Servo turret rotation issue

[Peter386]

Greetings!

I have an issue that I thought you guys could help me out with.

I have a Heng Long T-90 that I upgraded with ElMod Fusion Pro. This new board has a specific connection for my brand of RC tanks 'Turret controls', very convenient! However, I modified my RC Tanks main gun to recoil upon shooting via 3D printed parts and servos. I use a servo for gun elevation as well. This being said, I can no longer use the special turret connection on the motherboard to control the original DC motor for turret rotation as there is no way to control the polarity of the DC motor(that i know of yet) hence the turret only spins in one direction. My new motherboard for the RC tank can control 3 servos, 2 have already been assigned the gun recoil and gun elevation, the 3rd is for 360 degree turret rotation.

I bought the Analog Hitec Micro HS-85MG+ (29x13x30mm) and did the potentiometer modification for continuous rotation. I glued the potentiometer in place in the neutral position and removed the necessary little plastic gear to obtain this. It works and rotates 360 degrees in both directions. It is now mounted and able to rotate the turret of the RC Tank.

Now for the issue: when I rotate the servo in any given direction, in order for it to stop rotating, I must give it the same signal in the opposite direction with my radio in order for it to stop rotating. Another way to put it is that I must 'counter steer' in the opposite direction for it to come to a complete stop and start rotating again. What I wan't is for the servo to stop rotating when my radios stick is in the neutral position (An adjustment to get the servo to stop when stick is centered). Otherwise I actually have very little control of the turret and have the risk of damaging parts and inside components of my Model RC Tank.

Question: What options do I have to rectify this issue? If I purchase a Hitec Digital HS-5087MH (29x13x30) servo along with the DPC-10 Servo Programmer, and modify the Digital servo for continuous rotation, will I be able to program it to get the servo to stop when the controllers stick is centered?

I thank you for your time and patience in this matter as I am relativity new to RC and the world of servos. It is not out of my scope however to do whatever is necessary to get this to work (ie: soldering resistors in place of potentiometer for example) and I can provide any further information that you may need and you have my fullest cooperation in this matter. Thank You!

Best reguards,

-Peter Engberg.

[BarryC]

Hi Peter,

I had a similar issue when I used a servo for turret rotation and the ElMod F Pro.

Here is the answer I received from Thomas of ElMod. Perhaps it is the answer to your issue.

Hello Barry!

You use the wrong function for horizontal positioning. You need the function "turret rotation (ESC)“, not „turret rotation“ which is meant for pure servo, not servos used as motor.

Best regards,
Thomas

ElMod, Thomas Kusch
Banater Str. 19
78054 Villingen-Schwenningen
GERMANY
info@elmod.eu