The SimFeedback-AC DIY Motion Simulator thread

sjb266 · Sep 17, 2018

Hey guys. Thought I’d create a thread for those taking the plunge into this brilliant DIY project..
I will be starting mine soon and I know there are others thinking about it.. so feel free to share your knowledge and experiences so we can all enjoy this platform to its full potential. A huge thanks to the developers who have really knocked this one out of the park!

Website: https://opensfx.com/2019/02/20/welcome-to-our-new-site/

Github: https://github.com/SimFeedback/SimFeedback-AC-Servo/wiki

For all the internals for the actuator contact Amy - skye@ntl-bearing.com
She can supply everything you need. Just remind her you want the ends of the shafts chamfered and make sure she sends the right sized ball screw - we have had a couple of issues reported. She is very helpful though and the cost is pretty good.

Huge thanks to @RowanH for writing a comprehensive user guide which can be accessed here - https://www.rowanhick.com/sfx-100-build-and-running-guide

In addition, @anton_Chez has contributed a list of post numbers for some of the important settings etc..
Post #320 SFX-100 thread
Post #327 SFX-100 thread for Discord correlation
Post #339 SFX-100 thread
Post #418 SFX-100 thread
Post #424 SFX-100 thread
Post #439 SFX-100 thread
Post #449 SFX-100 thread
Post #517 SFX-100 thread
Post #554 SFX-100 thread
Post #580 SFX-100 thread
Post #826 SFX-100 thread
Post #837 SFX-100 thread
Post #864,866,867,868,870,887,889,897 SFX-100 thread
Post #911,914 SFX-100 thread
Post #988,992,998 SFX-100 thread
Post #1147 SFX-100 thread
Post #1492 SFX-100 thread
Post #1511,1517 SFX-100 thread

I will try to keep this page updated with links to source the parts in other parts of the world. Just post whatever links you have and i'll add them here.

Please note: Not all the parts listed below are essential for the project. For the essential parts refer to the original shopping list.

Australia:

Thanks to @AussieSim for the following links:

10A power lead(s) * 4
https://www.jaycar.com.au/2m-black-mains-extension-lead/p/PS4152

Top quality wire stripper
https://sydneytools.com.au/product/boxo-cutws205-multifunction-wire-stripper

RCD/safety switch power block
https://www.bunnings.com.au/arlec-4-outlet-heavy-duty-portable-safety-switch_p4420028

WD-40 lithium grease for the ball screws
https://www.bunnings.com.au/wd-40-specialist-300g-high-performance-white-lithium-grease_p6100408

Vibration pads
https://www.bunnings.com.au/whites-on-site-100-x-12-5mm-rubber-anti-vibration-mat-4-pack_p3961547

WD-40 Dry PTFE spray for the slider (free shipping)
https://au.rs-online.com/mobile/p/lubricants/7577134/

Arduino Leonardo (free shipping + frequent 10-15% off discount)
https://www.arrow.com/en/products/a000057/arduino-corporation

DB25 cables * 4 (free shipping)
https://www.arrow.com/en/products/ak401-2/assmann-wsw-components-inc

PETG * 3 (free shipping)
https://www.arrow.com/en/products/petg17bk1/mg-chemicals

WAGO-like connectors to avoid a breadboard (perhaps use genuine ones if you are doing 240V AC)
https://www.aliexpress.com/item/32906719488.html

D-Sub breakout boards * 4
https://www.aliexpress.com/item/32297675967.html

3D printer Creality Ender-3 Pro
https://www.aliexpress.com/item/32918302452.html

Wires from Arduino to D-Sub breakout (remove black plastic from the WAGO end)
https://www.aliexpress.com/item/32887680826.html

Crimp connectors for AC wire leads
https://www.aliexpress.com/item/32813550981.html

anton_Chez · Jan 9, 2019

Images work fine here but they cannot be too big otherwise the site rejects it. I just use Resize @ 40% in good old MS Paint to get them down to an acceptable level.

@sjb266 @Steve D My Arduino is the same one from the link in the OP. I am pretty sure I just ordered the exact one. I have no idea as I didn't know what I was looking at when piecing together the shopping list in the first place. I am going to run through the tests today to hopefully pinpoint what is going on. It seems incredibly fussy even though I had a test run going for 2+ hours with all motors running. However this was directly connected to the PC with a 1 - 1.5 meter cable at most. No hubs or extension cables. I've got USBView which is handy but slightly confusing. I only connected the Arduino to the hub, the only reason I have it is to provide a powered option otherwise I'd just use another extension cable as I have a spare port or two remaining.

Where can I get a genuine board from then in the even I need to replace mine? I'd love to go an pick on up locally. I might see if Jaycar has them. I'll report back and hit the Discord up as well since I've finally organised all of that.

sjb266 · Jan 9, 2019

I don't think Jaycar sell genuine Arduino and the one's they do sell are hideously expensive..

anton_Chez · Jan 9, 2019

On the topic of prints, mine to the touch are absolutely perfect. I've NO experience in 3D printing but as a noob looking at them they feel solid as a rock and every edge is perfectly refined and hard. No warping anywhere. Some of the parts were very snug but I managed to get everything where it needed to be with a little coaxing. I guess once it's all done you'd rather everything be a little on the tight side so that nothing moves but getting everything together can be frustrating. I say my prints, when in fact they are not mine but Simon's handy work. I think that out of everyone here I've had the least labour intensive and time consuming build to date. Outsourcing two weeks of flat out printing plus the time to learn has been extremely cost effective. Once again, thank you @sjb266. Funny thing is in the wiki it says that the threaded inserts are the trickiest part. I could have done 1000 of them yesterday and enjoyed every drill trigger pull. They were SO easy to put in. I used a variation of Hugo's method. My 150mm drill bits that I use for work have a hex shank, so I just slide that all the way into the slot and drilled the insert with the chuck of the drill up against it. This allowed me to keep them pretty perfectly straight as they went in, all with what I use for work every day. A little drop of bike chain lube aka dry PTFE made it so painless.

I seem to have response in AC now. Just testing a few different configs regarding USB connection and then hopefully can settle on what works best. I have re flashed the Arduino and I am not sure if this has had an effect but since I did it, it's worked properly. I also changed connections so this might have done the trick but something has improved I just have to work out what it was. I am also curious to see if this powered hub gives me any more success in extending the Rift cables. Will test that out too.

sjb266 · Jan 9, 2019

I know it sounds really obvious.. and I don't mean offence.. but just make sure the estop is not engaged.. and that you reselect the com port in setup tab every time you change the USB input..

It has caught me out!

anton_Chez · Jan 9, 2019

Yes that must have caught people out for sure by now. I've done the same thing disconnecting a piece of hardware like a shifter or something and then going mad wondering why I cannot bind it, forgetting to plug it back in later. Checking connections should be the first item on the list in troubleshooting.

So a little update and something others might find interesting or helpful if they end up with the same issue as me. I used the info that the front USB 2.0 port always worked as a guideline. I found a couple of little extensions lying around and joined them together, obviously not a great idea but something at least that allows me to test without destroying my current cable 'management'. Using these I plugged the powered hub into the rear 2.0 slot, of which I have only 2. Normally reserve these for just mouse and keyboard and let everything else use 3.0. Well it's been running AC for around 15 minutes, not a drama, so far. Nothing is connected to the hub other than the Arduino but I plan to test extending the Rift with it, too. I was able to Start, Stop not a problem, no freezing up or dropping out.

My take on it is this. My particular board HATES USB 3.0. It's strange but I kind of got lucky that I mistook my hub for a 3.0 when in fact it was a 2.0. I of course need to run it more but I think that USB 2.0 is required for my Arduino to be consistent. I could be wrong and other things might be at play here but it's awfully coincidental that whenever I use a 2.0 port, whether it's with an extension, a hub, BOTH, or directly into the front port with the Arduino's own cable not longer than a meter, it doesn't matter. It all works. 2.0 seems to be the key.

anton_Chez · Jan 9, 2019

Now that I've seen it running, I have another thing to work out. I see that sometimes the feet of the actuators come away from the floor. I am only using 1200rpm so far so nothing crazy. I am not sure how high I am supposed to have the intensity in the profile but I just moved it up enough so that I could confirm everything is moving properly.

Is there sort of a level calibration that the software has that I've missed? Similar to how the V3 allows you to offset any mounting errors with the level offset setting? How do the actuators interpret each others relative position to each other, at least on start up or through an initial configuration? Maybe intensity is too high? Or maybe since I just followed the wiki regarding the motor and coupling attachment there is some slippage? I didn't do the sanding filing thing that some have. Couldn't be bothered.

I've pushed all the actuator shafts right down to the minimum height and plan to do a few laps with me in it. See if it makes a difference. I don't think there is slippage but I can't rule it out. Some of the couplings I had to smash on so I can't see them coming loose. Front left actuator seems to be the biggest culprit however I have noticed that there is every so slight movement off my vibration pads on one or two others. The front left I was actually able to move the pad while the AI was driving, to give an indication on how much lifting there is.

We're nearly there! Just some minor tweaks now barring anything I've already solved cropping up again.

If anyone has trouble with this build, just search for my name in here. You could copy paste that into the troubleshooting section of the wiki and solve 80% of the issues with my info alone......

sjb266 · Jan 9, 2019

Haven't really had that issue Anton.. had some slippage on one motor.. took it apart and used isopropyl and file and no problem since..

I took a lot of care to get all the actuators mounted to within a mm or so of each other in regards to height..

There aren't really any calibration tools or such that I have noticed in the software.. i suppose it relies upon initial installation.. maybe recheck all your motor settings one more time..

RowanH · Jan 9, 2019

Regarding feet coming off the floor - I had my front left and rear left motors back to front. It didn't feel quite right and someone else sat in it while I watched it and I noticed it, and saw when one corner went up/down diagonally one of the legs was off the ground. I went and rechecked the wiring and found out my mistake, switched to the correct configuration - the rig obviously felt better, and the legs weren't lifting off the ground.

Mine only gets "air" now when there's a particularly violent crash.

sjb266 · Jan 9, 2019

So i've been driving using the default profiles for a few weeks with some tweaking and experimenting here and there.. Mainly play in AC and iRacing...

I installed the 60hz plugin from discord and loaded up Jochan's RSR profile for iRacing - Dear Lord! It's like it has transformed the whole thing into something else entirely.. I cannot believe how good this profile is... I was running the RSR around Bathurst - and I've done thousands of Laps around Bathurst... and this was the most i've ever enjoyed it..

I think the default SimFeedback profiles are great.. but this profile is just incredible! Where the default profile feel like your in a softly setup car on tyres with big sidewalls.. this profile is like you're sitting in an RSR on race tyres and the bumps travel through you.. it's hard to describe..

But for all of you who do not have iRacing memberships I urge you to get one and try out this system with the new cars that have been released over the last 12 months or so... For me it's in a different league than AC, R3E etc...

That's all..

Steve D · Jan 9, 2019

@anton_Chez

Sounds like you are getting there.

Re, calibration, I just used the jog function to gently wind the shaft back to the bump stop. It hits it and then rebounds a fraction and I was happy with that.

Also, what is your spacing between actuators, front to back? Mine is set at 98cm as seems to be recommended although I wouldn't have thought being a bit more than that would be an issue. Much less and you might have issues with balance!

Finally, I noted your comment re extending the rift sensor cables. Have you thought about attaching a powered hub to the rig. I'd done that, (x2 hubs) and attached a plug extension as well. These support every device attached to the rig so that I can keep cable extension to a minimum and it means none of those cables are potentially put under any strain when the chassis moves. As a result cabling from the rig to my PC is minimal.

Look forward to hearing you've cracked it all.

anton_Chez · Jan 9, 2019

Thanks for the feedback guys. I'll give a little back on what I've found today.

The USB connection has not come unstuck in the couple of hours I've been messing around today. Powered 2.0 hub connected via 2 small extension leads into rear 2.0 port, and Arduino plugged into the hub on its own. No issues. Driving myself, watching AI driver, Start Stop multiple times over, no issues. So it seems that we've solved that, for now.

I have no issues relating to EMI or power as some others have experienced. However I am yet to try VR. My control box is plugged just like anything else is, nothing special. I didn't allocate a dedicated wall socket for it, I wanted to see how everything worked in an ideal situation first. Seems to be fine. Kill switch works as intended, no ill effects with direct drive, no stutter on screen or anything like that. When the Arduino is connected to the servo drivers there is a tiny whine from somewhere but I wont hear it with earbuds, there's no one else around and when the connection breaks from SimFeedback it disappears. Other than that I've noticed nothing out of the ordinary.

Now, the actuators. I've measured each one from the floor and the top of the motor on every single one is 610mm. Give a mm or so but they are exact. I had an issue today where the RR actuator refused to raise. I was tilted halfway through a lap and **** myself that I was going to tip. It probably wasn't that bad but having never experienced this type of motion before it was weird. Got out, ran a jog test just to eliminate any software issues, motor can be felt spinning but no movement. Pulled the motor off and found the coupling attached to the ball screw was spinning. Tightened the hell out of that as much as I could and retried. Seemed to fix it. I think eventually I will take the steps others have of prepping the coupler and shafts but for now they're all mounted and working and are actually easier to work on the way that they are now. This is probably responsible for the lifting of LF as the RR was not operating to its proper travel. So hopefully that solves that as it's the only time I've seen it. Will monitor further by watching if position on the vibration pads changes.

I've just measured the raised position of the motors when you hit Start. FR is slightly taller than the rest, FL slightly below that and the rears are about the same to each other but about 5mm and 7mm short of the front two. Could there be something I've done in the actuator build to cause this? When they retract they all go right to the bottom except for FR, the tallest one. Can I fix this in the servo driver itself? I could just position it slightly different but I'd rather adjust a setting as they are all exact from the floor once retracted properly. I have to lean on the FR to get it to go the extra 4-5mm it needs to retract properly.

I JUST did it again now, but when it raises, there's a slight bump at the front. I measured it again and it's now within 2mm of the rest. Retracted them, and all the shafts are completely retracted, even FR. It's weird. I'm not doing anything different, just hitting Start and Stop but sometimes it's like it auto levels itself and other times, it doesn't. Just want to know how to make it like the second time all the time.

As I said, anton's troubleshooting page for everyone to see!

anton_Chez · Jan 9, 2019

@Steve D got the powered hub powering the control box now so am going to try the same hub for the Rift and see how we go. Got an HDMI repeated as well but this didn't work on its own with USB extension cables and I also think I tried the repeater with the Rift directly plugged to the PC so it still may not work for me. People have had varying degrees of success with extending it and I think I'm in the SOL category. Not to worry, I've made peace with not being able to hang it off the handbrake with the cables staying exactly where they are al the time so as long as it WORKS, I'm not going to complain too much. It has a decent length out of the box anyway so it's not too bad.

Does jogging the motors have a permanent effect on where they start/stop? I mounted everything with every shaft completely jogged back into the actuator. I will have to check the settings again to make sure they are all exactly the same, but as I said in my above post, I get varying results so I'd like to know why and just settle on it being correct all the time.

Actuator spacing is: 600mm left to right and 1120mm front to rear. That's measuring just the space between the metal, obviously add another 200mm to each measurement to get the outside corner to corner. I had no choice at the front, there's heaps going on with the pedal mount on the GT1 but I could move the rear closer together. I don't really want it on a savage tilt and the GT1 is pretty compact as it is, so having them right on the corners I reckon is not too bad. Also if I move the rears up a little they may infringe on my driving as they might be in the way of elbows and such being as large as they are, especially in height. For height mounting I put the brackets at the very bottom of the actuator to minimise the height requirement.

The feeling? AMAZING. First impressions are so good! Default profile, everything stock, 1200rpm and no V3 yet. Can't wait to test more from here. Just need these little things sorted before I dive in properly.

Also, I don't think I've seen your rig before? Seeing as I am mostly responsible for it, it's mighty fine sir! I didn't realise you had the Simwind. Thoughts? I was thinking about it but I don't know if it's worth it.

Insert Coin · Jan 9, 2019

Regarding mounting an Oculus sensor on or off the motion rig: did anyone try Real Head Motion in AC with his motion rig? Does it help when the sensor is not on your rig? (Just a thought.)

kiekoon · Jan 9, 2019

Hello everyone, I'm going to start this project too. I have some questions :
- I live in France and I wonder about the connection to a 20A circuit breaker. Is that enough? If someone from France has already built these actuators ?
- My budget is limited, can you tell me if printing in PLA is better with 30% filling. I would like to have the parts printed by a third party, I will not buy the 3d printer
- If i don't use the grease gun, how grease the ball nut ? I think spray on the ball screw
Thanks a lot for your answer

HugoB · Jan 9, 2019

kiekoon said:
Hello everyone, I'm going to start this project too. I have some questions :
- I live in France and I wonder about the connection to a 20A circuit breaker. Is that enough? If someone from France has already built these actuators ?
- My budget is limited, can you tell me if printing in PLA is better with 30% filling. I would like to have the parts printed by a third party, I will not buy the 3d printer
- If i don't use the grease gun, how grease the ball nut ? I think spray on the ball screw
Thanks a lot for your answer

- 20A is enough. Some people run with 15A circuit breakers.

- With PLA, just ask to use the standard settings for PLA but add the changes mentioned in the GitHub. 20% is enough, but the infill pattern needs to be the correct one (grid) and also the top and bottom layers must be 12. Perimeters need to be 8. And you need a solid later every 20 layers. This is all in the wiki. https://github.com/SimFeedback/SimFeedback-AC-Servo/wiki/3D-Printing

- Greasing the ball nut can be done with any ‘multi purpose grease’ or with this spray:

If you have the time and patience, I recommend to read this whole forum, almost all questions have been answered here multiple times now

HugoB · Jan 9, 2019

@anton_Chez Good to hear you are having some progress! When everything works, it’s the best thing since sliced bread

I know everything that you need to do/unscrew/change/lube/file/re-route/etc is time that you don’t want to spend, because you’d rather be racing!

But still, I’d STRONGLY recommend that you build these actuators right and as accurate and solid as possible, because over time, any imbalance or any play will wreak havoc on their construction. Also it can be very frustrating if your motion is always slightly off or bent, and you will never be sure if your motion is working 100%.

I’m a perfectionist, I couldn’t live with the thought that some of the shaft mounts could be slipping

In your case, I’d just plan one day less racing and spend that day (it will be done in a couple of hours if you’re fast) dismantling the shaft couplers, de-greasing them with isopropyl and sandpaper and file them down. Then screw them on as hard as you can by hand and you will never have a millimeter of slip ever again!

See my post about my best attempt to stop slippage:
https://www.racedepartment.com/thre...-simulator-thread.159524/page-61#post-2881075

Next thing I’d do is identify that slider that doesn’t slide down by itself easily when you stop the SimFeedback, take apart the actuator and sandpaper it down (or faster, dremel it down) until it slides easily. Then apply plenty of PTFE dry spray.

Your rig should easily drop down completely on all four corners when you press stop.

Also, when I mounted my actuators, I mounted them as exactly as I could, they are mounted all within 1 millimeter height difference and less than a degree of angle. Probably this was all too much care and probably ballpark would also work, but I’ve never seen my rig move or any leg going airborne

If you do it right, I can believe this system will last YEARS of daily duty

And if anything wears out it’s an easy swap or re-print

kiekoon · Jan 9, 2019

Thanks for your answer. I read this whole forum but I did not remember everything

I don't see how greasing the ball nut without the grease gun. Is there a hole for greasing ?

HugoB · Jan 9, 2019

kiekoon said:
Thanks for your answer. I read this whole forum but I did not remember everything I don't see how greasing the ball nut without the grease gun. Is there a hole for greasing ?

Haha yea it’s a massive thread by now

You don’t need the grease gun, it does nothing special. You can use your fingers to put the grease on if you don’t mind.. just apply some grease, then turn the ball nut over it and spread the grease around over the screw. The grease gun only helps to put the grease on the screw without getting your hands dirty, but mine got dirty anyway because I had to help spread it out a bit.

kiekoon · Jan 9, 2019

Now it's clear ! I will order the parts

anton_Chez · Jan 9, 2019

Perhaps I misinterpreted the wiki. I didn't grease the ball screw, AT ALL! It says optional and since I didn't have a grease gun handy, I just assembled it without it! I greased the bearing as instructed though.