DYI G-Seat

[Michal Burisin]

So I finally got to the point, where I can start working on the G-Seat.

Here is my latest progress with the rig in general.

What's important for G-Seat part of the project is tactile installation on the seat, which consists of 3 BK Concert + 1 TST 239, so it's pretty powerful tactile, so I must make sure nothing rattles, this will be challenge as there will be many moving parts.

I'm using Kirkey Aluminium Seat, link is here.

I have 17'' version and it fits me like a glove I'm 168 cm, around 66 kg, quite thin with broader shoulders and it's so so, especially with the G-Seat paddles. I'm striving to take around 2,5 cm of space from the internal volume with paddles.

Here is the parts overview:

A) Bottom paddles - with big space between them - I don't want to simulate heave, maybe just a little, but it's intended mainly as pressure from the sides.

B) Main back paddles - narrower gap between to allow for some pressure during acceleration.

C) Additional back paddles for sides - just for thin guys, I made them removable to allow someone with bigger butt to fit in there

I spent day and half measuring etc., here are some images of progress:

Now when I printed it on A3:

And with additional paddle from the side:

I'm really happy it worked so well! I just have to correct 2 lines where the plate would be bent and that's it! I don't need to tweak the shape any more, it fits perfectly!

I will be probably using 4x ASME-04A servos for 4 paddles and 2 for seat belt tensioner.

The servos for bottom paddles will be located on red profiles like pictured below, on these profiles will be also servos for seatbelt fastener.

Servos for back paddles will be mounted to the seat.

The servos axles are goint to be extended by this connection - 8 mm to 12 mm, for 12 mm shafts I use aluminium hollow shaft with 2 mm thick wall.

The shaft will be like 0,5 m long, so at the end, it will be fixed in ball bearing with housing connected to the seat to prevent shaft bending.

Along the way there are going to be 2 points on each shaft with fixed clamp.

 

[Hees]

Hi Michael,,,,
Thanks for the informative feedback.
Good to hear that its working, i did notget the last point yousaid though, why high forces are making you less precise?!
Also regarding the build how much is the weight total?
Also are planning to commercialize it or same as the sfx100.
Lastly the approximate time to make it all together lets say if you dedicate 10h a week

 

[Michal Burisin]

Hi Michael,,,,
Thanks for the informative feedback.
Good to hear that its working, i did notget the last point yousaid though, why high forces are making you less precise?!
Also regarding the build how much is the weight total?
Also are planning to commercialize it or same as the sfx100.
Lastly the approximate time to make it all together lets say if you dedicate 10h a week

When you are for example jumping kerbs in chicanes, the paddles push to your sides very quickly and very strongly and that moves also with your hands and steering. You cannot be as precise as on static rig with all the forces acting on you. It's more realistic, but realistic is slower than SimRacing on static rig, where you have much less variables to deal with (G-Forces, bumps etc.). On static rig, you don't get get so much information but you can replace it with muscle memory.

On weekend I'll take the G-Seat down, I'll try to put it on scales to tell you weight, but I think it's a lot, but I got like 20 kg worth of tactile on top of it , without it it still might be 30 - 50 kg.

This design is not ready for publishing it as DYI ready project, it involves too much custom work. On SFX you have just printing and everything else is made from of the shelve parts, so you just put it together over weekend .

Here you need to have lot of custom plates cut / bent. Than you need to cut holes to the seat. Then drilling to the seat and made plates to fit everything together. It's a lot of measuring, drilling, making threads etc.

I cannot really tell how much time it would take. If you would choose the same seat as I have, you would have it much easier because you wouldn't have to do that much customisation.

It also depends on how good / fast are you with tools and if you have some place where to work on it. I don't have garage so I made it all in home conditions which took me much longer than someone with garage full of tools, vice, stand-drill etc.

If I had to do it again, I think I might manage it in about 100 - 150 hours if I did it same way as I did it first time, but that's just guess, it might be faster but really I cannot say.

If you would choose the same seat, I can outline the steps you need to do. If you would have other seat, you would have to do quite a lot customisation.

I think someone will come with simpler design, but it might take a while but I think eventually some project similar to SFX for G-Seat will appear.

Unfortunately, if I were to simplify this design, I would have to sell this prototype, order everything again and start over, which I'm not prepared to do at the moment .

 

[sberns]

Michal, that is truly some magnificent work. I currently have a DIY Gseat back-panel insert only, on top of an SFX/SimX/belt tensioner system, but my Gseat is still based on RC servos which I’m soon changing to AC servos. I was hoping for a bit of guidance - Can you please advise what is the max back panel travel (from flat against the seat to fully extended) - i was thinking to plan mine for around 8-10cm but maybe that’s too much?

 

[Michal Burisin]

Michal, that is truly some magnificent work. I currently have a DIY Gseat back-panel insert only, on top of an SFX/SimX/belt tensioner system, but my Gseat is still based on RC servos which I’m soon changing to AC servos. I was hoping for a bit of guidance - Can you please advise what is the max back panel travel (from flat against the seat to fully extended) - i was thinking to plan mine for around 8-10cm but maybe that’s too much?

Hi, I have it currently disassembled for shaft change, once I'll have it up, I'll let you know how much travel I have / use.

But I think this one number won't tell you much, it all depends on paddle geometry, pivot point and shape of your body.

I think I'm using like 7 cm of forward push travel at the arms attaching to the paddles. My limiting factor is shoulder width. I'll update you with actual number, I hope on wednesday.

My advice would be to go for more travel and not use it fully than trying to aim for maximum travel you are likely to use, because you'll likely find how much exactly you need after some time of usage and it might be very hard to change it later.

 

[sberns]

Sounds like good advice!

 

[RacingMat]

I've just read the whole post! what a breathtaking project, congrats!

Sorry to hear some setbacks... It's inevitable while R&D. I did know this for 2 DOF or direct drive wheel building back in 2013.

Have you solved your backlash problem? It's a big concern because even if the paddle is always pushed, backlash means loss of reactivity and details.

 

[Michal Burisin]

I've just read the whole post! what a breathtaking project, congrats!

Sorry to hear some setbacks... It's inevitable while R&D. I did know this for 2 DOF or direct drive wheel building back in 2013.

Have you solved your backlash problem? It's a big concern because even if the paddle is always pushed, backlash means loss of reactivity and details.

Hey, I have been little busy lately, so no time for racing.

Yeah, there were a lot of design changes, even when I was thinking it's basically done, some other issue came around, hopefully now it looks good

Not sure about durability. I think I have around 100 hours of runtime, so far without problem.

Regarding backlash, it's much smaller when I changed to AC servo motors with different, higher quality gearbox, which has much smaller backlash. It's still there, but I don't think it's impacting performance / quality of the feedback in any significant way as your bodyweight is leaning into the paddles all the time. I started using heave with very fast movements and it is able to deliver these small details very well. Anyway you feel best the bigger movements, as the smallest movements on bottom paddles are dampened somewhat by padding anyway.

 

[Eric Bergeron]

I've just read the whole post too ! what a masterpeace !, congrats!
could you give me the model no. of the servo , the gearbox , and the link if you can ?
and ..do you use the servo in torque mode ?
thanks