Showroom 2 Dof Seatmover with Cytron MD30C

Hello there,

I'm completely new to this forum as a member, but I've been watching it for a long time, dreaming of my own motionsim.
Now, finally, the time has come and I'm starting to build one!

I've designed a custom rig wich will also carry 4 bassshakers and a windsim. Since it'll be my second selfmade rig, I know what I have to keep an eye on concidering dimensions, so that part works out.

What's kind of new to me is the softwarepart, I have some questions regarding how it behaves under specific conditions. But first, I'm going to show what my rig is all about:



This is a rendering, showing the new 8020 profile rig with some steelparts I designed.
I'm using a Sunrise 80ZYT165 Motor wich together with the wormdrive will create around 63 Nm.
I want to drive them with two Cytron MD30C motor drivers.
I have bought two 500W power supplys, one for each motordriver, to keep things seperated.
Since I don't want to use a battery for regenerative breaking, I've bought two shunt regulators, wich the team of cytron told me to do.
Instead of potentiometers, wich will degrade over time, I'm using hall sensors, wich should work the same way from the arduino point of view.

I'm still waiting for parts, so except the baseframe nothing is built yet, but I have a question before even starting, because that could make things easier.

I've read a lot about SMC3 and also found out already, that I need a modified version for the MD30C, because otherwise the motor would behave different in one direction. In that same thread somebody wrote, it is mandatory to start Simtools first, and then fire up the system. Also, you should turn the system off before closing Simtools, because otherwise the motors would ignore the hall sensors input and just spin, wich would destroy my rig, as the levers cannot do a full rotation.
But what if my pc crashes? What if the software crashes?
From a logica point of view, wouldn't the arduino just send a 0 if it does not get any input from Simtools? Wouldn't the system just stop, if the pc is turned off? Because if not, if the system will really just spin endlessly instead of stopping, when no signal is detected, then this would be the wrong solution for me...
Can anybody clarify that maybe? Also, what if the arduino breaks or a cable of the potentiometer will come loose? Will SMC3 stop the motors if one of the pots or the pc won't give an accepted signal?

I think that's it for now, I'll post some more details when starting to build. If I've forgot anything, please tell me, I'll do my best to provide every information needed!
Thank you!

I like the specs and price on that motor. I’m also planning to use the MD30C but you’re ahead of me.

I've progressed a bit after my last post.
The base from aluminium profiles is nearly done, just waiting for the sheet metal parts wich a friend of mine does for me:

Excuse the not so cleaned up room, I just moved here and there's way too much stuff for a small apartement...

I've printed some gimmics that will help me keep the rig clean and do some cablemanagement:

Cables for my motion sim are mostly done. The motors, the e-stop and the sensors are ready to go, I've also printed a hull for the sensor cable, so it does not break too easy:



I've designed a case for the gearing, wich will keep lube inside and dust outside.
The gearing increases one rotation of the motor to three rotations of the sensor. I'm only using around 60-80 degrees of the motor, with the gearing I can make use of the sensors high resolution. The case and the gearing looks like this:

It works perfectly from the first tests, I have to verify that later though.
I've tested the sensor with an arduino and the SMC3 desktop app, that part works like it should.

I already have two T-Amp S150 amps and 4 Reckhorn Bs200i bassshakers laying around. The rendering in post one is outdated, mounting brackets for the shakers have been added to the seatbase and the pedals.

The next few days I'll build a case for all the electronics, so I can start to wire the controlbox.
This will include:

- 2x 500W 24V power supplys
- 2x Cytron MD30c motordrivers
- 2x Shunt regulator for those drivers (polulu 26V)
- 1x Arduino uno R3 with a sensor shield for easy and clean wiring
- 2x 24V to 12V Stepdown, one for the arduino, one for the fans
- 2x 92mm Noctua fans for cooling the motordrivers
- 1x 230V Relais for the e-stop and power switch

The sensors will be connected to the box via GX12 3 pin connectors.
For the motors I'm using XT60 plugs known from fpv-racing.
I've purchased a usb-B extension cable for the arduino, wich will be screwed to the box.
The e-stop will be connected with a powercon plug wich is known in pa technology. It's impossible to touch both pins, that's why I chose this, for safety.

The box will be cnc milled from dibond wich is an aluminium composite material.

I'll try to do some wiring diagrams to upload here soon, I personally don't use any for myself.

I hope the rubber feet will work as intended, keep the ffb and vibrations away from my neighbours but not from me...

I'm still waiting for the sheet metal parts, that could take a while. I cannot wait to finally drive this beast and try motion in ACC!

very skillful rendering!
what CAD software are you using?

could you share a link for Sunrise 80ZYT165 Motor spec and price?

Keep going man!

Thank you!
I'm using Autodesk Inventor for modelling and drawing and Keyshot for my renderings. Works great!

I got that motor from a local reseller, over here in germany. But this is the link to this motor, where you can order it directly from the factory.

It's rated at about 440W, outputs 50RPM max, the technical drawings differ between 59 and 63 Nm, I'm not sure wich one is correct but both numbers should be more than enough (I hope).

https://m.made-in-china.com/product...ushed-DC-Gear-Motor-846702315.html#ampViewAll

A few days have passed and it's time for the next update!
The control box is now finished and works as intended.
While building I noticed a few things I would change, that is:
1. Space for the E-Stop Relais. This one takes more place as expected, due to the thick cables and cable shoes.
2. routing the USB cable. Having USB next to 230V can cause issues with signals due to induction. I would place the usb to the other side of the case, but routing it over the power supplies works just fine, so no need to redo the case.
3. Plugs. I would use different plugs for the left and right motor. If just I'm using this it's fine because I know wich motor goes to wich port, but it can be connected the wrong way around, wich would be a desaster because one motor direction ist flipped, wich would cause the other motor to spin endless when connected to the wrong port. (powering the motor only leads to the feedback going away from the setpoint with the wrong port)
4. Leave place for connectorrails (don't know the correct word) so I can split a single cable to two, with the cable shoes. Now I have soldered those cables instead of using shoes, wich works, but does not look great.

But enough of that, this is how it looks:

The Outside:




The inside:



I've tested the motors already, one has a lot of play (deadzone needs to be 1), the other one has basically zero play.
They're pretty silent, the power supplies are louder as expected though, but still not as loud as my CSW V2.

I'm still waiting for the metal parts, no updats on that side, except they have been cutted already and will be bend the next days. Only welding and painting will be left then, so hopefully I'll be able to finish this thing next weekend.

There have been some complications with manufacturing of the sheet metal parts, but they'll hopefully be done next week.

In the meantime, here's a video of one motor running a sine wave:



It's very silent, I cannot wait to see, feel (and hear) it in action.

I'm currently thinking about adding dampeners, because many people told me that will smooth out the experience. Has anybody here any tips on that?

Sweet Rig! Post some videos in action if you get a chance! DMAX

So, I was able to finally finish the rig!
Here are some pictures of the mess: (The room is way too small to build something)






And here's the finished rig right now:



After the first test runs I found out that I've miscalculated the center of gravity, so my seats rear is a bit heavy. That, and the fact that my 500W power supplys seem to shut down when the 440W motors request full power, keeps the system from pushing me forward when breaking hard.

It took some time to adjust the cog and I'll probably do a second toppart for the platform with the improvements. In addition to that the levers are waaay too long,I'm using around 15% of the full possible movement.

I'll replace the lever with a shorter one, that way I can fight the breaking problem even more and I'll have more precise movements and less play in the system.

But already now I have to say: What a blast! Dirt Rally 2 is the most fun ever with this system. The bassshakers really add to that impression, it feels sooo nice to jump, enjoy the calm seconds to then have a hard landing and continue on rough roads.
The only problem right now is, that although I have anti vibration machine feet under my rig, the vibrations of the bassshakers clearly reach apartements under mine. I don't know how to handle that, if somebody has a great solution, please tell me!

Anyways, here's some driving footage, it was one of the first runs:


Edit: Yes, it is comfortable, I'm 2,04m tall. I've designed the rig to fit tall people, there's much room to go but this is what I'm used to from real driving, everything else feels weird
Edit end

Next up is a better wind system (the hoses take a lot of air movement out), a new shifter knob (wich I already have) together with a short shift shaft I've designed and a new buttonbox (for wich I still have to find a place, because the handbrake is where it normally sits)

the buttonbox will look like this (rendering):


Someday I'll also change the seat (sparco grid-q is my fav), the pedals (heusinkveld sprint) and the wheelbase (simucube sport). Dreaming...

Man that looks AWESOME! Good Job ! That is a quality build and you should be proud dude! DMAX

I use a 850CCAmps battery for my power. So no friggin way it's going to shut down. None of these motors posted on this channel could make it stop. Except I have a 50 amp breaker, just in case. Check out my rig on youtube or here. DMax Motion Simulator or Halloween2go on this website here.

Well, there goes the shunt regulator! Thank you, Cytron, for wrong information... Luckily I got away without any other damages, at least I hope that the power supply is intact... That amount of smoke was scary!

Does anybody know any good alternatives for the Polulu shunt regulator or should I just install 2 or 3 in parallel and with better cooling?

The new solution for dealing with regenerative breaking:


Each of the two packages contains:
1x 3D-Print-Part
2x Shunt Regulator
2x 470uF 35V Low ESR Capacitor
2x Raspberry Pi cooling block
2x RAM cooling block

That looks like this:


They are both placed directly under the case fans.
So this time I've doubled the allowed power, I've added more heatmass, I've relocated the unit inside the air flow.

Until now (2h of racing) the unit lasts.

I noticed the motors stay absolutely cool with the new 30mm levers that a friend made for me:


Now the thing feels incredibly detailed and powerful. Just what I wanted!

Hi, just want to say what good build this is, I'm looking to do something similar but maybe not as high quality
I'm wondering if you ever had any issue with the cytron motor drivers like how you described in your first post? Where you mention about starting simtools first then powering on the rig, and reverse when shutting it down.
Is this only when initially setting up the rig or every time you want to use it?

Hi,
hank you for the kind words! My plan was, to build it as well as some kit you'd buy, a clean solution, so I'm glad that the effort was well invested!

After I updated my regenerative breaking solution to the more powerful one I never had any problems again. The power on "issue" never was a problem, I've read about that once, but for me that never was the case. If I start the rig without the software, nothing happens! The motors will stay in the position they where left in. So nothing to worry about!

Thank you for such a fast reply on an old post
That was the only concern I had going forward with my project so I'm glad to hear it was not an issue, how have the controllers been holding up?

No problem! It's an ongoing project and I still want to update this post with new changes, but cannot find the time.
The Controllers have been holding up great, no issues at all! They have plenty of power, so they stay cold most of the time. The only "issue" I can think of is the gearlash in the wormgear-drive fitted to the motors. I had the Idea to use actuators like the ones in the SFX100 System, but smaller, under the seat, with rockers to transfer the motion. I love the compact formfactor and want to keep the seat adjustable, that's why I need a small package. Maybe someday...

It's been a long time since the creation of this Post, and a lot of things changed! Some updates:

The Buttonbox was finally finished:



I changed the pedalset to Heusinkveldt Sprints and made a new base to fit them:



I could not be happier with the pedals, worth the upgrade, a whole new world compared to the Fanatec CSP V2s.

Since I'm using triplescreens, I wanted to implement a bezelfree kit. But there where some issues: The original one is expensive, not available and also too short for 32". That's why I made my own from a layer you can find inside an old LCD screen:




Since it's not really made for this usecase it doesn't work exactly as well as the original bezelfree kit, it's a little darker, but that's about it. Finally the black bezels are hidden, also well worth the work. Sidenote: Switching to a bucket seat helped a lot with immersion, since now sidewardsmovements are transmitted as never before, since the seat really holds me tight.


Incidents happen: It turns out, that the gearing-case of those wormdrive motors is not the strongest, as one of them broke on a heavy day of racing:



Quick fix: I designed a simple part, wich a friend of mine milled for me. I guess, that will survive longer than the whole rig!



So, for all of you planning to build such a seatmover, make sure to not only use the bottom mount, but also the top or sidemounts.


Like a smart person once said: A piece of art is never finished. Next up will be a new wheelbase with custom wheels, a new handbrake and some changes to the sheetmetal parts of the rig... I'll keep this updated.

Until then:
Happy simracing!