those issues.

I thought too that I might be out of balance toward the right (my shifter assembly, etc) so (and yes I looked awfully funny) I held my left leg out at an angle to counter balance. Believe me; my left leg is far heavier than the shifter, lol. It still has the same issue.

I need to mount my amp gauge somewhere so I can see it while driving, right now it is mounted behind the seat. Kind of defeats the purpose I know

The pots are not cheap, they are Bourn units about 35.00 each (yes, I know there are much more expensive units out there, haha). But that does not mean that they are fault free. Even expensive items can be lemons. I am going to swap that pot out with one of the others that I have. I think you might have hit it on the head if I am not right about the side force. Although both pots are Bourn 10 turn they are slightly different model numbers. As far as I can see from the spec sheets they are different in their housing only, one was made for a specific mounting scheme but perhaps they are also different internally.

No idea how to mount an LCD on the Arduino to view values but that sounds like a great idea.

I never had the system operating sufficiently to actually ride on it with the 24v motors. The winch motors arrived the day I had it all figured out and I jumped into using those instead.

I wonder if there is a logging function to show what the Arduino is doing while in action? Something saved as a text file perhaps?

Thanks again for the suggestions.

Another one that may cause it to wind up like it is can be a bad pid setting, normally too much D in the PID, or not enough P , becomes a balancing act. So it doesn't overshoot or undershoot, another biggy we had with the ard is the port speed, with my pc anything above 9600 cause communication errors special if my pid period is too low, don't know exactly how matt as implemented pid in his code.
Sounding a little better though.

Success!!!

The problem was indeed the side force on the pot, no idea why but now it is all cleared up. I turned the force up to 100% and the axis travel on all DoFs up to 100% and took it off road! (Dirt3). Several runs and the axis both return to center.

Holy crud they gears are loud though. Any thought to my ideas of making covers for them?

Success!!! Did I mention that?!!

My 2DoF motion rig is now fully functional.

Thank you to everyone who lent a hand in this build, without which I would not have been able to do more than weld a frame!

Thanks also to SimTools for providing such an easy to use software interface.

Hmm....only bad thing is....what do I do with the two JrKs that are now not needed? I know!!! I will start a 3DoF flight platform and use the Arduino for that and the JrKs for the DoF rig!!!!

Can you tell that I am a bit happy?!

Groovy, Its moving, well done!
Noisy motors? Turn the game volume up. They are a winch, expect them to be noisy.
2 spare JRKS, pack them up, I am sure there will be another build in no time......mmmm.....2 more winches and jrks, turn the mech pit into a 2 DOF.

lol, no...I am going to go with the 3DoF flight sim pit. I bet the winch motors would heave the Mechpit though

I have to thank you Dave, you talked me into this in the first place and you were 100% correct. I could do it (with lots of help) and I do enjoy it.

Hey, no worries, just here to help like other on this forum.

Well done, mission successful.
Yep turn the sound up, did warn ya they are noisy but bloody strong.

The code is shortest as possible and deals only with Proportionnal for PID control.
I like the Kiss approach of pid: Keep It Simple and Stupid :rofl:

It feels good but I think i'll end one day by trying jrk's on my hardware in order to compare !

yours,
Mat

Yes agree mate KISS is my method too mate, specially when some user need to translate it to read it too.

Sorry I haven't had the time to actually step through you code, new job kept me busy.

Jrks are a simple approach of getting a newbie going and they seem to learn a lot and most progress onto a DiY approach next, I personally know the frustrations that one goes through in trying to build something that hasn't been repeated successfully much(AMC early model). But with a backer like yourself , yours has proven to be a good one. I've personally helped over a 30 users in the past 2 years complete Jrk builds most drop in ,get the info, setup and almost never hear from them, until running into them on an online race, to find out its still running as built or been a little issue and they have been able to source the issue and fix on their own. Early days mate.

Don't stop developing the Arduino Mat!!! NOOOO!!!

I am very much glad that you were around to help with this, now that I have it up and running I believe that it is as good as the JRKs and much cheaper. Yes a higher learning curve but with you, Aaron and Rob as a resource it is well worth it.

I have to be honest, I am replacing my Ard/755 combo with the JRKs but that is only because I already ordered the JRKs and I want to re-purpose my Arduino setup for my 3DoF flight sim rig. Your Arduino sketch allows me to have all three axis on one micro controller, and huge benifit in my opinion. As well as the ability to add either more axis to the same controller or add more controllers (thanks to Simtools) to one rig. I see the Ardiuno as the perfect mate to motion platform building in both cost and ease of access.

On a side note to the Ardiuno sketch, have you ever looked at the Teensy micro controller? It is Arduino compatible but has a greater range of inputs and outputs as well as being faster. I wanted to try to program one of mine (I have a dozen for various joystick controllers) but there are slight differences between coding for teensy and coding for arduino that I do not know.

http://www.pjrc.com/teensy/index.html

Hey Dave, can you share with me how you connected your power supply unit along side the battery?

Are both connected to a buss and then connected to the JRKs?

Or do you connect the PSU directly to the battery and then connect the battery to the JRKs?

What is safer?

http://img214.imagevenue.com/img.php?im ... _653lo.JPG
This is the pic, mind you, I since advanced a bit then, plug in between psu and battery, plug in between battery and cable to jrks. I have to unplug and re-plug in, I could put in switches but am lazy.
Plug to disconnect psu to battery important and volatge feedback when power is off. Doesn't damage psu, but a safety feature. Same with plug from battery to jrks, disconnect after use.

Nooo, you're pushing me into temptation ! :happy:

I'll have a look !
but I need first to find a way to measure speed of arduino's program loop vs serial reading.

I'm currently on the verge to fall into this brushless wheel's temptation ...
http://www.racingfr.com/forum/index.php?showtopic=45950 :clap:

Hmmm....AC brushless servo motors. I had thought about them but the cost was just too great. When I built my CNC router table I used 382oz-in ( 2.7N-m) stepper motors. I had wondered if anyone had used CNC purposed servo motors for motion platforms.

The price, with driver and encoder with 2559 oz-in (18 N-m) here is 1019.00 USD. I can get 200W sets for 600.00. If I could afford it I would certainly grab a set to play with. But that opens a whole nother can of worms, namely my divorce