G-SEAT

The seat bucket surge turned out better than I had hoped. The feeling is fantastic.

So a couple of pics from before.

I needed to convert my push only actuator into push pull.
So I milled some brackets and welded them on to the steel rod.


Worked great!


Printed a cylinder to flip the ball nut on the screw without loosing balls.


Some assembly and this actuator is all set.




I drilled a hole in the steel rod and bolted on this bracket. Now I can screw this down to the wood on the seat bucket.

Got my seat bucket wood mounted to a linear bearing.


Plywood board and seat pad go on top of these 2x4s as marked.


Here is that bracket I made for the steel rod. Kind of silly how small I made it. I used 3.5" long wood screws (predrilled) and it has survived pretty well.


I want this seat to be tried by many so I made the left hinge able to be adjusted. This has come in handy since the gseat has to be fit to each person to get the right feelings.


I can adjust the position of the stepper motors with a pot mounted to the rig. Sadly the little nema 17 motors will skip steps when moving if the body is relaxed in the seat. It will not skip steps when still so if you lean forward during an adjustment it works well.



Since this seat wraps around the body so far it really needs to be dialed to the person driving. This is a pain but I happily go through the work since the outcome is so excellent.

Since this seat has a lot of curvature i don't have good mounting options for the dayton daex32ep-4 exciters. So I jb welded these washers to the chair as they are a perfect fit.

In the video I posted above you can hear the exciters screaming all the game audio full spectrum through the seat. Feels great! I plan on diving deeper into tactile later. For now I just plugged in 4 4ohm exciters wired parallel and series(adds up to 4 ohm) into two HW-576 amps. One for each paddle. 8 exciters in total. Audio mirrored from the vive to the amps.



I really love hearing the different vehicles engine characteristics come through. As you can see I drive with headphones while the seat is screaming because they sound better than the seat with my body against it. The combo is excellent.

Next on the agenda is to add heave and traction loss to the seat bucket. Stay tuned.

this build log is crazy!

I've tried a commercial simulator once with an unknowned but wonderful low bass buttkicker and I felt like seated straight into a living car! Maybe you could try a bigger and more heavy bass shaker?

Good call.
I've got an interesting ace up my sleeve for low bass tactile. Hoping to inspire the community but I'll wait until my teeth are rattling out before I get loud about it. If that idea isn't the best then I will differ to butt kickers for sure.

Very cool build @cfischer!

Did you need to add any motion cancellation on the VR headset to keep from getting nauseated? With the smaller movements on your G-seat compared to a motion sim, I was curious if it would still be necessary.

Thanks for the kind words.
I have messed with motion cancellation on my pegleg frame but don't find it necessary with the gseat.

This does bring me to a false cue with the seat though. As you can see I get moved side to side quite a bit with surge. I am moving in the wrong direction. This is a natural consequence with squeezing strongly on one side. My solution is to tip the torso with a seat mover design in the opposite direction to first cancel out this motion and then maybe add a little in the correct direction.
The same is true of surge. When I am squeezed from both sides during forward acceleration I get slightly pushed forward. Same solution, torso seat mover tipping back during acceleration. I illustrated this with the animation posted earlier. I am excited to report back how this works.

I will say now that these false cues are most noticeable when driving tight cockpits with low roofs. Being so close to the walls of the car you can tell when you move incorrectly. I wouldn't say it was enough to give me motion sickness though. Haven't felt that yet (although a couple of old timers in the shop have, I suspect they would feel sick in vr regardless).

I expect that this gseat will never need any motion cancellation, despite giving a really good feel for the car. This is definitely another reason to be inspired to build a gseat!

I got around these false cues by having the back and base of the seat able to move forward and backwards for surge and left and right for sway, while also having two sets of paddles. The top seat paddles were parasitic, while the bottom were independently driven. In my new sim I am going to try offsetting the position of the paddle hinges so that they let you drop slightly into or back at the center when they close.

Thanks for posting!
I was definitely inspired by your design. My current thinking is that I will want independent control of the torso seat mover part vs the paddles. I think I will want my paddles at really high speeds with lots of fidelity while the torso mover will have more filtering and be smoother. If it turns out the motion I prefer is to have the paddles and torso mover at the same speed/damping then I will remove the two extra motors and use them somewhere else.

Just trying to imagine what you're going to do.
Are you saying you will not use the blue hinge location but something more like the green?

Yes, allowing the centre area to drop back when the paddles close and push out when they open. My gap won't be that wide.

Cool, I look forward to seeing the details and hearing your opinion when you bring it to life - along with your heave situation and ... well, everything!

Wow! This looks great!! Please can you tell us, how it feels? How is the immersion/ feeling compared to a motion sim?

I gave a quick explanation on the previous page before I got the sliding seat bucket.
https://www.xsimulator.net/community/threads/g-seat.15035/#post-204534

Right now I have 4 servo motors setup. Two on the paddles, one sliding the seat bucket and one on the seatbelts. I feel like this setup is light years beyond any moving chasis motion. I've only built a pegleg before this but I'm telling you, I am actually feeling the car. With a lot of excellent resolution. It's great.

@SeatTime has beeing saying it for years and I completely agree. G-Seats are the way.

Your sim is running great and is giving you some serious sustained 'push' (Gs), which is basically impossible on a motion only sim. In my new sim, I am adding back in some motion mainly for situations were noticeable real heave/pitch/roll is prevalent - Eg Aircraft/roller coasters etc. But if your only running cars - easily done very well with just a G seat. Also, as you are not being tossed around - the excellent fast feedback will likely lead to some good lap times.

Ok so as much as I am annoyed spending time showing you something I didn't use, I do think its cool to show failures or things that didn't work out in the name of learning. So hopefully somebody learns something from this.

I didn't like what I build, but I'm glad I tried it. If I didn't I would have always wondered.


Crank arms for the gearbox. I drilled and tapped a bolt right next to the key to clamp it to the shaft.


I made an aluminum spacer to hold the motor mount in place while welding.

Bracket.










Traction Loss:

I thought for sure this would be cool. I had to go back to sim tools for traction loss data as FlyPT Mover doesn't have it. Once I finally did and got it tuned my initial thought was hmm interesting. I put a few hours of driving into it and to describe it quickly, the sensation of my lower body actually moving over was hard to notice. What I did notice was a pressure on the inside butt cheek as the motion came through. Its the same sensation you feel when you lean over slightly in a chair and feel more pressure on one cheek. I just couldn't feel the flex in my hips like I thought I would love. So the effect was kind of lame and subtle.



Heave:

Heave worked pretty well actually. I used low frequency data here only. I also oriented it to sink when I go through a valley and rise when I crest a hill. I actually did like the sink (like I sunk into my seat cushion) but it wasn't enough. I did a lot of thinking and decided that for it to be enough I would have to add a lot of complexity like clamping the bottom of the thigh and pushing down on the helmet etc. I may flirt with this in the distant future. But for now I felt like it was too much complexity for not enough gain.



So I pulled the frame and made a simpler one.

The simpler frame has mounts for two motors for thigh paddles. This was part of the plan all along but I left out the thigh paddles on the last attempt to keep it simpler.

You can see how everything goes together before the wood comes in.


So here are the thigh paddles. Again a prototype. They will be composite like the back paddles someday soon.
I really like the feel of the thigh paddles. They are super strong and bite down into your leg (rather than lift the leg as most seem to do) giving you lots of "resolution" of the force you're feeling.
Adding this really made the sim feel more "full bodied" and really made me wish a g helmet was already setup.
I'm sure a video will be along later.


Let me know what you guys think or want to know!

Progressing well . FI I had something similar for pressing into the shoulders:


were mine had the seat base move your body into adjustable fixed pressure plates for sway. The base seat paddles were only for roll and pressure for heave.

Also had a similar experience with heave, worked OK, but just not good enough for big movements in aircraft etc. which is why I have moved onto adding a full rig ( big ) heave in my new sim.