Asked — Edited

Servo Movement


I am using multiple HS-805bb Servos. I can not seem to get full 180 degree movement using the servo controller. Is there another controller that works better? See image for specs on this... it seems I need to give it a longer pulse?

User-inserted image

Skip to comments


Upgrade to ARC Pro

Experience early access to the latest features and updates. You'll have everything that is needed to unleash your robot's potential.

United Kingdom

The EZ-B will move the servo from the 0 position to the 180 position, these are not necessarily degrees as it can vary between servos. If your servo is not moving to the desired position when you set it to either 0 or 180 (0 or 100 in old versions) then the problem lies with the servo not the software or the EZ-B.


Ok but it doesn't seem I am getting full movement.. only to 90 degrees.

United Kingdom

Is the control in ARC set up correctly to allow full movement?

If ARC's servo control is set to 0 then the servo will be at the lowest position, if set to 180 it will be set to the servos highest position.


Hi @jackphillips what version of the software are you using? Have you upgraded lately?


In any servo Config Menu...

  • Set the Min value of the servo to 1
  • Set the Max value of the servo to 100

Now when you use that servo, you can move the servo position between 1 and 100. If the servo does not move the full range, it is because the servo pulse is too small for that unusual servo type. As the instructions in their manual says, you may need a servo stretcher:)

Leave it to HiTech to change the way servos work:P


Hi DJ, Look like it needs more than that and servo needs pulled apart and adapted... I will try one and let you know. They have a way on there web site disassemble and change the config on that relay... If I mess up $40 down the drain.


Do you have a cheap standard servo to test? That way you can at least eliminate ARC as the problem...



I constructed and installed the Shoulder and Bicep to 3 relays. At first I could not get the relays (HS-805BB) to rotate more than 180 degrees. I opened the relays as suggested on InMoov site, cut the stops and removed the potentiometers. I did this on 2 relays, not the 3rd. That one I just took the connector out so that it could use the potentiometer. The other 2 I left hanging out for now. I was able go in either redirection as much as I want by just pulsing it as many times as need to move the relay where I wanted to go. I do not know how or if possible to find a certain position to place the servo. Any one with ideas let me know.