John Pritchett · Physics Programmer

Okay. Well, one of the real challenges for a system like this is I don't want to implement a very specific hover behavior. I want it to be a very generalized system and then turn that over to the designers and give them a lot of flexibility for them to decide this is a bike or this is a tank or whatever, and get a lot of variation out of that. So there are some specific approaches that I've taken for how you can implement or tune hover for all these different vehicles.

So for the Dragonfly and the Nox, really not a lot of variation there. I kind of see the Dragonfly as being more of an off-roader and the Nox being more like a road bike, a street bike. So you tend to want the Nox to hover fairly low and require fairly flat terrain, not a lot of variation, without it starting to bottom out and things like that. Unfortunately, right now there are a few issues with the Nox. It's not even behaving as well as I would expect it to. Even on straight flat ground, it's dragging. But the Dragonfly, you'd want to be able to get out on a little bit more rough terrain and feel the bumps and have a little bit more control over rough terrain.

And so really to achieve that, I have a system where the hover vehicle control system is basically determining, based on the terrain that you're over and also the terrain that it sees coming, what it wants its elevation to be. And so it's constantly saying, okay, I need to be 10 meters off the ground right now, or five meters off the ground or whatever. If you're on a nice flat cruise, then it can be right down there, half a meter off the ground. So it sets a goal elevation. And then the physics of the system, essentially a spring simulation, is going to determine the rise and fall. Well, not actually the fall; the fall is generally going to come from gravity, but pushing it up to achieve whatever elevation the control system is looking for. So I think what we're seeing as the main issue is that the control system isn't getting enough data really to be able to make good decisions about its elevation, as opposed to the system not being able to achieve the elevation that's desired.

So anyway, getting back to your question, you're asking how I've implemented it in order to achieve the vision that we had for hover vehicles?

Jared Huckaby · Host, Community

I was just asking what your vision was.

John Pritchett · Physics Programmer

Yeah, well, so that's basically it. I just wanted it to essentially be as close to a physically realistic, acceleration-driven hover, being very, very careful that the Gravlev itself is only ever really pushing you up. So then if you go up, the gravity is going to pull you back down. So you feel like you're kind of catching air. It feels like you're jumping, as opposed to a system that's managing your full elevation up and down. And then of course Gravlev is really frictionless when it comes to lateral. So when you're turning and things, that's when thrusters from the vehicle are going to come into play. And that's, I think, something different that we do than you see with a lot of hover bikes in games: it's a hybrid atmosphere/space vehicle. So it has full thruster control when it needs it. We go into hover mode really, I think, more as a matter of efficiency, because then you're not having to burn thrusters to stay aloft and you can save on fuel and all that. But you're still using those thrusters for a lot of your maneuvering.