Showroom DIY 3 DOF inspired by DOF Reality H3 model.

The rig I wanted to build was meant to be relatively small to replace my old racing rig. The design that best met these criteria was a rig similar to the DOF Reality Model H3, and I based my project on that concept.

The entire construction took place in the workshop where I work every day. The work was done after hours, usually about 2 hours per day.

I intended to build my rig as cost-effectively as possible, so I used old metal profile structures that I found at a scrapyard. I purchased used motors from a Permobil wheelchair, labeled CIM CM808-077A and B. Additionally, I acquired 3 potentiometers, 6 motor drivers IBT-2, and an Arduino Uno R3 clone, and that's how I started. Meanwhile, I bought a used gaming chair, an electrical box, 3 pcs 24V 400W power supplies, potentiometer connectors, and spray paint. The packages arrived during the construction of the rig.

Week 1:

On the first day, using the Dof Reality H3 assembly instructions manual, I designed the main support frame. The next day, the frame was ready.




Next, I made the second movable frame, for which I needed skateboard wheels and a roller bearing to connect both frames.

Week 2:

The next step was to build the side frames on which the structure holding the chair is to be mounted.




On the side frames, there was supposed to be a support with a U-joint, and the chair frame and pedals were to be attached to it.




to be continued...

Week 3:

The next task was cutting the plate for the pedal set and fix the frame.




Then, I added sliders under the seat for position adjustment, next I wanted to paint the frames I built at the beginning.




Finally, it was time to install the electric motors. Two mounts were included with the purchased electric motors, so I had to made the third one only. And I had to create link arms for the motors that would drive the seat movement.



In the meantime, I welded nut brackets for the rig's adjustable feet.


As the previous U-joint support seemed too high, I decided to make a new, lower one.



Next, I had to fabricate a frame to support the steering wheel base plate.




Then, I temporarily mounted the seat and adjusted the distances to the pedals and steering wheel.



Another metal plate will be installed under the steering wheel. And needed to make the third plate suport to preventing the steering wheel and base shaking.


Afterward, I decided to create shelves for HOTAS controllers for flight simulation.


All elements were then prepared for painting. After some consideration, I decided also to change the frame for the pedals set and also paint this frame.


The next step was to mount the potentiometers for the electric motor axes.


And wiring for the potentiometers and electric motors.



Finally, it was time to install ball joint linkages and assemble all the painted components.



Week 4:

The following day, I started building the power supply box with all the electronic controls for the motors.


The first motor tests in the SMC3 program were successful.

The next day involved transporting the rig to its intended location for use. There, it underwent initial assembly and the first tests in the game Live for Speed.



The following day involved disassembling the old rig and transferring components such as the steering wheel and accessories like the bass shaker to the new rig.


And so, after about four weeks, it stands ready for use, bringing joy to its owner.

And the most important information I left for the end.
The main inspiration for creating this rig were the videos by Dave from the channel https://www.youtube.com/@DMAX_DIY.

@Halloween2go Dave, I would like to sincerely thank you for the inspiration and wish you continued success, many followers, and immense joy from using your constructions. Great job! Thank You!

Good tidy job on all the fabrication!

I am really impressed by your build, so compact and tidy. Would love to get my hands on the drawings for this if possible. Cheers!

hello! a very cool project! tell me, did you connect 2 BTS per motor?

Yes, 2 BTS per motor. One was not enough, thermal sensor turned off them after a short time. Many people have problems with them because of little bad construction.
So I made some changes.
1. Resolder both 7960 chips with more tin what made better contact to circuit board in order to better temp flow.
2. Remove painting on the other side circuit board. See picture below.
IMPORTANT! this clean areas will touch to additional radiator but they have to stay electrically isolated. So you can use thermal pad which do not let current pass through.
3. Put thermal pads to 7960 chips and on the new cleaned areas and mount one radiator on chips side and the second on cleaned side. I have used same radiators demounted from other BTS where I bought few extra pieces and few other aluminium radiators which fits very good on the other side but they need some drill work to make place for nuts. you have to use also little longer bults which are enough to go through both radiators and circuit board.
So prepared BTS will work much more effective then the original one.
All of them which were prepared like that were connected parallel 2pcs per motor and work for me for almost a year now and no problems since then.

Thanks for the quick response! I am at the initial stage of construction and I have already had problems with shutdowns, so if this happens again, I will also try 2 bts per motor!

Thanks for the quick response! I am at the initial stage of construction and I have already had problems with shutdowns, so if this happens again, I will also try 2 bts per motor!

Hi, because few people asked about dimensions and planes of my construction. I am putting it here as soon as I make some measurements.

This is so very appreciated. I have started to draw your construction in Fusion360. I can share the model with the community when done if anyone is interested. Big thanks @Gabriel the simracer

It's still a work in progress but since a few people have DM me I decided I'd upload the latest version available here, it's Fusion 360 file. Can't post links so copy/paste it to the address bar and remove the spaces before and after com

drive.google. com /drive/folders/1TFb74d_ovhcX6OhpgPeHzRdBEi5rYNjZ?usp=sharing

I’m looking to start making this as a project as I have access to wheelchair motors and am an avid sim racing enthusiast, I was wondering what needs to be done with the arduino to set it up and if there is code available that could be used and altered for different motors?, and if anyone has some tip as I am reasonably new to a lot of these processes they would be appreciated, I’m going to learn how to mig weld after Christmas and am looking to get my hands on the steel from second hand sources to I am looking to get started on setting up in the software side to gauge feed ability with the motors I have, thank you.

Hello, it’s great to see you developing your passions!
Regarding Arduino, there’s a separate topic you should start with.
https://www.xsimulator.net/communit...3dof-motor-driver-and-windows-utilities.4957/

In short, the Arduino software is called SMC3, and it includes several modes. You’ll need to choose one that’s suitable for the driver you selected for your motors. After installing SMC3 on your Arduino, you’ll need to configure the settings for your motors using the SMC3 Windows Utilities program.

Once configured, you’ll need software to read telemetry from the game and send data to the Arduino. There are several options for this, such as Simtools, FlyPT Mover, Simhub, and Sim Racing Studio. FlyPT Mover is free but more complex, while Simhub offers a working demo version. The others are paid. From personal experience, I’d recommend starting with Simtools or Simhub for your first steps.

The most information and solutions to various problems can be found on forums, but it does require some time and a willingness to learn. Good luck with your project!

thank you, also i was wondering what torque your motors output?, I've found some 24 volt ones, but running them at 12 volts they produce 46Nm and they have a 20-1 ratio. I've definitely got a lot of research to do but i have a reasonable amount of time until i get hold of the materials,

I have Simhub for other things, but it will run the telemetry to the Arduino?

My motors come from Permobil wheelchairs. The motor models are CIM CM808-077A and CIM CM808-077B. They have a 26:1 gear ratio, are powered by 22VDC, and their power is either 300W or 350W—I don’t remember exactly. It’s hard to find more information about these motors online. DC motors have high torque at low RPMs and low torque at high RPMs.

As for SimHub, it works without any issues, but you need to activate the Motion function since it’s hidden by default and configure it with the settings for your Arduino.