Is it possible to measure "Present Current" while operating in velocity control mode?

[abdur78]

ISSUE TEMPLATE ver. 1.2.0

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1. Which DYNAMIXEL SDK version do you use?

   • 3.7.51

2. Which programming language/tool do you use?

   • C, C++, C#, Python, Java, MATLAB, LABVIEW, ROS, Arduino, etc

3. Which operating system do you use?

   • Linux 22.04

4. Which USB serial converter do you use?

   • OpenCR

5. Which DYNAMIXEL do you use?

   • XM430-W350-T

6. Have you searched the issue from the closed issue threads? Yes

7. Please describe the issue in detail I have a special case scenario. I am currently operating the motor in velocity control mode. I need to detect the forces acting on my motor in velocity control mode i.e. detect the changing load on the motor while moving. In my view, this can be achieved through current/torque measurements while maintaining velocity. When i read the register of "Present Current" in velocity control mode, it is giving some garbage values. Is it possible to measure the current consumed by motor in velocity control mode?

Another idea I got was to shift between velocity control mode and current control mode several times while executing the program. However, since the EEPROMs usually have a limited number of write cycles, will it effect the life of my motor. My plan was to shift to current control mode after every few seconds, log the current value, and switch back to velocity control mode. Is it okay to use such an approach or will it significantly reduce the life of my motor.

Any other ideas and recommendations of achieving this task are highly appreciated.

8. How can we reproduce the issue?

[shiba-8ro]

@abdur78 Hi, The XM430 returns Present current even in Velocity control mode. First, check with Dynamixel Wizard 2.0 to see if your XM430 is working properly and it's the latest FW. I was able to get a graph of current values with Dynamixel Wizard 2.0.