Dobot M1 has two types of coordinate system, the joint one and the Cartesian one, as shown in Figure 2.3 and Figure 2.4 respectively.

&NOTE

The data shown in Figure 2.3 indicates the mechanical limitation.

Figure 2.3 Joint coordinate system

Figure 2.4 Cartesian coordinate system

Joint coordinate system: The coordinates are determined by the motion joints.

Dobot M1 contains four joints.

J1, J2, and J4 are the rotating joints, which are located and oriented in the horizontal plane. And their axes are parallel to each other. The positive direction of these joints is counter-clockwise.

J3 is the moving joint, which is used for the movement of the end effector in the perpendicular plane. The positive direction of J3 is vertical upward.

Cartesian coordinate system: The coordinates are determined by the base.

The origin is the axes center of the motor of Rear Arm where Rear Arm is dropped to the bottom of the Z-axis screw.

The direction of X-axis is perpendicular to the base forward.

The direction of Y-axis is perpendicular to the base leftward.

The direction of Z-axis is vertical upward, which is based on the right hand rule.

The R-axis is the attitude of the end center relative to the origin of the robotic arm, of which the positive direction is counter-clockwise. The R-coordinate is the sum of the coordinates of J1, J2 and J4.