[TrevorJ]

The concern I have is that failures in the control software or mechanical failure would have grave consequences. Maybe that's a solved problem and the cable capstans have mechanical arrestors that kick in, etc but the setup looks inherently unstable unless under active computer control (due largely to the crossed cable attach points).

This is quite a bit different than a more typical hydraulic setup where an unpowered/uncommanded state simply leads to the platform settling in a stable configuration.

Having said that: I still want one. :D

[irl_zebra]

Around 25 seconds into the video you can see how thick the cable is. I would guess probably an inch thick. With regular wire rope, the breaking strength of that diameter would be in the neighborhood of 80,000lbs[1] with the safe load strength closer to 16,000lbs. I'm guessing with regular maintenance and checking, it would be exceedingly rare to have a mechanical failure.

Additionally, the occupant is harnessed into the chair, bolted into what is essentially a spherical roll cage. Even with failure, I'm guessing there would be a crash but no serious injuries.

[1] - http://www.engineeringtoolbox.com/wire-rope-strength-d_1518....

[TrevorJ]

It's more about how the cable is managed in terms of slack, keeping the cage from flipping over, etc. I agree with you, the cable itself is an unlikely point of failure.

[jonknee]

You could make the floor foam blocks or a trampoline, but in concept it's very similar to the Skycam used for NFL games and they are very reliable. I've never heard of one coming down (and they have a lot more travel).

https://en.wikipedia.org/wiki/Skycam

[laxatives]

There's certainly been instances of cameras coming down and having near misses with players and referees. Those cams weigh a lot and are moving at high speed as well.

edit: quick search returns https://www.youtube.com/watch?v=GPPJ6rg_TTA

[jakeogh]

I'm surprised they have the computers right next to it... and people standing there. I wonder how they mitigate the possibility of unintentional (error driven) movement?

[jbattle]

Massive wires each under 1.4 tons of tension would make for quite a show if one did break