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2DOF to 3Dof Seat Mover Moxley's Way

This is what I started with and decided to add motion with the help of a Few Key member’s of xsimulator.net/community/

47A 575w Server Power supplies from Ebay for a whopping 12.50$ Along with a pair of Pololu JRK 12v12’s

10mm Rod ends again from Ebay for 11$ free shipping with Lever’s and Holes drilled for direct mount 360deg hall effect pots.

Motor’s are 12/24V 200w, 20-30Nm

And Finally the Joint and the seat. CV has been angle mounted to match the 10 deg angle of the stock seating position.

Currently as of today I’m in the middle of rebuilding the Base to ensure it’s as sturdy and solid as possible, Gluing and Screwing everything. Paint job is 1/2 done on the base and all the little bits and parts are being painted as well, Tomorrow I might just have the Seat Mounted on the frame and then on the base. Very excited to say the least.

Paint in Progress

Seat Mounted and final measuring for rear arms.

Rear Arms Welded/polished up

Motor mount Angle L wasn’t up to snuff, So they got upgraded

Next up was the shifter mount, I couldn’t stand having my CSS sitting there staring me in the face not being used, So i went to work using the old motor mount angle iron. Here’s what i came up with. Drilled and tapped the Seat riser using 4mm cap heads from my RC stuff and managed to get it Exactly where i had it before. Its also Uber sturdy like it was before.

And Finished Project

Hello, Nick.

That is a great simulator! Also, nice job documenting it. We are planning on making a community project blog post about it.

Keep up the good work!


Awesome, This was a shortened down version of just the motion Setup. Got a whole build thread at the link i sent ya,

In case someone else wants to see the progression of the Rig.
insidesimracing.tv/forums/topic/ … xleys-way/

So On Saturday i had my first official test session with 2 “lfe’s” on the seat bolts and my Gamer 2 on the seat frame. HOLY CRACKERS!!! Thats what i was looking for/expecting from the LFE’s. Vibration’s that will make your eye balls shake to the point of not being able to read text. One thing i noticed was the LFE’s on the seat bolt are in a completely different Fq range than the Gamer 2 on the Seat frame. Kinda cool to be able to cover a larger spectrum of the Low end Stuff.

I also re did my motor locks, the Bent flat bar i had before would prevent the arms from Dropping down, but wouldn’t prevent the arms from Going UP when i sat forward in the chair to reach something. SO i came up with these.



Beawdy Job there buddy! I look forward to racing against you online with my ride.

Yes, nice job man!

Thanks Dave, Without your and Rob this most likely would have never came to be. Special thanks as you already know. :smiley:

Couple new mods to the rig,

Seat belts all sorted out with some spring tension. Im rather happy with it so far.

Thought i was going to go this route with the funnel’s but decided differently

Ice Cream pail is where its at, lol

1 1/2" drain pipe

2 main Runs come up the side and feed 2 vents which cover my chest, One run on the floor of the pedal box which will cover my legs.

the 4th line goes right to the back side of the pedals to keep my Feet cool,

and here’s the Bucket air box in its glory. I wanted to tuck it Under the pedal plate but the “suction” from the fan rendered the “leg” vent moot, Just sucked back all the air it was trying to blow.

Hey Guys, Im sure you would appreciate a Video of your boards in action, Well here it is.

Thank you for posting the video. It is great to see systems like yours in action, and it looks like a lot of fun!


You ROCK derrill, Thanks for the Stickers, I look forward to getting them. Ill be sure to post some updated shots of the other rigs im building when I can. :slight_smile:

you have done well man, its a great job

You as well Dave with all your builds over the years. :slight_smile:

Hey hey Guys, so Slight problem. left side seat motor decided to take a hike last night and cease to function.

Correct me if Im thinking right here, If i put my Volt meter on the Motor leads and ask the motor to move, I should see the Voltage change from + to - when asking the motor to move correct ? Also the + on my power side is now somehow joined to the - on the motor side after testing with a multi meter. All the LED’s appear to be working as normal when plugging in, but the motor just wont budge, Im experienced in the Utility so know full well how to control the motor and make adjustments…Nothing i did seemed to work or bring the motor to life.

The only real change is that Simtools v2 (program that talks to game and to JRK) is now using a more solid connection type to the JRK itself…im struggling to think of the name for it, but regardless there are Many MANY other guys using these exact controller’s with the Exact same motor’s with no problems.

Wiring hasn’t changed in a long time, so Overall im confused as to why it quit.

here is how they are wired…my Power cables from PSU to JRK are less than 3’ long, same with the JRK to motor wires.

I will say that when the motor was hooked up with power on and trying to get thing’s to work, the motor did feel somewhat notchy around the center when manually moving the lever up and down, When i un powered everything and removed the faulty JRK the motor went back to smooth again, so Not sure how that relates…but its what i felt when i was testing…im assuming as the + and - were joined that was part of the weird feeling on the motor.


Your wiring diagram looks correct. It is not clear to me what you are describing when you talk about measuring the motor output pins. Could you try measuring each motor output pin individually with respect to ground (e.g. with the positive probe of your multimeter on the motor output pin and the negative probe on the ground pin)?

From what you mentioned, it sounds like Simtools might have changed the communication in some way (maybe adding the CRC error detection or changing the baud rate). If this kind of change was made, you might need to adjust the settings on your jrk accordingly. Is the jrk throwing any error codes when you try to run it?

By the way, when longer wires are required for a project, we typically recommend putting the motor driver as close as possible to the power supply and having the longer length of wire between the driver and motor.


Hey Brandon, Got a Extension i can call you at ? would make it much easier to explain what ive tested and what i haven’t tested.

You could call our general support number and mention that you are talking with me on the forum, but I will ask you the same questions as I did in my previous post, and we generally find it is easier to troubleshoot over the forum (or email) since it is much more convenient to share pictures, links, and settings files. The forum also leaves a record of the troubleshooting and makes it easier for us to keep straight all of the details of your system and testing, which could be helpful to others with similar issues as well.


I measured to 2 the Motor out pins when everything was still hooked up, So Telling the Motor to move in both directions using the slider bar which i have used 100’s of times before, This proved to give no motion what so ever and No error codes also No change in + and - Voltage fluctuation. …I checked my left motor and got Fluctuation in the motor out pins, so that right there told me something was up with the JRK itself.

I then dismounted it and took it to the bench where i happen to have a buddy’s JRK handy, I started checking continuity on a few thing’s and found out that when i probe the + on the Power Supply IN, and the Negative(B) on the motor output i get a signal, When checking Buddy’s JRK i found this not to be the case, Further cementing the fact this is solely the JRK and nothing to do with my Currently working setup (swapped JRK for a spare)

So what else is there to test aside from sending it to you to check with far more knowledge and experience.


If the jrk is being detected by the Jrk Configuration Utility and responds to changes without any errors, but cannot move the motor, it sounds like the driver IC might be damaged. Just to double check, if you move the slider in the Jrk Configuration Utility, you can see the plot of the duty cycle changing, but no voltage change can be measured on either of the A or B motor output pins; is this correct? Can you post some close-up pictures of both sides of your jrk controller so we can see if there are any visible signs of damage?

If you would like to do a little bit of troubleshooting, we might be able to determine what caused it to fail. What was the controller doing when it failed? Did anything in your setup or settings change between when it was working and when it stopped? How long was it running before it failed?