Reply To: Regarding GRBL

#1141 Quote
Angel LM
Admin

Hi Burcu!

I’m happy to know that the motors are working now, what was the problem?

Regarding the home position question, do you have any position sensor in your Thor? In my case (the current design in my repository), Thor has 5 sensors (on the 5 first articulations) to set the home position when the board is connected (or the $h command is sent).

If yours have not sensors this would the sequence:

  • When the Arduino Mega is connected to the PC it assumes that the current position is the home position (A=0º, B=0º, C=0º… and so on)
  • When the connection is established between the Arduino Mega and the GCode sender program, the current position is set as home position (A=0º, B=0º, C=0º… and so on) <- This happens everytime you close and open the serial connection
  • When the connection is established and you send a GCode the motors will move considering the home position.

If it has sensors this would the sequence:

  • When the
    Arduino Mega is connected to the PC the robot will start the home sequence, moving its articulations until them reach the home position (A=0º, B=0º, C=0º… and so on)
  • When the
    connection is established between the Arduino Mega and the GCode sender
    program, the robot will start the home sequence, moving its articulations until
    them reach the home position (A=0º, B=0º, C=0º… and so on) <- This happens everytime you close and open the
    serial connection
  • When the connection is established and you send a GCode the motors will move considering the home position.

In both cases, sending a single command should work…

Can you share the GCode you are trying to send? I’ll try to replicate the issue.

Just in case, there are a GCode command that switches between Absolute Positioning and Relative Positioning that may be the cause of that problem.