Origin

Each manufacturer fix a origin point wherever he want. To have a plug and play arm we need that the origin wiil be the same for all the arms. Thats is why the first thing that the user has to do is to verify the origin, and if it is not in the good point it will change it thanks to a parameters.

Although the robots are totally different (surely the robot is not identical to those described in the images), you have to take into account that the arms follows the general structure. The following figure shows where the origin is place on:

Mandatory topics

x = the front (in case of not being well defined the front of the robot will be taken as the front the user sees more appropriate)

As you could see the image we can generalize it in three different groups:

  • Articulated, Scara, Cylindrical, Spherical: all have in common that they start from a base from which the whole robot has been built.
  • Cartesian: it is the robot that moves by rails (based mostly on linear servo motors) once the front is defined, the origin will be placed in the left rear part. The z-axis will be positive in the direction of the workspace. In case the workspace is in both directions (up and down) the positive will be down. The bridge canes are categorize like cartesian robots.
  • Parallel: the origin is placed in the center of the base, and the z-axis will look towards the end effector.

In case of placing the robot in another direction (for example, hanging it from the ceiling instead of fixing it on the ground) the axis will rotate with the robot.

The manufacturer explains where is the origin of the robot (different to the defined), so you have to change the origin with parameters.

change origin

Mandatory Parameter Value Unit Description
x_angle_y_direction - rad Turn the X axis in the direction where the Y axis is
x_angle_z_direction π/2 rad Turn the X axis in the direction where the Z axis is
y_angle_x_direction - rad Turn the Y axis in the direction where the X axis is
y_angle_z_direction π/2 rad Turn the Y axis in the direction where the Z axis is
z_direction false true/false T: the z-axis direction is okey/F: reverse direction
x_position -0.22 m X axis position according to the marked origin
y_position -0.34 m Y axis position according to the marked origin
z_position 0.0 m Z axis position according to the marked origin

taking into account that the first damage the following