Hoddem's Aluminum Rig V2 (3-DOF, SFX, VR)

Thanks man!

I have to say though, when I found out my OSW was fried I definitely went through the 5 stages of grief.

This does turn out to be a happy ending though, more details coming soon.

All right, so I walked away from my rig in defeat on June 9th thinking I would be back at it that weekend. Fast forward 3 months and I get an email from iracing saying my 3 month subscription is ending. So 3 whole months since I brought the simulator out to the garage and not a single lap turned. I was now re-motivated to get this thing running.

First issue was the dead usb hub, I was able to test each component one by one and determine that nothing was actually damaged. The downside was that I had assumed my MMOS Discovery board was toast and in an attempt to recover it I re-flashed it meaning that I lost all of my wheel settings. I spent a while going back through all the original OSW threads and finding settings that seem close to mine.

Second Issue, I have an Arduino setup to trigger a relay that turns on my PC when I flip a switch. in turn the pc then turns on a second relay that tells the Arduino the pc is on. This allows me to flip a switch to turn the pc on, but not worry about accidentally shutting it down with the same switch. The whole system was essentially not working and after a lot of troubleshooting It ended up being that my PC bios was changed at some point and now the pc was powering USB ports even when powered off. this was turning on the status relay and keeping the Arduino from cycling the relay to start the pc.

Third issue, I was running my wind generators off of a mega moto plus, which isn't a common setup. I just happened to have one laying around so I figured why not. A while back I picked up a Sabertooth 2x12 controller thinking it would be a much better and easier implementation. I was mostly looking at the sabertooth because it has 35khz switching frequency and the mega moto after direct port manipulation with an arduino was supposedly 20khz. My fans always made strange noises on speed changes though and I though the sabertooth might fix that. So I pulled my mega moto out and dropped in the sabertooth.



My plan was to send serial commands to the sabertooth per the manual 0-127 for channel 1 and 128-255 for channel 2. after a lot of struggling I ended up settling for both of my fans wired on channel one because no matter what values I sent both channels were being driven. After talking with Dimension Engineering they said the arduino has known issues with sending serial communications to the sabertooth and that their library must be used. Either way I had working wind generators again.

Fourth Issue, I have a Pyle 8 Channel amplifier and 8x transducers. It seemed like no matter what configuration I wired the amplifier up I could not get more than one or two transducers to work. I eventually pulled my amplifier apart expecting to find burnt components, but found nothing.




After more investigation I found that the switches on the main panel didn't seem to be working correctly.



I disassembled the amp even further to be able to work on the input/output circuit board.



What I found was that the switches for selecting BUS/AUX/LINE and R/R+L/L were Double Pole Triple Throw switches and not all of the contacts were working when switched. I could wiggle the switch around and make them work, but they were unreliable. I ended up soldering jumpers on the back of each switch essentially locking the switch in the correct position. I also snapped off the actual switch so I cant accidentally change it later.



I had all of my transducers working on the first try after I fixed the switches.

With all of my issues fixed I set out to wire everything up in a more usable manner.

Just a quick overview of everything that needed to be wired.
Power - PC, Monitor, Amplifier, 3x Servo Drives
USB - Monitor, Pedal, Wheel, Shifer, Ebrake, AMC-AASD115, Stream Deck, Oculus Sensor x2, Oculus Headset, OSW Discovery Board, Wind Generator Arduino, Keyboard, Wireless Internet
Video - Monitor, Oculus
Audio - Amplifier x 2
Speaker Wire - Transducer x 4
Servo - Actuator x3, OSW
Custom - Switch Panel x 2RJ45

Im sure I am missing a few things, but without my USB hub I almost maxed out my computer and I have 11 extra usb3 ports through expansion cards.

I spend an entire evening updating all of the software on my pc, windows, simtools, iracing, simcommander, voice attack, etc.

And after a few evenings of testing and adjusting I was finally able to turn laps in iracing.

Here is where I am at now.

And I thought I had too many cables... Anyway, awesome setup

Very inspirational build and as far as cables go I do not think it looks all that bad. I really like the cover is that from a motorcycle?

Yes, The cable management is atrocious! I have big plans still, but I wanted to put the entire system through its paces before I start finalizing everything. Ultimately I Will have the entire Rig on that 4x6 mat with only one single power plug required to get it going.

Lets just say I will be moving on up!

Trust me, cable management will be a priority down the road, I will end up with an extremely clean build when I am done testing everything.

The cover is actually a UTV cover
amazon.com/gp/product/B006JMK48G

It is a little big, but my old rig was taller so I needed something that could accommodate the height.

Being that its in the garage, dust is going to be an issue. Also I find that my kids are less likely to climb all over it when the cover is on it.

@Thanos, I wanted to give a big shout out to you and thank you for the work you have done on the AMC-AASD115A controller. I have tried several motion control systems over the past few years and this has been the easiest to get going by far. I started with 3 brand new drives and a brand new controller and within 20 minutes I had everything setup and communicating with simtools. I was even further amazed that the very first time I did a lap in iracing everything actually worked. I cannot compare to the original SFX controller, but I am really happy with my AMC-AASD115A controller.

Well I got a little time last night to run some laps and I figured why not take a video. Keep in mind, I have not done any tuning on the motion beyond entering the values provided by @Thanos on the @LukeBrown thread.
https://www.xsimulator.net/community/threads/pt-actuators-3dof-system.13568/#post-181258

Here is my first concept for the base of the simulator, I was trying to decide between an elevated platform or inverting the actuators and moving the attachment point up. I really like the inverted actuator design because it is so unique and gets the pivot point much higher on the rig. That should help with any CG/Tip issues.







One thing I will have to accommodate is that the distance between the pivot point will change as the angle of the rig changes.

@cfischer has a good drawing showing what I am talking about in this thread here.
https://www.xsimulator.net/communit...actuator-and-using-4th-motor-for-surge.14793/

I have a couple of ideas right off the bat. I could 3d print a tpu insert for a cup that the ball of the actuator rides in and hope that I can get enough flex to accommodate the change. Right now I am calculating about 0.125" side to side and about 0.25" front to back.

Another Idea is to lock the front actuator in both the X&Y axis, then constrain one back actuator in the Y axis only and leave the 3rd actuator floating. That would allow everything to expand and contract as needed, There would be a slight offset movement to the rig as it goes through the motion, but again its 0.125" and 0.25" so it probably wouldn't be noticeable.




Here is the way I could constrain the rear actuator, the front would just be a full cup.



Ultimately I want everything tucked underneath so that I can keep the entire simulator to the 4x6 mat. The concept above would push the top of the frame rail to about 20" in the down position and 24" in the up position. I would have an electronics box of 62"x26"x9".


My last rig was pretty clean when it was all done, I expect this one to be even better.

Need a little help understanding the way my rig is supposed to react. I followed the axis setup guide but I am still confused about surge and sway.

I’m the output testing tab I have the following
Roll slider to the right rig rolls right.
Pitch slider to the right rig pitches forward
Heave slider to the right the rig lifts up
Sway slider to the right the rig rolls right.
Surge slider to the right the rig pitches forward.

So right now surge and sway go the same direction as pitch and roll on the sliders and should go opposite direction in game.

This is why I am confused. If I am thinking about acceleration. If surge pitches the rig forward you would get pressure on your back initial but then lose it as you reach full pitch. If surge pitches the rig backwards the initial movement relieves pressure on your back but can then hold sustained pressure once it has reached full pitch back.


I’m in the mindset that the simulated sustained force is what we are after. I guess I need to know which direction the rig should pitch during acceleration from surge only. Same with sway in a right hand turn which direction should the rig roll on sway only.

appreciate any help on this.

Maybe this will give you some inspiration .

HAHA, that looks like the last thing I need. Next thing you know I will be tearing everything back apart if I watch too many videos like that.

Nice, inverted actuators for the win. I vote for the cup idea.

Good luck getting the feeling of sustained forces with chassis motion. On my pegleg rig I greatly preferred only counting on high frequency data coming through the chassis.

imho low frequency is best left to pressure based systems like gseats and belts.

I will keep it short to not pollute the thread, but it looks very similar to my new sim, but without the actuator drive rods - everything therefore sits allot lower. G systems will be re-fitted .

mannn all i gotta say is this is awesome! job well done!!

im about to embark on my own sfx journey and i cant wait! but yours is mind blowing! hope your having a ton of fun mate!

lots of progress over the last month plus, I was determined to get build a control box and invert my actuators.

Here is the final design, it is still in draft format.


I scavenged up what I could of my remaining aluminum and started to dissect it into the required sizes.



I only had to make a few cuts so I just set my saw on the ground and went to it.



After cutting ready for drilling and tapping.



terrible picture, but I drilled what seemed like a thousand access holes and then tapped the ends of all the aluminum. this was the resulting mess.



Because these pieces were so long I tried something different this time for cleaning. I grabbed my kids pool and gave them a wash. It was only about 30 degrees out at the time and I decided that would be the last time I go that route.



Not long after I finished the first batch, the new aluminum that I ordered showed up. This is everything needed to build the box and invert the actuators.



No cutting this time, but again I had to drill a lot of access holes and tap all the ends.




After hours of drilling and tapping, disaster struck. I was on my second to last tapped hole and I broke the tap. I can count on one hand how many times I have been able to recover after breaking a tap, but after a lot of fiddling I was able to recover. I ended up using a dremel to grind a slot in the tap and then used a flat screwdriver to work the tap back and forth until I eventually got it out. I had to use my impact drill to initially get the tap to break free.




Back to the old method of washing.





Everything is prepped and ready for assembly.

This is all the aluminum for the box


This is what will be added to the rig.

Assembly time, I made sure to keep everything as square as possible and because I am using all hidden fasteners I needed to really plan ahead to not build myself into an impossible situation.



Added all of the mounting points for the bottom panel as well as all of the t-nuts for future assembly of the panels and the actuators.





Next up were the panels, I used 1/2" plywood.



This was right around October 31st and my kids thought for sure it was a coffin for Halloween.



After the initial test fit the panels came back out to be drilled and patterns cut for fans, power cords etc.
It was at this time that I also lugged the base from the basement to the garage, my back is still not happy with me on that one.

Here is one panel all laid out ready to be drilled and cut out.



Another round of test fits, frame is up on rollers now to make things a little easier to manage.





Everything looked good, so I threw on a coat of paint.



Final assembly, here is a little trick I use for stuff like this. I thread nylon studs into the t-nuts and then set the panel in place. This allows me to get everything lined up correctly and then pull each stud out one at a time and replace it with a bolt. This process makes a normally impossible task pretty slick.



Missed a few pictures here, but I added some AC infinity fans and the main power switch to the box. I also added handles to the lids and the lids are magnetically attached so when I want to remove them I just lift up and they pop right off.



Tucked away until i'm ready to put the actuators on.