Source: http://www.engadget.com/2015/03/05/roto-...

Simply put, it's a motorized chair platform with a footplate controller you twist to control the direction and speed of the spinning seat. Describing it in so few words doesn't really do the Roto justice, however, as it's much more than an overcomplicated alternative to a mouse or joystick. Sure, it essentially performs the same function, but there's something about moving in time with your virtual avatar that brings a whole new dimension of realism to the VR world.

One of the primary aims of Roto is to give VR users a greater sense of freedom when exploring their virtual surroundings. With a VR headset, you're always focused on what's directly in front of you. Yes, you can turn your head in every direction to see what's beyond your peripheral vision, but we're not owls, and the human neck is only comfortable when your eyeline is centered, or thereabouts. This is true in real life, too, where the natural reaction is to turn your body to catch up with your head when it reaches more severe angles. This is essentially impossible in the VR world if you're seated in a fixed position, so instead of turning your body, you shift your point of view using a controller.

It's an important distinction, or at least it feels significant the first time you twist the footplate and the chair spins in the direction you've specified. You aren't forcing an avatar to give you a different perspective; you're physically changing the perspective in a natural way -- the way you would in real life. When using a controller, there's an inherent disconnect between where you are looking and where you are facing. Your neck is doing one and a computer is doing the other, but when both inputs are essentially physical ones, there's a much greater sense of presence. You're there, moving and looking around, not staring through the eyes of an avatar you've possessed.