Pypot light version?

I am preparing a new show with Poppy humanoïd in less than 1 month. My Poppy humanoïd was using the old ODROID U3 which is the faster to send orders to all the motors.
The first one I had died one year ago but the second one (last) died last friday.
As the ODROID U3 has no support… pure moment of panic :frowning:
So, I have to switch to Raspberry Pi 3B+ and I always have the issue about lag on the serial port. I have to really solve this issue. I did some tests :

  • plug the Poppy on a laptop with Windows 10 : no lag => the issue is due to computer, not due to motors or wires
  • plug only two motor : very small lag => it may be due to the number of motors
  • changed to /boot/cmdline.txt with dwc_otg.speed=1 => same lag

The command I use the pilot the robot is this single script :

I just update the position of each motors at 50Hz.

I did a new test with the new dynamixel SDK :
and only two motors, there is no lag with respect to pypot.

To confirm I will convert my script using dynamixel SDK.
For information, this SDK can pilot protocol V1.0 and V2.0 on the same serial port.

I also had dependencies issues while installing pypot because it needs scipy with python 3.6. I know python 2.7 will no longer be maintained but for the moment, I cannot install pypot… double panic :frowning:

Could it be possible to isolate the serial communication with dynamixel, is it a bad idea ?

Hello Thomas,
not really an answer to your technical question about dynamixel, but I have 2 cards ODROID U3 left at ENSAM. The cards are working, I can give you these cards if it can help (answer me on my email adresse at ensam…).

Thank you very much :slight_smile: