Something a bit different..

Thanks for sharing, @SeatTime! This is indeed different.

Here is another video, which shows the movement of the seating surface from above and without a driver.

https://www.facebook.com/video.php?v=1785864338180350

Yes, I really liked the concept, as it works similar to my own system that moves the body in relation to the seat and steering wheel.

May even rig something up for a play (just surge and sway), as I have most of the required hardware already fitted to my rig.

I'm also tempted to give it a try. Since I am finally satisfied with my solutions for heave and sway (I recently replaced my backrest paddles with rib cage paddles), the only force that needs improvement is surge. I could imagine to mount the seating surface onto a pair of car seat rails. I will give this a try if I don't manage to improve my current 'surge' approach, which is based on inflatable bladders. (Did not manage to get them completely air-tight yet.)

By the way, the g-seat from Geko Systems (https://www.gekosystems.com/) also seems to have a body-moving part. In this case, it is the pilot's torso that is moved sideways for simulating the sway force. See this post of @dododge, who pointed me to this approach.

Yeah as soon as I realized what this rig was doing I thought of the Geko design. This is certainly a lot fancier since it's 6DOF, and I'm guessing it uses absolute positioning so it doesn't require you to push back against it to get the effect.

I notice that in the video they also have tubes and pumps for an air bladder system, though it's not clear which forces they're using it for.

What's does looks wrong is that the lower part of the body is leading the top, which is never the case in a real force situation.

Yes, indeed! I missed those pumps completely until you mentioned them.
The nice thing about this bladder approach is that you can put the bladders wherever you want them, and it is easy to adjust their position for optimizing the effects.
The drawbacks - at least to my experience - are:

• It is hard to get the system completely air-tight, so that you need to re-fill air from time to time. (I held my pneumatic system into the bathtub for finding leaks. However, when the tubes are moving, leaks may re-occur.)
• The force applied to the body is somehow softer and not as abrupt as with paddles.
  
• Releasing the air - at least in my case - is only done by my upper body pressing against the bladders. It would be better for the effect if the air is sucked out. I thought of connecting the motor with a pneumatic cylinder, but the volume of the cylinders I found is too small for the bladders.

Yes, correct. But maybe the inflatable bladders are used for applying pressure to the upper body and in this way complementing the rig. However, the bladder system is for sure considerably slower than the moving seating surface.

The Frex AirG-Force system incorporates hand bulbs and release valves for adjusting the pressure. You can see them hanging off the back of the rig in the video. It looks like they use a solid reservoir and actuator that can suck the air back from the bags, but it's not certain.

Shit.....
Iam now totally addicted to the whole motion thing and what you guys all doing.
Got my 2Dof system for about 2 weeks and already looking into new features.
That Frex AirG system looks interesting