Ambitious Gimbal Project

I've taken up the plan to create my own gyrostabilized gimbal with Geo-pointing possibilities. I know what I want but I'm not really sure what components I need to start with.
Here's my plan:

  • The gimbal will be 2 axis and will be driven by two 30V, 30W brushless DC motors. The motors have optical encoders so they give feedback on the position and number of rotations.
  • Each axis has to be stabilized by a gyro.
  • Own position will be based upon IMU + GPS input
  • I want to steer the camera on the gimbal to look at a waypoint, so from the input of a waypoint (preferably in MGRS) I want to steer the gimbal to an angle and heading, always related from my own (changing) position and heading.

What do I think I need:

  • Motor controller with sufficient power
  • Gyro
  • IMU
  • GPS
  • Element to read encoder
  • element to tie this all together and get it working (Arduino, but which one?)

I hope someone can help me off to a good start
Koen

Do some research on gimbal lock first

Nick

This sounds like a really neat project. I don't think that arduinos will be fast enough to do all of the processing though. I hope I'm wrong, though. We'll see what the gurus have to say about that.

Aside from that, I have some questions. Why does the gimbal need to be gyro-controlled? That is what you meant, right? Control the angle/orientation by adjusting the speed of the gyros? Or did you mean gyro sensors? Would it be easier to use necessary sensors(IMU?) to determine orientation, then move stepper motors or servos to change the orientation? Are you a mechanical engineer?

@ P_Wood: No I'm mechanical engineer. A flying enthousiast with a crack for smooth working electronics fits better.
Regarding your questions, the gyro controls will stabilize the platform, in the same manner they sabilize RC helicopters. I' don't know wether I'll be able to use the IMU gyro input to do that, but when looking at the price for a single gyro I don't think I would bother to separate the gyro input from the IMU feedback.

@nickle: Since I only want stabilization on two axes, I don't see why gimbal lock should occur. In the IMU it might happen, but the IMU will be corrected by a 10 Hz GPS input. The gimbal itself will work from a constant altitude. Therefor I would say, the problem should be solvable. At any given moment you know two positions in three dimensions. The calculation comes down to telling the gimbal a heading and attitude toward an other waypoint. My Garmin GPS is capable of doing this with ease in two dimensions. Adding a third dimension should not be too big a problem? Or am I cutting corners?

Koen