Acceleration While Rotating

[Mantis Toboggan]

While I was rotating a 300+ part craft, made up of multiple docked sections, and while rotating either with reaction wheels or RCS, the entire craft shakes, and while trying to speed up time to make it stationary, the UI tells me that I cannot do that while the ship is under acceleration.

[Taki117]

Your craft is likely under acceleration due to the reaction wheels attempting to stop your rotation. Give it a second and try again.

[Markus Reese]

As above. The shaking is due to kinetic resonance to be overly technical. One of KSP's little technical treats is that non thrust force is applied solely at a module. So what happens is if you have a strong reaction wheel force, the force will apply itself at that module first causing it to flex. Much like grabbing a flimsy ruler then swinging it. This builds a spring force in the rocket and the opposite end of your module force will spring down, and it just starts reverberating. Solutions are opposite end reaction wheels (which can be clumsy to fit to the bottom of boosters, but using the side attachment node thing can help) or by adding more struts.

To stabilize with a blip of time warp, make sure all engines are off, and turn off your SAS system. the ASAS in large rockets can cause a wobble by alternating the force back and forth. If off for a second, your rocket should start a slow rotation, but once you blip time warp, it will stop since physics calculations will cease.