Adding 2DOF (Seat Shaker) to Aluminum Rig

New part in the mail today, 80 amp battery isolator.

I will use this to disconnect my battery from the sabertooth, I don't want my sabertooth pulling power from the battery when I'm not using the sim and killing the battery. It is essentially a large relay that operates on 12v.

Paid about $18 with shipping on eBay, I will 3D print a mounting bracket and mount it on my din rail.

Sweet, look forward to seeing this box all complete...shame you didn't have a plexi lid or something to show it off.

i was able to print a simple bracket and mount the battery isolation relay.



It fits about perfect

So I have been sharing time between this project and my DIY linear actuator, but for some reason I really got the itch to get this going so I can start using it. Maybe its because I just got another renewal notice from Iracing, It's been 3 months since I last renewed already and I didn't even use it.


Anyways, one of the last things I needed to sort out for the control box before wiring was the relay assembly. I need 14 relays in total so I ended up with 2 8 channel relays designed for an arduino.



I wanted an easy way to connect everything so I found a breakout board for an arduino micro and figured I could wire the breakout to each relay and use the breakout board as the terminal connection for each relay. I also picked up an assortment of ribbon cables with different combinations of male/female ends.



To use the breakout board as a pass-through connection I soldered up a custom PCB that just has jumpers between the pins.


Then I test fit the board to my 3d printed relay box. More 2-56 screws, they literally disappear when you drop them.



Then I wired everything up and grabbed a 5v supply to do some testing.




This is where things got interesting, I had made an assumption on how the relays worked that was wrong. My switches are wired to provide 5v out when turned on, I assumed that the relay module would turn on when 5 volts is applied at an input, not so much. turns out this thing is wired for ground, so the relays only turn on when the input is pulled to ground. That's a bit of a problem as I cant change the way my switches work or else they wont light up. So I thought about it for a while and decided to just hack up the relay board.

All of the components on the relay board are meant to protect the micro-controller, but I'm not using a micro-controller so I just bypassed everything. I decided it would be easiest to run jumpers from each input to the coil of the corresponding relay and then tie the other side of the coil back to the ground pin. I essentially bypassed all of the circuitry and am directly wired to the relay coils now. I hate stripping/soldering jumper wires so I just grab some resistors and clip the leads off them. This is what I ended up with.



I did another test and all turned out just right, but I wasn't happy with my relay box. It was just a little too easy for the relay boards to slide around and there wasn't enough space for the wires to pass through. So I decided to tweak the design and print another one. It turned out pretty well, but the printer head knocked one of the corners off during printing leaving a gap.



Not a problem, I grabbed my trusty wireless soldering iron and a bit of filament and went to work welding fixing the issue. It turned out pretty good and I think it could be a viable option for mating printed parts for larger assemblies.



So here is the final assembly tested and ready for installation.





My only gripe would be that I designed the mounting holes inside the box, that means that when I bolt it down I need to remove everything. Not a big deal, but if i were to do it again I would add the mounting points on the outside.

Also, I was planning on using an arduino for the relay that turns my computer on and off, but now that I have hacked up the relay boards I will have to come up with another solution.

So here is my solution to the arduino-relay problem, I decided to grab a spare breakout board and build my own relay circuit right on the arduino uno. I was height restricted so I had to turn the relay on its side and kind of build the circuit in the air.



Now I have pin D0 directly connected to the relay so I can tun on/off the PC without risk of damaging the arduino. Here is the uno with the megamoto plus on top, can't even tell the relay is in there and I get terminal blocks for all of my connections.



I also thew together my relay pcb for inside the computer. I had designed this pcb a while back and had it made at OSHPARK. Its really small, so it only cost about $3 for 3 boards.

USB +/- connect to an open usb header, only the +and - terminals matter here, this is where the relay gets power when the pc is turned on
PWRC - this is were the case power switch will now connect
PWRM - this connects to the motherboard power header
STAT - this is the Normaly Open pins of the relay
PWRO - this is connected in parallel with the PWRM and PWRC connection.





I am using a 4 pin 2.5mm audio connector for my connection from my pc to my control box. I picked up 5 of them on ebay along with a cable for next to nothing (except it took 2 months to arrive). I mounted the audio jack on a pci cover.



I just used some double sided tape to stick the relay inside the PC and then used jumper wires to connect everything up.



So the concept is this, I have a switch on the control panel that will turn the pc on and off. I can't directly connect that switch to the pc because it is a maintained switch so I have that switch turning a relay on/off. The relay is read by the arduino and the arduino will control the pc to match the status of the switch. The arduino does this by toggling its on-board relay which is directly connected the the pc power switch, then the relay inside the pc will turn on and off with the pc which is fed back to the arduino so it can determine the status of the pc. Its a bit more complicated then it needs to be, but the use of relays helps isolate the arduino from the pc, its not completely isolated, but way better then directly connecting the pc to the arduino. Also I can still use the power switch on the case to turn the PC on and off if needed.

The Idea is that I want to be able to turn my whole rig on and back off from the cockpit, kind of like a real race car would be.

I finally got a change to mount everything into the control box, luckily I remembered before hand that I needed to add a couple of feet to the box. The feet nest in some pockets on my rig and will keep the box from sliding around during use.



Here is everything mounted and ready for wiring.







The battery is mounted with the new brackets, I installed covers on both USB hubs and I even added some wires to the power supplies because they are in a location that will be pretty tough to get to for soldering from here on out. hopefully I will get some time this week yet to start wiring.

Finished all the wiring, not the prettiest box I have built, but it will get the job done. there are some very hard to reach places in there.













For the most part i was testing what I could as I wired, and everything seemed to be working as expected in the garage where I was doing the wiring.

Here is the box all setup ready for testing on the rig, eventually all of this stuff will get put underneath the rig. (the control box is really heavy, 50lb+ probably)



It was about 12 am when I finished and I wanted to quick test the direct drive wheel and go to bed, then I ran into a couple of stupid problems that took me about an hour to figure out. I had removed my servo cables from the servo motor itself, but forgot and didn't check them so I spent a good 30 minutes trying to figure out if I miswired the argon servo drive before I realized my mistake. Then I couldn't get the discovery board to show up in windows, so I tried about 6 different cables thinking maybe I had a charging only cable (no data pins) but no luck. I was actually on my phone getting ready to order another board and noticed a few jumpers on the sales photo of the discovery board. I looked and sure enough I was missing a jumper, I replaced it and everything is working again. So after a few months I was finally able to do a couple laps in Iracing (finally got to try out dirt!).

Now I will start working on the wiring for the motors and fans and continue testing in this configuration until I get everything just right.

Congrats! It's beautiful!

Also, in edit, you and Avenga76 were the push I needed to get a 3D printer. Just excellent work and great examples of the ways you can solve problems with them.

Thanks, the wires are flying all over the place right now. Once I get it all working I will tidy up the outside wiring and it should look pretty slick. I'm just happy I get to do some racing in the mean time.

And I'm Back!
Hard to believe its been 4 months since I last worked on the racing simulator. My linear actuator project is starting to wind down and I have been getting the itch to actually use my simulator so I will be putting some actual effort into finishing it in the coming months.

Things to do
New Seat, my current seat is a cheapo vinyl one that makes me sweat just thinking about it. any suggestions?
Finish wiring motors and tuning motion
Add wind generator fans and program
rebuild PC with fresh copy of windows (I keep getting errors from all the junk that was on the pc when it was re-purposed)
Add a lock-out for motion so when I don't want it on the seat doesn't move.
Add my 8 Transducers back to the rig (4 corners, 2 under seat, 1 under pedals, 1 Wheel or shifter)
Mount my shifter and Emergency Brake
Main power switch/Disconnect
Move all electrical boxes into the frame and clean up wiring
Find a way to mount monitors so they don't vibrate as much (V8 stock car really gets them humming at idle)
Program Tablets for typical controls and dashboard display
Permanent mount a keyboard and mouse
Grab bar to to assist entry and exit of the rig


Lots to do and never enough time

I got the rig mostly re-assembled, It has been in a sort of storage state for the last few months. I am just amazed at how many cables are needed to get everything connected.The side monitors have been re-installed, Switch box is mounted, New Keyboard/mouse combo setup (logitech K400). Tablets are setup and operate off the switch panel. I was able to put the 4 corner transducers back on with a new offset mounting method, I have about 1/4" of clearance between the motion system and the rear transducers. Next on the project list is to get the remaining 4 transducers installed and get simvibe working again.









I spent the better part of a day updating software and drivers only to find out that a clean install would have served me better. I can't get iracing to run on all 3 screens in full screen mode and even in windowed mode I am only getting about 15fps. The tablets software was updated on both the pc and the tablets and I am happy to report that the tiny bit of lag that I used to have is gone now. I am planning on getting the remaining 4 traducers mounted and get simvibe tested before I attempt a full re-install of windows.

I haven't been taking as many pictures because I am mostly doing software stuff at this point, but here is a little update. I ended re-formatting the racing pc and re-installing all of my software. so far everything seems to be playing together nicely. I have the 4 original transducers working in simvibe, I still need to mount up the remaining 4. I was finally able to install my E-brake, and good thing too because iracing now includes rally racing. I also setup all of the tablet dashboard software so now I have functioning readouts and button boxes on each of the three tablets.



I started working on the motion portion of the rig again, really only needing to connect everything and start playing around with simtools. I even designed some beefy plastic stops to keep the motor arms from destroying my potentiometers. I also finally changed out my 3d printed arms to the aluminum ones that I have had for nearly a year now.




however, It has been so long that I couldn't figure out which version of the XPID software my arduino was running and when I re-loaded the stock version everything went to hell. long story short I smashed all kinds of stuff, including my first version of the stop blocks and bent the shaft on my potentiometer. The motor ended up drive full power in one direction until something gave. I though I had just broken a my 3d printed part, but turns out I had sheared off the bolt/pin that keeps my arm mated to the shaft.






I got everything all fixed up and put back together as best I could, but realized that I had damaged my gearmotor to some extend. It is now making a lot of noise, more in one direction then the other but it is very noticeable. so I took everything apart again and took a look, no noticeable damage on either the gearbox or the motor, however I can hear the brushes clicking as the motor rotates so it seems like something got damaged during the crash. Here is what the inside of my 50:1 gearbox looks like.



I am still playing with the XPID software and trying to figure out what I had changed to suit my needs. I know it was working great before I put everything away nearly a year ago. I now have almost everything working as intended I just need to setup the blower fans and get my pc on off switch working, both of those should be relatively easy, this is what I am thinking for my blower fans as I am limited on where I can place them.

I was just gonna say, Smart idea On the mechanical stops, but no 3d printed part will withstand a Run away motor with these torque levels.

Nice update bud.

Wheel deck looks great. can i suggest some cam clamps to get some adjust ability in the mount ?

The stop that broke was a prototype at 10% fill, so I never expected it too last. In fact I wasn't even supposed to be testing with the prototype on there because I knew it would break, but you know how it goes. The new ones are printed nearly solid and have already survived a handful of runaways, the final versions will actually have a bolt running through so the stress will be on the bolt.
Adjustable wheel deck was always the plan, but its so heavy now that It would be pretty difficult to adjust. Maybe in the future though.

Ah, Yes a Solid part would be much stronger with layer delam dept with how you have those. Good to know it'll survive a direct hit from the motor's.

May i inquire where your getting the Runaways from ?

Have a think about some cheap Gas struts to support the wheel deck so make adjusting easier.

Runaways were from setting up the software, having things wrong etc. I'm not expecting there to be any runaway issues once everything is tuned but you never know.

Still working on the software side of things, but I'm getting very close now. I put the XPID software aside for now and switched over the the already proven SMC-3. I still need to do tuning, but it appears to be working well enough. (Once I have time I hope to get back to the XPID code) One of the last items on the list is to setup the wind generators, I have a bit of a unique situation as I am using a Mega Moto Plus motor controller vs the Monster Moto version that everyone else commonly uses. I just happened to have one laying around so I figured why not utilize it. I read through the forum topic and took a look at the code @SilentChill put together, it looked simple enough to modify for my purposes so I pulled out everything that wasn't needed and rebuilt to suit the Mega Moto. I am not a programmer, but I have enough experience I can usually fumble my way through given enough time and plenty of google searches. I discovered a really cool arduino simulator on tinkercad that allowed me to write all the code required for the mega moto and actually test the serial commands right in my web browser.

Here is a link to my test code within the simulator - https://www.tinkercad.com/things/4xxRB8A56AP
If you want to play around with it, just open up the serial monitor and start typing commands in the form S000, I have the input range from S000 to S200.



So I loaded up my code on my arduino and set to testing out the fan using serial commands. It actually worked on the first try, but the fan made some nasty noises at the lower end of the range and it sounded as though it was really struggling. being that the arduino pwm output isn't actually an analog signal but a pulsed digital one I was hearing the effects of a too low a pulse rate. My mega moto is capable of 20khz signal processing which would put any fan noise at the edge or outside of the normal hearing range. so I pulled out my o-scope and took a look at the existing signal.



my stock arduino uno using timer1 on pins 9 and 10 runs at about 490hz, I set out to get that up to 20khz. So a bunch of googling around and I found a lot of information that was over my head and one very nice post with exactly what I needed. So I added a little snip of code and it increased the pwm speed to 20khz. I had to change my pwm scale from 0-255 to 0-400 to get full range of output which is all handled with the scale command in the code. Here is the result



I am also using this same arduino to turn on my pc through some relays and inputs so I wrote a little bit of code to accomplish all of this too. now I am ready to get my fans wired up and start testing gamedash.

I know this code is pretty specific to my needs, but I will share it just in case.

big thanks to @SilentChill for the base code which was my starting point.

I have also been working on the air ducts for the fans, I ended up having to model everything in fusion because my normal software (alibre) just kept crashing. even fusion was having a tough time with the loft and shell calculations. Here is my first prototype ready for 3d printing. I will be printing in two halves and then gluing the halves together, I added tabs for bolts so that I can secure everything while gluing. there will be two unique versions of the duct printed in 2 parts each for a total of 4 unique parts.














I have the first versions printing right now and should have some prototypes to test out soon, I will need to raise my monitors up by about 1" to fit this in. That will probably be a two person job if I don't remove the monitors before hand. I have also been on the lookout for black 4" flex vent which so far has been difficult to track down locally.

I have been working on the tablet dashboard software a little bit and seem to have everything working as expected, but I wanted to share with everyone another really cool group of software that I am using. Its called the Digital Race Engineer and it is basically a voice command race manager for Iracing. it allows you to do everything you normally use buttons for with your voice. Its actually a combination of a few pieces of software.

Voice Attack - https://voiceattack.com/
this is the basic voice command software that allows you to make voice commands for just about any function in windows.

Digital Race Engineer - https://theawe.dk/product/dre/
This is a plugin for voice attack that already has hundreds of commands written to interface with iracing

Ivona Brian Voice - http://www.deskshare.com/text-to-speech-voices.aspx

joytokey - https://joytokey.net/en/

I had to create a keymap for iracing to make sure that I had all of my keymaps for the DRE and for the dashboard software setup correctly. it was a pain, but its done and I have attached it for anyone that may need it for future use. iracing has about 180 different inputs not including the actual driving controls. I have all of my inputs setup as keystrokes and then use joytokey to emulate keystrokes with my wheel so that I can use either my wheel or my dashboard (buttonbox) or DRE for the same input.

I'm mostly using the standard DRE commands, but I have created a few of my own to do things like launch iracing, simvibe etc. its pretty cool to be able to say "reset" in iracing or "exit car" rather then hold the exit button. also I can see how this would make all the difference in VR which I will be jumping back into eventually. of course this is specific to iracing, but it could be used as simple voice command for other sim software.

I invested about $60-$70 for all the software, but it was well worth the investment in my opinion.

https://www.dropbox.com/s/jmvu54w8d5yjje2/Iracing Button Map.xlsx?dl=0

@Hoddem - @Avenga76 put some chokes on the power wires to the fan motors to cut down spikes from back EMF. At 20 kHz, you might get some significant heating from it. It is much nicer to run at higher PWM frequencies though. He has details over at isrtv.com.

http://www.isrtv.com/forums/topic/23039-my-diy-wind-simulator/

I wasn't able to find the details (might be in the wind thread here) he posted on the chokes with scope traces and whatnot, but the chokes do indeed make a difference. It's why I decided to put high current toroids in my motor wires.

Love the ducts! Those are beautiful!