Clarify different ur type (#14)

* my_robot_cell_description: Add ur_type option to view_robot.launch.py

* Add a note to the documentation that the kinematics_params_file has to be changed

When changing the ur_type.

Author: urfeex

my_robot_cell/doc/start_ur_driver.rst

@@ -131,3 +131,15 @@ Or to use it with a real robot:
 
     #start the driver with real hardware
     ros2 launch my_robot_cell_control start_robot.launch.py
+
+.. note::
+   We extracted the calibration information from the robot and saved it in the
+   ``my_robot_cell_control`` package. If you have a different robot, you need to extract the
+   calibration information from that, and pass that to the launch file. Changing the ``ur_type``
+   parameter only will lead to a wrong model, as it will still be using the example kinematics from
+   a UR20. To use a UR5e, for example, you can do
+
+   .. code-block:: bash
+
+      ros2 launch my_robot_cell_control start_robot.launch.py ur_type:=ur5e use_mock_hardware:=true \
+        kinematics_parameters_file:=$(ros2 pkg prefix ur_description)/share/ur_description/config/ur5e/default_kinematics.yaml

my_robot_cell/my_robot_cell_description/launch/view_robot.launch.py

@@ -1,20 +1,22 @@
 from launch import LaunchDescription
-from launch.substitutions import Command, PathJoinSubstitution
+from launch.actions import DeclareLaunchArgument
+from launch.substitutions import Command, PathJoinSubstitution, LaunchConfiguration
 
 from launch_ros.actions import Node
 from launch_ros.parameter_descriptions import ParameterValue
 from launch_ros.substitutions import FindPackageShare
 
 
 def generate_launch_description():
+    ur_type = LaunchConfiguration("ur_type")
     description_package = FindPackageShare("my_robot_cell_description")
     description_file = PathJoinSubstitution(
         [description_package, "urdf", "my_robot_cell.urdf.xacro"]
     )
     rvizconfig_file = PathJoinSubstitution([description_package, "rviz", "urdf.rviz"])
 
     robot_description = ParameterValue(
-        Command(["xacro ", description_file, " ", "ur_type:=", "ur20"]), value_type=str
+        Command(["xacro ", description_file, " ", "ur_type:=", ur_type]), value_type=str
     )
 
     robot_state_publisher_node = Node(
@@ -36,6 +38,30 @@ def generate_launch_description():
         arguments=["-d", rvizconfig_file],
     )
 
+    declared_arguments = [
+        DeclareLaunchArgument(
+            "ur_type",
+            description="Typo/series of used UR robot.",
+            choices=[
+                "ur3",
+                "ur3e",
+                "ur5",
+                "ur5e",
+                "ur10",
+                "ur10e",
+                "ur16e",
+                "ur20",
+                "ur30",
+            ],
+            default_value="ur20",
+        )
+    ]
+
     return LaunchDescription(
-        [joint_state_publisher_gui_node, robot_state_publisher_node, rviz_node]
+        declared_arguments
+        + [
+            joint_state_publisher_gui_node,
+            robot_state_publisher_node,
+            rviz_node,
+        ]
     )