Connectors that protect wires from breaking when it is resonating alot
You should stop everything flapping about.  In high vibration environments (aerospace, etc), you'd find everything tied or laced in some way to stop it shaking.  You might even find that the lacing has then had epoxy or some other sticky goop put on it to stiffen it further.

Making everything stiffer will also raise the resonant frequency of the whole system, which may be helpful too.

Here's a picture of the ultimate in robot vehicles for hostile environments (Curiosity) - note the lacing on the cables...