Results 1 to 3 of 3

Thread: Cable steering, one servo or two?

  1. #1
    Join Date
    Aug 2017
    Location
    OZ
    Posts
    686

    Default Cable steering, one servo or two?

    I am setting up a large mono hull with an outdrive with cable operated "prototypical" steering. The cables enter the transom 140mm apart from each other. To connect to a single servo with a long actuating arm would severely limit the torque applied at the point the cable connects to the servo arm. Bringing the servo ends of the cables closer together would cause a sharp radius on the cables and the stiff outer tubing. Is it possible to use two servos, one controlling each cable, thus keeping the cable run reasonably straight?

    To use two quarter scale servos would raise a few questions:
    Would the servos fight against each other setting up additional tension in the cable movement?
    Would the receiver have the ability to power two quarter scale servos? Power to the receiver would be a 2200 mah LiFe 2s battery. I have heard of a wye cable connection for a servo that bypasses the power drain of the servo around the receiver but do not know if such a cable is available commercially or needs to be fabricated.

    I am not worried about the weight of two large servos as to achieve a CoG of around 26 - 28% is going to take a bit of juggling and I need all the weight behind the motor.

    Edit: a bit of searching on the Arrow Shark Marine site shows the Arneson cable actuation using two standard size servos with the servos interconnected with a pushrod.
    Last edited by Old School; 04-09-2021 at 06:49 PM. Reason: Additional info

  2. #2
    Join Date
    Mar 2011
    Location
    BC
    Posts
    7,629

    Default

    As long as you don’t have any non matching angles on the two pushrod/servo geometry it should be fine. As far as power consumption goes two servos shouldn’t really take any more juice than one(unless geometry is out of whack).
    It should simply take ‘X’ amount of torque to push the drive one way or another, one or two servos will just supply that torque.

  3. #3
    Join Date
    Aug 2017
    Location
    OZ
    Posts
    686

    Default

    Thankyou. I have decided to go with two high torque standard digital servos with an interconnect bar between. This is how Arrow Shark does it with their Arneson drive.

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •