Tilting them vertical or nearly so is very useful if there could be any hail, that might be a good idea to support.

What about compressed air? It might not be too hard to find a small brushless low power air pump that could drive pistons directly.

You could mount the pump controller onto the back of the panels and use an accelerometer to measure angle, and run the pump until it's where you want it.

You'd probably need to do some testing and make sure it couldn't get jammed, then build up pressure, then suddenly unstick and move unsafely.