Can I use Robbe 3D gyros to stabilise a pan&Tilt?

[Ian in Cheshire]

I have two new unused Robbe 8065 gyros and would like to use them to make a self levelling or at least stabilised mount for a video camera.

The gyro instructions say it can set to be 'normal' or a 'heading hold' operation, the instructions to change over are as clear as mud though, and I'm not sure which I need anyway.

I have temporarily fastened a gyro to a output lever, connected two servo testers to the gyro inputs and it 'sort' of works. I can see some movement compensation taking place but its only just noticeable and if I increase the gain it becomes unstable.

Is my plan doomed to failures?

Ian

[Steve W-O]

It works with cheap servos, but they do have some drift.

Also if it is mounted on any type of vehicle, when you turn the vehicle, they will keep the camera facing the same way, not to the front of the vehicle.

It doesn't keep the camera very steady, it is a bit jerky.

[Ian in Cheshire]

Steve

I will use fast good quality servos, its whether the gyros I have are suitable that I was wondering about.

Drift should not be a problem. as its on a pan and tilt compensation for drift will be done by switching off every now and again when not recording video.

The sort of result I was hoping for is how cameras on UAVs keep the horizon level.

Ian

[Steve W-O]

I assume you will be using spare TX channels to control the camera.

It will work, I was trying it "on land" and it does not give the rock steady stabilisation of a BBC camera, maybe I was hoping for too much.

Can't answer for your specific gyros, but if they are headlock, they are sure to work roughly the same as another headlock gyro.

I have never seen a UAV video where the horizon is kept level (I don't look at many, so no surprise) but I imagine it would feel quite unnatural to have turn and no bank,

If you watch the control surfaces or servo connected to a gyro, you will see there are small movements, sometimes like an overshoot and correction,that aren't noticed in flight, but are noticed when a camera is attached, which is why it didn't give me the results I was hoping for, but being in different surroundings, it may be fine for your application

[Ian in Cheshire]

Steve

Thanks for your input, I am sure what I want can be done but maybe not as simply as I hoped (2 gyros, 2 servos and a few other bits).

I built a quadrocopter for a friend recently and that had a camera mount that kept the camera level as the copter tilted side to side (as plane dips one wing). Another servo tilted the camera up and down and that too was driven by a gyro so the tilt angle stayed the same relative to the ground.

My application is actually on a wheeled vehicle and was hoping to make it self contained so it would not need any of the Tx/Rx channels, Once setup I could feed it constant PWM signals from a small micro.

This one shows the sort of thing I am looking for.

http://hackedgadgets.com/2007/09/17/gyro-stabilized-camera/

Thanks

Ian

[Steve W-O]

Unless it is running on a very smooth surface, I don't think you would notice any slight movement.

I used cheap servo testers to supply the signal, and move the camera, could easily have used a pic8 similar to your suggestion.

My trial was a camera mounted on a long pole.

[Ian in Cheshire]

Posted by Steve W-O on 26/04/2012 08:33:06:

Unless it is running on a very smooth surface, I don't think you would notice any slight movement.

I used cheap servo testers to supply the signal, and move the camera, could easily have used a pic8 similar to your suggestion.

My trial was a camera mounted on a long pole.

The surface is smooth, but undulating. I suppose another way of keeping the camera level would be top have some form of self-levelling suspension but putting that on a model car sounds harder than controlling two servos.

Ian

[Steve W-O]

I think for your use it is worth giving it a try, as the objects in the picture will be moving, mine was not, so any slight movement was very obvious.

[Cyclicscooby]

If you have the gyro's as a 'self contained' unit, NOT connected to the Rx, then as you turn the vehicle, the 'Pan' will keep looking in the original direction..(original direction being the way it was pointing when you powered it up.. ) Not a problem for Tilt, as long as it's flat when powered up.

You need to connect the Pan gyro to the steering servo, via a Y-lead... OR.. add it to a spare channel and mix it in n out..

 

I made a NON-gyro'ed Pan n tilt for a car via a cheap (no good for flying) wireless cam..

Using a 6ch Tx, I controlled the car with 2 axis, and the camera with the other two (head-doing), BUT, I also had a mix, so at the flick of a switch, the Pan was connected to the steering, taking it out my hands and automatically looking where I steered...

 

If you watch the vid below, as I start, go thru the ditch then stop and look up the bank, i'm controlling the pan. Then I flicked the mix to slave the pan to the steering, and the camara follows the front wheel movement until the scene cut fade-out

 

I think, you'll need the Pan in Non-heading hold, Tilt in HH mode.. but they can be adjusted via the Tx if you have enuf channels..

 

HTH's

 

Luv

Chrisie.. xx

Edited By Cyclicscooby on 26/04/2012 11:46:51