Robotic swimming in curved space via geometric phase
1–10 of 17 posts
Re: Robotic swimming in curved space via geometric phase
#2Moonwalking on a curved surface eh?
Re: Robotic swimming in curved space via geometric phase
#3This is about a robot that moves around in a curved space by merely changing its shape. Very cool.
Re: Robotic swimming in curved space via geometric phase
#4Could this principle be used to make a reactionless drive for spacecraft? I would assume it would only be effective in an absurdly deep gravity well, like right next to a star, so it's probably impractical; I'm just curious.
Re: Robotic swimming in curved space via geometric phase
#5Could this principle be used to make a reactionless drive for spacecraft? I would assume it would only be effective in an absurdly deep gravity well, like right next to a star, so it's probably impractical; I'm just curious.
Sort of, but not really. This is like reorienting yourself in midair by waving your arms in that it doesn't change your velocity, just your position. So while something like an ion engine can get away with absurdly low accelerations because they build up to large values over time, this gives you an extremely low velocity with no way to increase it. And in space with a high enough degree of curvature for this to work, you need to be moving at a very high speed in the first place to not immediately fall into the source of the curvature.
Re: Robotic swimming in curved space via geometric phase
#6On Youtube https://www.youtube.com/watch?v=BZF1nelgPNs
Re: Robotic swimming in curved space via geometric phase
#7Could someone explain who their robot isn't violating conservation of angular momentum? That seems key to understanding it.
Re: Robotic swimming in curved space via geometric phase
#8Does this also work for curved space time? Or is that type of curvature not going to help because it's relativistic? Or is the shape wrong? They mention that it doesn't work for cylinders.
Re: Robotic swimming in curved space via geometric phase
#9Could someone explain who their robot isn't violating conservation of angular momentum? That seems key to understanding it.
IANAP, but I think conservation laws are always equivalent to some symmetry (space translation, time translation, rotation, etc), so if one of those symmetries doesn't hold in a curved space, the corresponding conservation law just doesn't hold.
Re: Robotic swimming in curved space via geometric phase
#10Does this also work for curved space time? Or is that type of curvature not going to help because it's relativistic? Or is the shape wrong? They mention that it doesn't work for cylinders.
The abstract says "the noncommutativity of translations permits translation without momentum exchange in either gravitationally curved spacetime or the curved surfaces encountered by locomotors in real-world environments."
The idea isn't new. This is an experimental verification of it in the case of curved surfaces, not gravitationally curved space, but it should work for both.