qtip67t

Wondering if anyone would have an idea or plans on converting and old R/C servo that would have the ability to rotate 360 degrees in either directions using channel 6 (3 position toggle switch on the TX). I want to be able to make a rotating mount for my wireless video cam and mount it to one of my R/C aircraft.
Any ideas would be greatly appreciated.

John
Independence, OR

redfox435cat

I don't know about 360 but a standard could be converted to 180 for about 25 cents

I'd have to look it up but I think the resistor values are 1K

put a 1/4 watt 1K resistor between the first and third poles of the potetiometer inside the servo careful to not mess with the alighnment of the pot. It wil now turn 180 degrees

qtip67t

Can a person replace the "pot" with a 360, if they make such an animal?

redfox435cat

You could. the problem is finding a pot with the right values to facilitate the right feedback current to hold position, can turn 360 which could be done posably with a 2 turn pot and be able to fit and line up correcly inside the output gear of the servo. Good luck there I'm sure some might know. By playing with the resistor values that I've show above you could incease the output to posably 270 degrees which is all I would recommend. If this is for a camera, if you go anymore than that your going to screw up the wiring

I don't have a schematic but what I've seen done is getting a park flyer motor very weak motor will do, with a pinion gear using the controler from it rigged to a circular plywood plate with the edges gears, the guy was able to slowly rotate the platform by bumping the motor forward or revers.

Pup Cam

The movement on a standard servo eg Futaba 148 is physically restricted by a mechanical stop that operates on the output gear and the fact that the internal feedback pot is limited to (the standard) 270 degrees. In order to provide greater rotation you need to remove the internal pot and the mechanical stop (a peg) and provide an external feed back system in the form of a multiturn pot (normally 10 turn) and connecting it to the output disc via gears, pulleys etc If I remember correctly Futaba servos use a 5.6K pot and normally provide about 180 degrees of rotation. This means that the change in resistance end to end is about 3.8K. The gearing therefore needs to provide this change of resistance for the number of degrees rotation you require. By the way, you should use a pot of the same value or slightly greater. Assuming you use a 10 turn 5.6K pot you need ~2/3 of 10 turns say 6 turns. Then if you want 1 complete turn of the output in each direction of stick movement ie 2 turns end to end you need gears/pulleys in the ratio of 2:6 between the pot and the servo output shaft. Of course by varying the ratios you can get any amount of rotation you want. The latest version of my pan and tilt system gives +/- 270 degrees of pan rotation using a 148 servo. You can see the first version on my website, pictures of the Mk 2 will ba along sometime soon. Perhaps it would be useful for me to put this info on the site next time I update it.

http://uk.geocities.com/tulyar@btint.../PilotCam1.htm

By the way you will need to be able to use a soldering iron fairly well in order to attach the 3 wires to the small pads on the servo amp where the old pot was to connect to the new external pot. You will also need to get the pot track connections the right way round (you will know if you got it wrong as the servo will keep rotating until it reaches the end stop of the new pot at which point it will stall so disconnect immediately!)

Good luck

qtip67t

Wow, it looks like I might be over my head on this one. I checked your site out and your videos look great.
I will try and give a shot. Thanks for the information.
John

Pup Cam

I have added some more detailed information on how to get more movement from a servo to my website at http://uk.geocities.com/[email protected]/ServoMod.htm if anyone is interested.

mklarich

How big an airplane are you looking at putting this in?

Matt

qtip67t

I have an Aerostar 40 with a Saito 50 and a Telemaster 150 (150 inch wingspan) capable of carrying up to 40 pounds.

acam37

My Feedback: (16)

Here is a link to a camera setup like you described. I saw this plane fly and the video system is the best I've seen yet.

http://www.rccombat.com/forum/topic....Terms=cam,ship