Im planning to build a drone payload to drop poison baits. If you can picture how a revolver pistol works this is similar.
baits will go into tubes which are in a circle about 10 in total, und the circle ring will be a plate that has a single hole in it so when it rotates at one tube at a time it will release a bait, Another press of a button it rotates to the next station and so on. the signal will be trigged by a PWM signal from a remote control.
Im thinking a stepper motor and a controller of some kind being a Arduino or a motor controller. It seems simple enough so shouldn’t be to tricky for you guys.
pretty much a single round plate with a hole needs to go to a certain position at each press of a button.
if you can come up with code would be a bonus as well.
What is the all important weight (kG) limit here before anyone gets carried away with design ideas.
The weight is not a huge factor, its a heavy lift drone but would be good to keep it under 5kg. I think my concept is the go but if anyone else has ideas of something different that’s cool, the baits are like small sausages about 10cm x 2cm.
OK so the baits are quite large. I was imagining something like 10mm diameter sphere.
If you are only going to have 1 bait in each tube your idea would probably work. But if more than one in each tube, stopping a second one coming down and coming out or stopping the wheel from turning to the next tube might be a bit of a problem and get quite cumbersome and add some weight.
A servo and ratchet would be simpler and lighter than a stepper. Your RC receiver might be able to drive the servo on a spare channel, so no controller needed.
An alternative is this device (mode 1): rcd3003.pdf (flashrc.com)
Interesting idea with a ratchet, but would be a bit of calculation to get the right size ratchet to reach each station. at least with the stepper motor it could be programmed easy enough to make each turn of 30 degrees for example. would I need Arduino or would a basic motor controller work like a pololu tic or jrk
The ratchet simply stops it moving backwards when the servo returns to zero. The distance moved with each drop is set by the position information passed to the servo.