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

RaceNut · Oct 14, 2018

@HoiHman
I wish I had a rig like yours so I could join in and compare notes.

That's one advantage to the D-box system (certainly not the price of admission

), it is refined in how it works and in how easy it is to use. Of course, the development of the system has existed for some time and the usage in Cinema makes the need for such refinement quite significant.

I suspect the D-box doesn't suffer from "crawl" because the synchronization between actuators is so tight and controlled; the only actions that may cause the rig to move are likely to be the higher frequency vibrations but, the feet do a good job of keeping them in check. It's worth mentioning that there is a good amount of play between the actuator friction-bases and the feet that rest on the floor so the rig can move around slightly (maybe 8-10mm of free movement) within the cups.

I wonder how much the consistency in vertical-alignment of the actuators factors-in regarding tendencies to creep. Perhaps studying patterns of rig-movement might reveal some possible cause and effect and the role inertia, torque, velocity, etc., may play.

Mascot · Oct 14, 2018

Just load the rig down with sandbags!

C64 · Oct 14, 2018

@HoiMan

I’ve been thinking about the problem of your rig walking across the floor. If you can prevent/lower the sideways forces on the feet then you should be able to limit its movement. One thing I thought might help is to put a rolling spherical ball on the end of each leg, on the floor have plate with a recess in it for each leg that will allow the ball some freedom.

This is what I was thinking of... use inverted

https://www.ebay.co.uk/itm/5PCS-CY-...497698?hash=item25fe230462:g:SZwAAOSwz5FanSXn

RaceNut · Oct 14, 2018

C64 said:
@HoiMan

I’ve been thinking about the problem of your rig walking across the floor. If you can prevent/lower the sideways forces on the feet then you should be able to limit its movement. One thing I thought might help is to put a rolling spherical ball on the end of each leg, on the floor have plate with a recess in it for each leg that will allow the ball some freedom.

This is what I was thinking of... use inverted

https://www.ebay.co.uk/itm/5PCS-CY-...497698?hash=item25fe230462:g:SZwAAOSwz5FanSXn

What you describe is essentially, what the D-box design does; the actuator shaft has a nylon-like pivot. It allows the rig some room to roam but, ultimately confines movement to a limited area.

C64 · Oct 14, 2018

Hmmm... so may work. I’ve ordered some of the bearings and will try in a couple of weeks when all the kit arrives.

Michal Burisin · Oct 14, 2018

I saw similar solution here:

Ringorian · Oct 14, 2018

@HoiHman Just ask the question in discord so Michael also Sees it
... Afaik it stops at 5/20 percent ...

Ringorian · Oct 14, 2018

https://github.com/SimFeedback/SimFeedback-AC-Servo/wiki/Software
At The bottom is a description of the values Incl Picture

Little explanation for the Others. Just that you understand why it was jumping around , Not to be rude to Henk or have a Joke on him. Cheers Henk

This should Clear Things Up and Stop Some maybe wrong Impressions ..
If you give Pitch 5 cm travel in complete plus surge 2.5 cm and Go offtrack Into a Wall .. the simulator Pitches because both effects use pitch ..
And that in this ~7.5 cm Up And down with Lots of Speed .. until your car Stands still. Thats why it walks

Check my Videos or Florentins, we use hard and fast settings but its Not jumping
Around since we dont use more way we need to have a good Ride

To get nearly the min max Data ...
At The Moment you have to live Check while driving with Realtime data active or Like me Using my mobile
And record Video while driving. Afterwards i Check the Video

sebna · Oct 14, 2018

Is there a plan to create some kind of repository of profiles which could be used by new comers and in general for sharing of the profiles?

Ringorian · Oct 14, 2018

We want to do this over the discord Channel .. centralized .. its hard to Monitor all the Forums .. its the easiest way .. and the Users can Exchange them there. Thats our Plan or wish

cprelot · Oct 15, 2018

HoiHman said:
30mm diameter
minimal inside diameter 18mm, no thread
min 270mm long (if you make them longer, the actuator is longer and the rig stands higher)

The one in shopping list has a 6mm thick wall, but 3-4 mm will be good enough as long as it's 30mm thick and hollow.

Ok cool!
However I can only find hallow shaft 30mm outside and 17mm inside
do you think it's fine since the Ball screws is 16mm? or must be 18mm minimum?

sjb266 · Oct 15, 2018

cprelot said:
Ok cool!
However I can only find hallow shaft 30mm outside and 17mm inside
do you think it's fine since the Ball screws is 16mm? or must be 18mm minimum?

All the Chinese hollow shaft have 20mm bore..

Let me know if you want a contact..

Moxley6969 · Oct 15, 2018

sjb266 said:
All the Chinese hollow shaft have 20mm bore..

Let me know if you want a contact..

hrm, i didn't find a Chinese shaft, tho dont recall lookin too hard before settling on the musami,

Post up the link eh.

anton_Chez · Oct 15, 2018

@Ringorian Is there any way any of us following this will be invited to join the Discord? It would be awesome to see what others are doing that aren't a part of this discussion.

cprelot · Oct 15, 2018

sjb266 said:
All the Chinese hollow shaft have 20mm bore..

Let me know if you want a contact..

Yes you are correct I fund a nice guy on Aliexpress Kevin Ho from this store (RDB Bearing and Mechanicals part)
he told me he can have inner size 17/20/24mm
I tough 17mmm was closer to 16mm from the ball screws, so you think I should go for 20mm bore then?
he told me also the inner size are more rough and not precise like the smooth outsize 30mm

can you give me your contact where you source from?

thanks
I

cprelot · Oct 15, 2018

Moxley6969 said:
hrm, i didn't find a Chinese shaft, tho dont recall lookin too hard before settling on the musami,

Post up the link eh.

Yeah sometime you need to dig deeper and don't hesitate to ask them even if you think they don't have it

but like sjb266 said we need to fund out when we receive the order to test quality and then to spread those links
but here
https://www.aliexpress.com/store/334759?spm=2114.12010108.0.0.6d0658fbDikQPn

sjb266 · Oct 15, 2018

Is the signal input for the servo driver 24v or 5v?

metalnwood · Oct 15, 2018

I bought these and they arrived a few days ago.

https://www.aliexpress.com/item/30m...linear-shaft-rod-for-CNC-DIY/32685139057.html

No problems with them, the only thing is that they are not cut completely square. They are 20mm inside bore. I just put it in the lathe and the internal bore is out of center by about 0.1mm so no issue there.

Still, if I had the option I would go for 20 not 17mm as 17mm only gives you half a mm clearance and if it is not drilled out perfectly it may rub, other things come in to play like a screw that is not completely straight as well as the whip that could happen from an unsupported end at high speed. None should be an issue that will impact performance but the 20mm bore should ensure no internal rubbing.

HoiHman · Oct 15, 2018

Ringorian said:
https://github.com/SimFeedback/SimFeedback-AC-Servo/wiki/Software
At The bottom is a description of the values Incl Picture

Little explanation for the Others. Just that you understand why it was jumping around , Not to be rude to Henk or have a Joke on him. Cheers Henk This should Clear Things Up and Stop Some maybe wrong Impressions ..
If you give Pitch 5 cm travel in complete plus surge 2.5 cm and Go offtrack Into a Wall .. the simulator Pitches because both effects use pitch ..
And that in this ~7.5 cm Up And down with Lots of Speed .. until your car Stands still. Thats why it walks
Check my Videos or Florentins, we use hard and fast settings but its Not jumping
Around since we dont use more way we need to have a good Ride

To get nearly the min max Data ...
At The Moment you have to live Check while driving with Realtime data active or Like me Using my mobile
And record Video while driving. Afterwards i Check the Video

Thanks for the tip of the realtime data check while driving Jochem.

I kinda feel like i'm the 4th beta tester. The unknown factor

In all honestly guys, i probably went a bit too far. This is partly caused by me missing my GS-4 and the larger surge travel of the NLMv3. When tuning i was trying to over compensate for missing those 2 factors

In my defence: Tuning a motion rig while in VR is difficult enough as it is. When you start of in the expert tuning, you should have some visual clues to what the rig is actually doing. So for now i will stick to the basic tuning and use the basic profiles.

I drove a couple of races this morning and the rig didn't move a mm.

The new plates seem to be working great, but tuning down the motion was needed to.

This week i'm gonna concentrate on finishing up some customer wheels and then start moving around stuff in the office. For the tuning fase i will find a way to race on one of my 46" TV screens while using my 40" monitor to tune and watch the live data while driving. Visual clues to what the rig it doing will also help spotting when you go too far. I hope by that time the GS-4 can be fixed to, so i can combine the tuning of both systems.