Potential issue with dc control box and joint range check

[IrvingF7]

Hi! Thanks for open-sourcing this.

I use a xArm 6 with a DC control box, and I noticed that I cannot set servo angles.

The issue is this line

device_type = int('{}1305'.format(self.axis)) if self.sn and int(self.sn[2:6]) >= 1305 and int(self.sn[2:6]) < 8500 else self.device_type

Basically, maybe because I am using a DC control box, my robot doesn't seem to have a sn in the eyes of this SDK, so self.sn would be an empty string, and would cause an error when converted to an int.

In most other places, self.sn would be checked against isdigit (I will find some examples later), which leads me to believe this is a small bug. I made some modifications to let `device_type = self.device_type directly, and after that servo angle works fine

But maybe I am missing something or doing something wrong. In that case, I would really appreciate it if you can let me know

Cheers

[penglongxiang]

Hi, Could you please provide the actual Serial Number attached at the robot base? And also please download the log package through Studio at Settings->My Device->log->Download, you may sent it to jason@ufactory.cc. We will help diagnose the cause.

[IrvingF7]

Hi, Could you please provide the actual Serial Number attached at the robot base? And also please download the log package through Studio at Settings->My Device->log->Download, you may sent it to jason@ufactory.cc. We will help diagnose the cause.

Thanks for the prompt reply. I will do that when I got back to the lab. Meanwhile, if you look at this line in x3/base.py, it does a very similar thing but says

self._arm_type_is_1300 = int(xarm_sn[2:6]) >= 1300 if xarm_sn[2:6].isdigit() else False, so I just did something similar to make sure sn is not an empty string, and was able to by pass this error. Is the original code in x3/xarm.py not a bug?

[penglongxiang]

Hi, we have to check the log to see why the sn extracted by SDK is empty (this seems to be the major issue) and also help us to confirm if a logic bug exist or not. Bypassing the error may not be a safe workaround. Please provide the log to us first to better confirm the cause. Thanks.