2Dof + Traction Loss JRK/Worm Motors Sim

Hi Everyone!

So i've been a bit slack and should have put this up a while ago but hey, better late than never right?

Inspired by so many amazing people on this forum i decided to start my own motion simulator build about 6 months ago, though i'd been looking into it for about a year before that.
I decided on a JRK and worm Gear motor setup as it seems to have a good cost/performance balance.

When designing my sim i wanted it to be as adjustable as possible as well as being able to accommodate both a racing bucket seat and a fiberglass go kart seat (as i race karts) with the typical seating position for the different styles as close as i can get it.

So as of last night i finally got it to the stage where i can sit in it and move it around, however it is still very much a work in progress with plenty of bugs as you can see from the photos.

I'm very excited to finally be sharing this with you and am very keen to see what people think.

Im hoping to put up some images/files from solidworks that ive been updating along the way for people to look at to get a better idea of how ive put it together,cause i know my cameras a bit woeful...

This is the stage thats it currently at.
The PC is designed to sit on that shelf you can see below the monitor but im currently waiting on ebay to deliver me my longer usb leads... Also that monitor frame is completely separate and independently movable to the sim frame.

Ill try and add more photos because it didnt let me post this when i had a few more in the first time...

Thanks, i actually just tried it with the kart seat in it for the first time with race07.
i expected it to be much more violent than the bucket seat but was pleasantly surprised!

About to look at retuning my PID settings ow thought as i sometimes get motors cutting out randomly.. or the blinking green light of doom making me disconnect and reconnect the usb...

@Shadow041 , nice sims there, and good to see JRKS back on the scene.
As for issues, p[lease post all screen shots of JRK utility program and we can advise.
Cheers, David.

Hokai, so i just properly tuned my PID settings and the sim feels much better however i am getting more motor drop outs and 0x0800 serial protocol errors...

here are my settings;

now ive currently got the basic 25:1 worm motors from motion dynamics and have tried to set my balance point according to tutorials that i found here.

however i find that when i sit in the sim with my feet on the pedals the seat wants to drop back and rest on the motor arms... i'm wondering if i need to move my balance point back further to help this issue as im wondering in this is putting more stress on the motors, hence causing some of the drop out issues..

love to hear what you guys think!

mmm....PID looks ok, maybe drop max duty and max accell to 500 for both. Try dropping current calibration down to 120.
What pots are you using?
What length levers you got?
maybe the percentages and tuning centre numbers need to be looked at next
Also please take a shot of interface settings in game engine and also just a shot of a game and percentages used.
As for motors dropping, is that under power or without power?
If the motors are trying to bring themselves back up, thats overshoot, but it doesnt usually cause drop outs.

EDIT, what power supplies you using?

ok ill update those values and give it a shot, however i did notice that when i run the sim some cars, the stiffer high performance kind ie: F3000 or Radicals, seem to result in more serial protocol error drop outs than when i run say a bmw 320.

here is a screen shot of the error tab i get:


The pots im running are single turn hall sensors from digi-key #6127V1A180L.5FS
lever length CTC is 65mm
The motors dropping back when i get into it or at rest is only when they are off. when they're powered up they'll hold the position.

here are the interface settings:

the only changes on interface 2 is that its on ComPort 5 and it is labeled <Axis 2> instead of <Axis 1>

As for axis assignment and tuning center:



as it seems was recommended those tuning center values were set by capturing while driving around the track, not hitting anything or going offroad, in the bmw 320 i should add...
The percentages were set one by one to feel.

Ok your total percentages are WELL over the total 100 recommended like you have 220 %. So whats happening is that Simtools is throwing too much information at the controller causing them to crash.
You need to start again do one force at a time, set it at 20% and work with tuning centre numbers till it feels right, The move onto the next, rinse repeat. By doing individual forces, you have a better chance of keeping them towards 20% each mark.
Now dont panic if you cannot keep the total at 100% I cannot, most of mine are near 110-120%, BUT its better than 220 % , Also drop main level in game manager to 99-98. That will take a bit out of them.
And yes the motors will sag with no power in them. If you want them to hold with no power, use 50:1 or 60:1 boxes.

The sum of your axis is 220%. You should stay at 100% max, otherwise there wouldn't be any room for further movements once you reach the maximum

Also just as an update, ive since installed the traction loss module, fitted the lower floor for the controllers and hardware to sit on, installed speakers and sub and finished the computer and monitor stand! here are two shots of it as it currently stands. ill try and get some better shots next time i have it out to work on.


also on a funny side note. i currently have the kart seat in it to test, i'd been putting it off as i thought it was going to be very violent and possible leave brusies! Haha! But have been very pleasantly surprised! it is actually less violent than the bucket seat yet provides more sensory feedback and feels more realistic! Who'd have thought!

Oops we replayed at once. You can't say it's an helpful community

Ok so does that mean i need to drop those percentage values so they'll total 100% then adjust the values in tuning center to acommodate for the motion ill lose?

haha certainly not! You guys are most helpful!!

So could that be the reason im getting the protocol errors? im trying to send too many packets of data to the controller than it can interpret? beacuse im over by like 120%!

Mine is about 120% too because, for example, in plain tracks, pitch is - almost - not used and its % wouldn't be used too; this way I use all of the range

yes, start with each force individually at 20%, so say start with surge, set at 20%, fiddle with tuning centre numbers till it feels ok, then drop that percentage to 0%, then go to sway, set at 20%, fiddle with tuning centre numbers, once that feels ok, drop it to 0%, then work on the next lot like that, individually. Once you have a decent feeling for all forces individually, mix them all up, set all at 20% and go test, raise or lower each force % a bit if need be.