If it's a lot like this - http://www.servocity.com/html/hs-5755mg_servo.html
it wouldn't use a drum. Just fit an extension to the horn supplied to make it the right length to give the throw required.
Is there a pressing need for a digital servo as opposed to a normal heavy duty one?
That servo would normally be used as an arm winch, programmed for 180 degrees rotation. It can be modified for continuous rotation and a drum added, but why do that extra work?
The drum dia will depend upon the length of sheet line that you need to move, and the number of turns you want, More turns allows a smaller drum and more torque, but increases travel time.
Note that the servo uses the large 'D' size spline.
You can calculate the length of main sheet to be moved by the winch. Assume that the boom going from close hauled to full out to the shrouds, creates a 90 degree angle, then the length of the sheet line is the hypotenuse, and the base and side are the distance from the goose neck to the main boom attachment point - call it L.
the diameter of the drum is square root of (L squared*2) divided by Pi- divided by number of revolutions desired.
For example, Gooseneck to main sheet attach point L = 200mm, Three revolutions required
L squared (200*200) = 40000 times 2 = 80000
Length of main sheet movement is Sq root of 80000 = 282.8mm
Divide by 3.14 =90
Divide by 3 revolutions = 30mm
So the diameter of the drum is 30mm
Last edited by hiljoball; Dec 09, 2012 at 10:22 AM.
|Category||Thread||Thread Starter||Forum||Replies||Last Post|
|Sold||Hyperion Digital DS-12 Digital Servos||QuietRCFly||Aircraft - General - Radio Equipment (FS/W)||4||Sep 16, 2012 07:31 PM|
|Sold||3 Hitec Digital 5065MG cyclic servos, 1 5084MG Digital tail servo Price reduced||Sky_Dancer||Aircraft - General - Radio Equipment (FS/W)||2||May 19, 2012 11:17 AM|
|Sold||Hitec Digital 5065MG cyclic servos, 5084MG Digital tail servo||Sky_Dancer||Aircraft - Electric - Helis (FS/W)||1||May 18, 2012 03:04 PM|
|Discussion||Servo Glitching Corona 919mg digital servo||mick3485||Radios||5||Mar 21, 2012 03:04 PM|
|Sold||Digital Servos (Metal Gear Micro Servo)||ShokWaveRider||Aircraft - General - Radio Equipment (FS/W)||2||Mar 18, 2012 02:49 PM|