Driver related

1 About python

Q: What do the parameters in send_coords([x,y,z,rx,ry,rz], speed, 1) mean? What do rx, ry, and rz correspond to in Euler angles? What is the rotation order of Euler angles? And what is the value range of each parameter?

• A: The parameters in the previous array are the end coordinates of the robot arm, speed is the speed, and the last parameter is the motion mode. rx, ry, and rz should correspond to rpy, which means roll, pitch, and yaw respectively. The order of Euler angles is zyx, and zyx is the local coordinate. The value range of X, Y, and Z is -300 to 300.00 (the value range is undefined, and the inverse kinematics no solution prompt will be returned if it exceeds the range), and the value range of rx, ry, and rz is -180 to 180.

Q: Are sample tutorials for the python API available?

• A: Currently there is a demo. There is a test code in the Test folder of github. You can execute it with the terminal. https://github.com/elephantrobotics/pymycobot/tree/main/demo

Q: Are the python APIs of different versions of the robot arm the same?

• A: The API is the same.

2 About ROS

Q: How do microcontroller-based and microprocessor-based robot arms run ROS?

• A: The microcontroller-based robot arm is currently on Ubuntu. We need to download a virtual machine to build a virtual environment and install the Ubuntu system in the virtual environment to run ROS. You can also develop your own ROS. The microprocessor-based robotic arm comes with a ROS environment and can be used directly.

Q: Can the microprocessor-based robotic arm be connected to a PC to use ros and moveit?

• A: The current open source data does not have direct communication control. It can be implemented by modifying the existing node files through ros + socket.

Q: Can you provide rviz model files and programming examples?

• A: They are provided on our github. https://github.com/elephantrobotics/mycobot_ros

Q: When using ROS to start the rviz model file, why does it report an error permission denied: '/dev/ttyUSB0'?

• A: It is because the serial port permission is not given. You should enter sudo chmod 777 port name in the terminal.

Q: When running the slider control and model following commands of ROS, why is the error init() takes exactly 2 arguments (3 given) reported?

• A: The pymycobot library is not installed and started.

Q: When using ROS, why is the robot arm angle inconsistent with the model angle after opening the rviz model?

• A: It is likely that the zero position of the robot arm is not calibrated, and the zero position of the robot arm needs to be calibrated.