Low budget 2DOF Desk racer

I would say you to check if you have a "space" in your simtools parameters
but it doesn't work with serial monitor... so I cannot fancy what you have done, yet.

Please copy/paste the entire genuine code back into the arduino: you may have change something without notincing it!

I double checked everything - no space in SimTools parameters, and I uploaded the entire genuine code to Arduino. Same problem.

Any other genius ideas??

Sorry for the Woes Benj, But can you maybe see why some of us choose to use JRK's instead.

Yep, I can see that! The JRKs look great but not in my budget. I literally had the motors and Arduino and sabretooth laying about so that's my route

Still, I wouldn't call these woes just problems to solve and I like problem solving!!

I wondered if my battery wasn't up to driving 2 motors under load so fully charged it but still the same issues.

Now thinking my wiring my be wrong with the pots....the right motor does jitter and the left does not so maybe it's an earthing properly?

the jittering is not good...

Be methodical:
- swap right and left motors
- if you disconnect the left motor at motomonster? does the right one move?
...

Send pictures of your wiring

Thanks guys - your help is amazing, thanks so much.

I fixed the jittering by supplying the Arduino 5v from the Sabretooth. It's all nice now, but still have the problem. I've carefully rewired everything, tried swapping motors, potentiometers, tested voltage, it all seems good.

Is there anyway to make SimTools output the L then R commands as separate serial commands? Does the interface output field accept a newline or other character that might split the output?

Here is my wiring diagram, hopefully readable!

Fixed!!!

Turns out it was the serial port settings. I finally got the code to echo back the serial commands, and noticed it was dropping characters!

When I sent L12, that was fine. Went I sent L12R34, it echoed back L14....

Turns out my hardware can't handle the 115200 baudrate. I've had to set everything to 9600, and now echo's are correct...and my sim works

edit: I run a Macbook Pro using Bootcamp, Windows 7 64-bit. I bet it's the dodgy Apple drivers for the com port

Couldn't of done it without this forum and the guys who have chipped in their help, so thanks again folks



Those wheelchair motors really pack a punch, I reckon this is going to be a lot of fun once everything is dialled in!

Time for a video. As usual with my work - please excuse the lo-fi nature, portrait video and general 'quick and dirty' As you can see, the chair has got some really great movement Yes - I have sat in it with these settings - it was quite an experience!! Lots of profile tweaking needed.

Just one issue to solve, if you skip to 2:55 in the video, you can see the chair goes a bit mad. The pitch seems to go crazy, rocking back and forth. This happens about half way round a track on Dirt 3, and it carries on doing it until you quit the game, at which point the chair smoothly moves back to it's center position. I've not had time to debug this yet, but pretty sure that shouldn't happen!

Great job, nice shaker!
What's the height of the seat?

The seat base is about 275mm from the floor, that includes the bottom wood, UJ on a mounting plate and the top wood. The seat is on runners so it's a bit higher than that, but I am fairly tall at 6ft 2in and it seems quite comfortable for me.

motion looks good, well done. I think with Dirt3 the seat does that, it keeps wobbling till it goes back to menu. I will re-install dirt3 soon and check

Yes, I've noticed that and wanted to comment about it. Something seems wrong - if you look at the chair position at beginning of the video when motion starts and then jump back to the end of video where the motion is about the end (before pause menu rattling) - the chair is ended up being tilted backwards much.

Have you tried without pitch to see if that's the only problem? Try just Surge and Sway effects and see what will happen with positions after the race..

I've not tried without pitch yet - that's a great idea. I will try and play around with it tonight.

work with each force one at a time, get the direction of it moving right, work with tuning centre numbers, then go to next force. Rinse repeat

Thanks @bsft, I will certainly do that. I tried it without pitch as @prodigy suggested and still had the same problems.

It also happens in Live For Speed. Not quite sure what's triggering it, I think if you drive carefully and smoothly, it stays OK, but if you crash or hit it hard, the motion never recovers quite right.
Anyhow, I will take it 1 step at a time. I don't get much time to play around as there is a newborn in my house so it makes finding time a bit tricker

I used to play Dirt3 without this problem... Hope you found what happens to your rig!

OK, this narrows the possible problems. If it happens in other games too, it's not game related, possibly Simtools profile or ARD code maybe. I'm not too familiar with arduino so we can check the Simtools profile first

Have you used Tuning Center to capture and save min/max values for a game? Driving some clean laps (without crashing) while capturing those settings and then saving them?

You want me to drive without crashing!!?

I gave it a go but same results. I think I might've found the problem .... My battery.

I am using an old car 12v battery. It was struggling to start a car so I've been charging it up and thought it was ok - however I just tried another car battery and the whole rig is now much snappier and happier!

Completed 3 Dirt races and several No Limits tracks with no problems so far

I wonder what happens in the PID process if the motor can't reach its position?

Looks like I will be saving up for a server PSU next!

You don't have to save that much, the DPS 600PB (12V 47A - 575W) on the bay can be found for real cheap