Holio

Up

Holio is my response to a friends curiosity. He has a hole on his property out in the country. It's too small (or we're too big) to enter directly. Holes are everywhere but this one is special. For reasons unknown to anyone, it steams in the winter. It's no where near any identifiable gas, steam or other buried lines so, it needs to be investigated. Attempts were made to lower camera's on timers but the results were disappointing. With no way to control the orientation of the camera, close-ups of rock walls were plentiful.  So I built what is little more than a motion base and a camera on a pan & tilt. It has two white LED's for headlights and it's driven by an 8 conductor (Ethernet) cable. The cable provides power and commands via 9600 baud serial and brings back a video signal from the camera.

It has no onboard smarts and it's very slow. Since we are exploring a hole the devise ultimately needed a tether anyway so I thought this could effectively serve as an umbilical as well.

Changes Pending & Comments:

  1. I think the pan and tilt is pretty cool but it's just too much for this little RPV, I think I might go to a simpler design.

  2. This is the first time I have used servo motors in a continuous mode for drive wheels. I'd always figured them to be too expensive to cut up but until now, I never really stopped to think about what a good deal they are. In a neat compact form factor that is easily mountable you get a transmission, motor and a reversible speed controller. Not bad for $25.

  3. It sits too low across the bottom with the protective hood on. Bigger wheels are a necessity but will be limited by the proximity of the axels.

  4. The Pontech servo driver, like most others, is very susceptible to power sags when spinning servos. In this case it's a real problem due to the long umbilical wires and low current available through small wires. To counter this problem, I installed an independent 9v battery for the servo controller.

I'll update this one when it gets finished.

 Hit Counter


Last updated: 01/05/09.