hey guys,
just thought I would show of one of my latest efforts.A servo hacked continuous, controlled by a maple reading a 12 bit absolute encoder controlled to move to any absolute position.
the encoder is a AS5045 read by a maple dev board. working on an open source continuous rotation gimbal to go with the techpod, avalable for pre-order @ http://hobbyuav.com/
Comments
todd,
yes I think JR or one of the other big servo companies make something similar to this as well. You would have to reflash new firmware I would think to get it working 360. One advantage to using a PWM controlled H-bridge is the simplicity of the control loop. I have thought about getting one and breaking out the encoder but replacing the circuit board with a continuous rotation board. needs further investigation.
thanks
wayne
Is this similar to the magnetic encoder used on servos like the Hobbyking HK47110DMG? I had some of these servos at one time. Could there be a way to hack these servos to give them full 360 degree capability? There is no stop on the MI pot like traditional pots, but I never took one apart to observe the differences between the two.
Thanks, they are nothing new but I want to use them in a simpler less expensive way.
@Monroe
Ya open there is the code right there. Jr or futaba or hi tech(I forget) is currently using these internally to replace the pot in some of their high end servos.
@martin
Using a magnet I had laying around. Nothing specia
@Leonardo
Check out the video. I did exactly what you plan to do. No have not tested any slip ring yet
@R_lefebvr
That is pretty much the idea.
Yes, wouldn't this greatly simplify tracker construction and setup? Put a magnetometer on the tracking head, 360 servo/motor on the pan. Then just you just plunk it anywhere on the ground and it automatically can find the right direction?
Hi Wayne
I'm working on a continuous rotation gimbal as well. I got some AVR code working for reading the AS5040 and AS5045 and I'm waiting for the gears I bough to arrive so I can continue working on it. I was not planning to modify the servo as the breakouts I bough from http://www.madscientisthut.com/ are too big to fit inside the servo and was going to glue the magnet on top of the gear attached to the servo and place the sensor above the gear, but I may change that if you've found a simple solution for that. How are you doing it?
What about the camera wires? Are you using a slip ring? What kind? I'm using a capsule slip ring, but I'm not sure how well it will be able to transmit the signal. Did you test it?
Someone else did this about a year ago. it's good for an antenna tracker. getting the proper magnet is a pia.
Monroe, I read that somebody had done that at some point, maybe Futaba? But I think it didn't work out so well. I'm not sure if it was just the implementation.
Nice little chip...what kind of magnet did you use?