Question about assigning unique Solid names in a PROTO file

[JoelRamosBeltran]

Hello,

Is it possible to change the name of a Solid by modifying the name field of the robot?

I have the following robot PROTO:

#VRML_SIM R2023b utf8
# license: Apache License 2.0
# license url: http://www.apache.org/licenses/LICENSE-2.0
# This is a proto file for Webots for the rbrobout
# template language: javascript
# Extracted from: /home/joel/Documentos/GitHub/Robotnik_practicas/Robotnik_ws/src/robot_description/robots/rbrobout/rbrobout.urdf


PROTO rbrobout [
  field  SFVec3f     translation     0 0 -0.49
  field  SFRotation  rotation        0 0 1 0
  field  SFString    name            "rbrobout"  # Is `Robot.name`.
  field  SFString    controller      "<extern>"      # Is `Robot.controller`.
  field  MFString    controllerArgs  []          # Is `Robot.controllerArgs`.
  field  SFString    customData      ""          # Is `Robot.customData`.
  field  SFBool      supervisor      FALSE       # Is `Robot.supervisor`.
  field  SFBool      synchronization TRUE        # Is `Robot.synchronization`.
  field  SFBool      selfCollision   FALSE       # Is `Robot.selfCollision`.
  field  MFNode      toolSlot        []          # Extend the robot with new nodes at the end of the arm.
]
{
  Robot {
  translation IS translation
  controller IS controller
  physics Physics {
          }
  children [
    Shape {
      appearance PBRAppearance {
        baseColor 0.5 0.5 0.5
        roughness 1
        metalness 0
      }
      geometry Box {
        size 0.001 0.001 0.001
      }
    }
    Solid {........

And, in that PROTO, i have this field:

Solid {
          translation -0.8 -0.3666 -0.06
          rotation 0 0 -1 2.356194
          children [
            USE microscan3_visual
            Solid {
              translation 0 0 0.11
              children [
                Lidar {
                  name "robot_rear_laser_sensor"
                  horizontalResolution 700
                  fieldOfView 4.7
                  numberOfLayers 1
                  minRange 0.05
                  maxRange 64
                  noise 0.000156
                  resolution 0.00575
                }
              ]
              name %<= fields.name.value + "/rear_laser_link" >%
            }
          ]
          name %<= fields.name.value + "/rear_laser_base_link" >%
          boundingObject USE microscan3
          physics Physics {
            density -1
            mass 1.15
            centerOfMass [
              0 0 0.075
            ]
            inertiaMatrix [
              0.003337012 0.003358383 0.002382896
              0 0 0
            ]
          }
        }
      ]

Then, I'm trying to spawn the PROTO using this service call in a Python launcher:

spawn_robot_service_call = ExecuteProcess(
    cmd=[
        'ros2', 'service', 'call', 
        '/Ros2Supervisor/spawn_node_from_string', 
        'webots_ros2_msgs/srv/SpawnNodeFromString', 
        [
            TextSubstitution(text='{data: "'), 
            robot, TextSubstitution(text=' { name \\"'), 
            namespace, TextSubstitution(text='\\" translation '), 
            x_pos, TextSubstitution(text=' '), 
            y_pos, TextSubstitution(text=' '), 
            z_pos, TextSubstitution(text=' }"}')
        ]
    ],
    output='screen'
    )
    ld.add_action(spawn_robot_service_call)

However, Webots logs this error:

:576:20: error: Expected string literal, found 'rbrobout/rear_laser_link'.

I'm not sure if I wrote the name assignment incorrectly, or if it's just not possible to dynamically assign unique Solid names using string concatenation like this.

I need to do this because I want to spawn multiple instances of the same PROTO robot in the simulation, each with a different name.

The TFs are being published by the WebotsController with 'set_robot_state_publisher':

    rbrobout_driver = WebotsController(
        robot_name='rbrobout',
        namespace='rbrobout',
        parameters=[
            {'robot_description': robot_controller_path,
             'use_sim_time': use_sim_time,
             'set_robot_state_publisher': True,
             'update_rate': 100},
             ros2_control_params
        ],
        respawn=True
    )
    ld.add_action(rbrobout_driver)

[ShuffleWire]

you need the quote around the name, hence instead of
name %<= fields.name.value + "/rear_laser_link" >%
use
name "%<= fields.name.value + "/rear_laser_link" >%"

[JoelRamosBeltran]

It not works for me.

Using:
name "%<= fields.name.value + "/rear_laser_link" >%"

Webots log is:

And using:
name "%<= fields.name.value + '/rear_laser_link' >%"

The solid name changes to:
[robot_state_publisher-1] [INFO] [1744184856.716300466] [rbrobout.robot_state_publisher]: got segment %<= fields.name.value + '/rear_laser_link' >%