Showroom DIY Budget Compact Build

I don't think it would make any difference. I am actually considering moving mine to the back if they cause any issues with getting into and out of the sim.

That's actually a good point. Mine is weighted towards the front even with the seat sitting a couple inches behind the u-joint. In the future I might try moving the seat back another notch to get the cg closer to zero.

Although for people who haven't read it yet, it is important to have it off balance of the cg somewhat to reduce the effects of the backlash in the motors. Essentially if you have it always positively or negatively weighted on the motors then you wont notice the play in the motors lever arm as it will always be compressed in a direction. More info here.

Thanks for the reply. I was wondering why it is so popular to have them in the front even though they will be more out of the way in the back. Just came to think about that one good reason to have them in the front is that if you have, or planning to have, traction loss then having them in the front leaves more space for the traction loss motor in the back.

For anyone interested in the pot mounts and couplers I used in my build, here is a link to the thread in the 3d printing section.



So far so good with these. The coupler is nice as I can still turn it by hand on top of the motor shaft to center the lever arm.

I have spent the past couple of days working on refining the sim to make it look better and add some extra functionality.

I first put all the electronics in a mini-itx pc case that I purchased off amazon. I 3d printed a sudo motherboard that I placed all the electronics on. The sabertooth was originally face down so that I could place a cpu watercooler on it, but I later decided to turn it around because it was too hard to connect wires. Here is a picture of the initial layup and the 1.5 ohm power resistor packs for each motor.




The board has two arduino nanos on it, one for SMC3 and another to control other fun stuff like LED's and LCD screens. I have 3 TMP36 temperature sensors to monitor the temps of the power supplies, bridge rectifiers and the sabertooth. The temperature information is displayed on a tiny OLED screen in the motherboard. I soldered the arduinos to a solderable breadboard with plugs so it is easy to change hardware and work on the electronics.



I then put it all in the pc case with a 200mm fan and two 80mm fans. The two power supplies fit nice in the case underneath the motherboard.



I opened up a cheap amazon USB hub and wired its input into the front USB ports on the mini itx PC case. I also made it powered by adding in a 5v regulator to the power lines in the USB. This setup allows me to connect all of my USB peripherals and arduiono's to the sim itself and then run one USB-A to USB-A cable from the sim to the PC running simtools. There's got to be a limit to the number of things you can send over one USB cable especially at USB 2.0, but so far I haven't had any issues with two sticks connected and two arduinos. SMC3 indicates its doing 1000 calcs/sec.



Finally I added addressable LED's and got it all powered on. It came out looking pretty sweet!



Since the LED's are addressable, I can do fun things with them like correlate the colors of the led lights to the temps of the components, which will be coming soon.

I was originally attaching the lever arm to the shaft by just tightening a nut and pinching the motor shaft as tight as possible. This kinda worked until a fast acceleration and it usually came loose.

I tried first fixing this by drilling a hole through the shaft and screwing a M4 bolt through it. This solved the problem for a good bit of use until the M4 bolt sheared. I needed something stronger so I went to lowes and found 1/8 inch pins that I am currently using and these have not failed me yet.



I purchased the warthog stick and center mounted it. I used 1 inch steel slotted tubing and 3d printed a baseplate for it.



I also added seat belts and platforms for the throttle and future peripherals to sit on. I printed a little stand for the Oculus touch controller so it doesn't slide off the platform when the sim moves. It is very convenient to use in X-plane with the clickable cockpit. I am still deciding what to do about the mouse situation, so I am using a tubaware container for now. I am thinking either a touch pad or trackball mouse.



Through tuning this rig, I noticed the backlash in the motors was really causing me issues. I fixed this by attaching bungee cords from the seat platform to the bottom frame. This pressure pulls the back of the sim down and it keeps it on one end of the backlash. This DRASTICALLY improved the experience and is definitely a must have. I tried many CG configurations but could never get the backlash completely out until I started using the bungee cords.

While at it with the bungees I tried attaching them to the shoulder harnesses for the seat belts to act as seat belt tensioners when the seat tilts forward. This simulates decelerating by giving you the feeling of falling into your seat belts. It actually worked out great and adds to the immersion, so I will be keeping it.

Here is the most recent video of it in action playing X-plane 11.

So I ran out of the original 3 usb ports I had on my sim, so I purchased another usb hub and added another 3. This is what the new backplate looks like now.



I now have 7 usb ports running through one usb-a to usb-a cable to my main pc running simtools. It is a very clean setup.

I also looked into making my own switch box. I 3d printed the box out of pla and used 2 and 3 position switches as well as push buttons. The interface was incredibly easy using a zero delay arcade usb encoder. These allow up to 14 inputs that can be directly wired to switches and buttons. I used joystick gremlin to create a virtual joystick (vjoy) which in turn allowed me to use toggle switches to send pulses for both the on and off position.



I 3d printed switch caps to go ontop of the toggle switches so that they mimic the switches in the cockpit as well as are easier to find when in VR.

Wow!!!!
So many great ideas combined into this rig.

3D printing a mock mobo for that mini ITX case is brilliant, as are many of the other ideas and accessories!
Very inspirational, it's causing me to want to go and pull my rig apart and refine a lot of the hardware in order to pretty it up.
Definitely keeping my eye on your rig and it's progress...GREAT JOB!!!!!!

I powered on my sim today and the motors weren't moving. Upon further investigation, it turns out I bricked the Arduino running the SMC3 sketch. I tried uploading a new bootloader with a usbasp programmer with no luck. Unfortunately, I direct soldered everything on the PCB so an arduino switch will be a lot of work. Currently took it all apart and am working on creating a new sudo motherboard that will only feature one Arduino to run the SMC3 sketch modified to run only LEDs. I am getting rid of the OLED screen and temperature monitoring in this revision as it wasn't very useful last time. More pics to come.

Weirdly enough the bricking of the Arduino happened immediately after plugging in my sim to the computer after updating to simtools 2.4. Probably a coincidence, but has anybody else experienced anything simular?