Hello Robotis, I am using your motor Dynamixel XH series for my project Buliding 3 degree of freedom Robotic arm and it's showing that it used PID controller for controlling but when i Used with U2D2 communication converter with U2D2 power hub then it's c

[roboteer]

The PID Controller is built-in/coded inside the firmware for each ROBOTIS Dynamixel - not in the U2D2. For example the ROBOTIS e-manual provides the following information for the XH540-V270 and its PID coefficients when in Position Control mode:

ROBOTIS e-Manual

But watch out, the factory default values are usually only set for the P coefficient

ROBOTIS e-Manual

Have you seen the following two posts about PID tuning (just on a typical “bare” dynamixel):

DYNAMIXEL Tips | DYNAMIXEL Position Controller PID Gain Tuning (feat. Arduino example)

[DYNAMIXEL Tips | DYNAMIXEL Position Controller PID Gain Tuning (feat. Arduino example)] A quick tutorial produced by ROBOTIS’ OpenSource Team on tuning the PID values of your DYNAMIXEL servo. PID tuning is an important part of configuring your DYNAMIXELs, as it allows more precise and accurate execution of motions. For many first time users it sounds like a complex and daunting process, but thanks to the ROBOTIS OpenSource Team everyone can see how easy it really is!

PID Control Parameters Supplement

PID control is an extremely useful tool to fine tune the motion behavior of your DYNAMIXEL System, and the following video provides a good introduction to the basics of PID control. [PID Control Parameters] Although that video provides a strong starting point for understanding the parameters used in PID Control, I wanted to share some more information about PID control that I couldn’t fit in the video itself. System Behaviors There are a few behaviors that occur in every PID contr…