A simple seat mover. jrk 12v12 bord and "big motors"

Hello from cold Norway. I hope my spelling errors don’t upset you. But I have a hard time writing in English.

I have no experience with building things. I am an ordinary man with no experience in electronics and that sort of stuff. I have worked at an office and am not practical at all. So I may have some pretty stupid questions for you all.But i love racing. And have decided to challenge myself with building this seat mover. The stearing wheel and pedals will be at my desk. So its only the seat that will be moving.

A «noob» like me have problems with finding the right parts. So I will try to make links to all pieces I have to buy. So that other “noobs” can use my tread as a reference.

My plan is to build a simple seat mover. After reading this forum and watched YouTube videos I come across these to posts where I got my inspiration from.

http://www.xsimulator.net/community/threads/eao-robbies-static-sim-to-seat-mover-conversion.4650/
http://www.xsimulator.net/community/threads/diy-2dof-seat-mover-with-big-motors.4683/

Thanks to @eaorobbie and @bsft for your inspiration.

I must start with collecting bits and parts for the motor setup. Ordering thing abroad takes very long time to arrive to Norway. And we have a very eager custom service so parcels can be stuck there for a long long time.


Here is my part list that i have figured out myself.

Motors from ebay. 2x. http://www.ebay.com/itm/370915744975?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

2x Jrk borad from Pololu http://www.pololu.com/product/1393 Pololu
2x usb cable http://www.pololu.com/product/130


This seems ok??

And now the tricky part

After reading the forum posts. I understand that I need two pots. But here I got a dilemma. Rob uses single turns pots bolted directly to motor shaft, BSFT use 3 turns with gears on the motor shaft to turn the pot. I must admit that I have to Google pots to understand what pots are doing. So I have no idea of pro and con regarding single turn pots an 3 turns pots.

I hope that someone can help me with this dilemma. And give me an advice. And a link to a pot that I can use. If they have these pots at Pololu I would like to buy from them. So I can get all in one order.

I must cool down the jrk as well. But I have pc fans and some old cpu heat sinks. Can I use them for that purpose?

Do I need any other key parts regarding the motor setup?

Its beena long day
I use these gears http://www.jaycar.com.au/productView.asp?ID=YG2632 , large gear is bolted directly to the motor shaft and next size gear is glue to the pot shaft.
it gives me about 1.8 turns of a 3 turn pot. http://australia.rs-online.com/web/p/potentiometers/4601900/
Heres a video of gears on my big motors
1.8 turns is still plenty resolution out of a good quality pot.
With the JRKS, yes use a heatsink of whatever you can find, sit it on the big chip with some thermal grease and fan cool it.
Not much else in motor setup, a bracket with holes drilled in it will do for motor mount, a 3-4mm flat bar cut to size, no more than 50mm CTC. Rod ends of 10mm size PHS10.
Might have missed something.
Cheers, David.

Yes you can gear the pots but the lovely thing about the jrks is that you do not really need too.
To get up and running while searching for gear/pullys etc , it is quite simple to use a 12mm bolt of about 100mm long, on the head side mount the lever to connect the sim too, I actually weld the lever in place.
By locking a nut on the other side we have have lever installed, the hollow shaft of the motor has a 4mm hole through it too here I use a 3.2mm split pin as the drive locking pin so the bolt will always move with the motor shaft.
Now to connect a pot, I simply drill out the other end of the bolt with a 6.5mm drill bit, this allows for the shaft of the pot to fit snuggly into the centre of the bolt, then I drill a 3mm R clip through the end of the bolt and shaft to pin all that in place, and makes it all easy to service later on if changes are needed or something breaks.
I just make a simple triangle to mount the pot onto and is bolted back to the same motor bolts so if the motor comes alittle loss for all the wicked motion the pots centre doesn't change and I don't loss the feedback control on the motor.

Showing lever end with split pin in to lock the bolt to the motor shaft.

Showing how I mount the pot with the triangle, thread rod and a combination of nuts used to mount the motor and the pot to the motor mounts.

Another method that works too.

Now I use 65mm levers and 180 deg of throw is equal to 130mm of lineer movement at the chair, cool for flight games, but I mainly race so all I have to do is load a second firmware in the Jrk Utility which has my FeedBack(Pot) only using about 60 deg of the pot, the Jrk then takes the min and max reading that you have manually set and splits them into 4096 positions of possible movement, but because its only using 1/3 of the pot the change of positions can be a little fast and radical, this is what you want for racing indeed.

The beauty of this you can that we can have a couple of different settings in the JRK and if for some reason we decide we want less or more movement , we simply remap the max and min setting in the Jrk , and SimTools just carries on using it at the new range. This can be done in SimTools too by limiting the axis but I prefer to use 100% and let the Jrk do all the thinking, what its designed to do.
I have include my PDF plans of the basic construction to my seat mover, just in case.
(I must finish my other post, Sim is finished and done something like over 400 online races in it)

Wow. What a response. Thank you all. This must be the best community in the world. So much know how.

I can now order everything that I will need for my motors to function. I even got the plans for the seat mover.


I am very sure I will have plenty of questions when my parts arrive and I actually start building the rig.


Thank you all again.

Thought I might toss this in here too,
How to wire a Jrk for SimTools use.

How I wire a dc car battery, beware the rocker switches (red ones) have an internal led in them so the earth (gnd) connect is not needed if using ones that don't have a led in them.

That should just about get you rolling along.
Please feel free to copy anything and include it into your First post to create a build log.

Hi Magaplask.
How is your project progress?
I'm from Norway aswell, and just started on my 2DoF (probobly end up rebuilding it to 3DoF).
I've ordered 2 x JRK's and are planning on using wiper motors from a rear wiper taken from my drift car. (weight reduction in the rear ;-) )
Ive got Logitech G25 and a complete playseat, so I intend on just mounting my entire playseat to a frame and move entire frame (full frame instead of seatmover) but stationary screen anticipating the arrival of Oculos Rift.

I've bought my JRK's from England and with their awesome customer service, I end up paying 1500 kr for both. (my guess would be that you ended up paying at least twice that amound ordering from Pololu?)

My estimated budget for converting my exisiting "sim" to a 2DoF is 2000 kr. (300 dollar)

Always good to have another Buddy Local whom you can bounce idea's off and Share ideas. Keep up the hard work.