07-12-2016, 10:48 PM
Omnidirectional thrust?
If this is using propellant of any kind, absolutely disgusting from an engineering standpoint. You waste a TON of fuel operating a main engine at all, but then trying to divert its exhaust sideways in any way results in the center of thrust not being aligned with the center of mass- and a craft that just wants to spin uncontrollably.
Discrete thruster components are a far better solution because then you only burn exactly as much fuel as you need to do the job, and can align these thrusters such that the center of thrust is always concentric with the center of mass so that the craft moves in the direction you want it to without requiring counter-thrust to balance it or compensate for it.
And that's not even considering the mass or complexity of the plumbing needed to divert hot exhaust at steel-melting temperatures through a ship that is already struggling to get rid of heat so that it can come out in the correct location to avoid sending the craft into an uncontrolled spiral.
Now if you're using a propellantless thruster like the one NASA is playing with, then yes you could make omnidirectional thrust by simply mounting the thruster unit in a way that it can rotate in all 3 axis of motion and push the ship in any direction you want. Combine that with reaction wheels to orient the thruster relative to the ship, and you can fly or rotate in any direction at any time.
If this is using propellant of any kind, absolutely disgusting from an engineering standpoint. You waste a TON of fuel operating a main engine at all, but then trying to divert its exhaust sideways in any way results in the center of thrust not being aligned with the center of mass- and a craft that just wants to spin uncontrollably.
Discrete thruster components are a far better solution because then you only burn exactly as much fuel as you need to do the job, and can align these thrusters such that the center of thrust is always concentric with the center of mass so that the craft moves in the direction you want it to without requiring counter-thrust to balance it or compensate for it.
And that's not even considering the mass or complexity of the plumbing needed to divert hot exhaust at steel-melting temperatures through a ship that is already struggling to get rid of heat so that it can come out in the correct location to avoid sending the craft into an uncontrolled spiral.
Now if you're using a propellantless thruster like the one NASA is playing with, then yes you could make omnidirectional thrust by simply mounting the thruster unit in a way that it can rotate in all 3 axis of motion and push the ship in any direction you want. Combine that with reaction wheels to orient the thruster relative to the ship, and you can fly or rotate in any direction at any time.
Feel free to PM me if anything is broken