Pan/Tilt from DAGU parts

By ignoblegnome
@ August 21, 2009

• Actuators / output devices: 2 Dagu mini servos
• Control method: Picaxe 28x1, but it should work on anything that can drive two servos
• Power source: 6V

I decided to build a pan/tilt mount using the DAGU parts I recently received. I did have a little trouble, but overall I'm pleased with the result.  You may notice some odd servo behavior in the video, This is due to the trouble I mentioned. I over-rotated the pan servo.  It'll never be the same. ; j

The lower servo controls the pan mostion. It is held in a clamp for testing. It is screwed to the nicely spaced mounting holes on the LMR branded DAGU sensor bracket.

You can see the upper servo, which controls tilt motion, in the picture above. A machine screw holds the right side of the two brackets together. I used two nuts tightened against each other to prevent this link from binding. I didn't know if I would need to insert some small washers to help keep the parts moving freely. As it turned out, I didn't need them.

The servo horn is hot glued in place to the inside surface of the upper bracket. I used the round horn from the pack that came with the servo, for maximum surface area for the glue joint. I filled the curved slot from the outer surface of the top bracket with hot glue too, and then used a razor to make sure it was flush so it would't catch. The screw provided for attaching the servo horns mounts through the two round pivot holes to form the left side of the hinge.

Youl'll also notice the little block of wood hot glued in place. This keeps the tilt servo body from rotating relative to the lower bracket.

I might attach some of these parts more firmly in the future, but for the prototype I didn't want to drill any new holes in the brackets, or do anything I couldn't un-do easily. I would have liked some easier way to connect the servo horn to the pivot point of the two brackets. This is an obvious failure point I will want to strengthen.

The PICAXE Basic code that is demonstrated in the video is attached. There are some sound samples in there too. I tried to recreate the Volga Boatmen Song, without much fidelity. I had better luck with the tune from "Close Encounters of the 3rd Kind".