ORIGINAL: jim pettis
Looks good so far...just don't forget to add a torque limiter or such so that if the gear do hang up somehow, they shut down rather than burn out...or is that what you mean when you mention a current sensing circuit?
Jim,
Yes.... my idea of a current sensor (built into H-bridge chip I plan to use) will hopefully allow me to sense increase current at both ends of throw... motor would hence stop automatically. It would also stop any time it senses an increase in current due to unexpected binding (i.e. obstacle). I ordered a sample chip ([link=http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MC33887&fsrch=1]Freescale MC33887[/link]) and will experiment more when it comes in. Some PIC code will also have to be written but should not be all too difficult... so I hope!
Right now, I'm thinking of seperating the controller from the mechanism... not only to save space in/on the retract, but to also protect the controller from the elements, sheilding it inside the aircraft. Plus it probably wouldn't be too hard to have one servo controller board control MANY servos for various applications (maybe even with onboard options such as speed, stagger, delay, etc... functions). I also pondered the idea of auto retracts where when the aircraft (controller) senses altitude (via sensor) and when a preset altitude is reached, the retracts automatically are triggered, bringing up the gear.
I am more of a small DIY parts guy (supply small elec gadgets, kit parts, etc...) so if any one else is interested is a possible partnership of some type... please PM.