Title: "robot_spawn.launch.py fails with generate:=false in Jazzy (regression)"

[Botman-Mike]

Bug Report: robot_spawn.launch.py fails with generate:=false in Jazzy

Issue

The robot does not spawn in Gazebo when using generate:=false parameter in ROS 2 Jazzy, breaking a workflow that worked correctly in Humble.

Environment

• ROS Distribution: Jazzy
• Package: clearpath_gz (clearpath_simulator)
• Branch: jazzy
• File: clearpath_gz/launch/robot_spawn.launch.py
• Line: 208

Expected Behavior

When running:

ros2 launch clearpath_gz simulation.launch.py generate:=false

The robot should spawn in Gazebo without regenerating URDF/SRDF/config files (same behavior as Humble).

Actual Behavior

The robot does not spawn. Only gazebo and parameter_bridge processes start. The spawn action is never added to the launch actions list.

Root Cause

Line 208 in robot_spawn.launch.py:

if not bool(generate.perform(context)):
    actions.append(group_action_spawn_robot)

The Problem: When generate:=false is passed, generate.perform(context) returns the string 'false'. In Python, bool('false') evaluates to True because any non-empty string is truthy. Therefore:

• bool('false') → True
• not bool('false') → False
• The spawn action is never appended

Comparison with Humble (Working Code)

The Humble version correctly uses launch conditions:

do_not_generate = GroupAction(actions=[group_action_spawn_robot],
                              condition=UnlessCondition(LaunchConfiguration('generate')))

UnlessCondition properly handles string-based launch configuration values ('true'/'false').

Fix

Replace lines 208-209:

# BROKEN
if not bool(generate.perform(context)):
    actions.append(group_action_spawn_robot)

With:

# FIX 1: Use proper condition (like Humble)
do_not_generate = GroupAction(actions=[group_action_spawn_robot],
                              condition=UnlessCondition(LaunchConfiguration('generate')))
actions.append(do_not_generate)

# OR FIX 2: Properly check string value
generate_str = generate.perform(context).lower()
if generate_str in ['false', '0', 'no', 'off']:
    actions.append(group_action_spawn_robot)

Impact

This breaks the workflow for users who manually edit robot configuration files in ~/clearpath/ and don't want them overwritten by the generator. The generate:=false parameter is essential for development and customization.

Reproduction Steps

1. Set up a Clearpath robot configuration in ~/clearpath/
2. Run: ros2 launch clearpath_gz simulation.launch.py generate:=false
3. Observe that only Gazebo world loads, no robot spawns
4. Check ros2 node list - only /clock_bridge exists (no robot nodes)

Verified Locations

• GitHub repo (jazzy branch): https://github.com/clearpathrobotics/clearpath_simulator/blob/jazzy/clearpath_gz/launch/robot_spawn.launch.py#L208
• Installed package: /opt/ros/jazzy/share/clearpath_gz/launch/robot_spawn.launch.py:208

Suggested Priority

High - This is a regression from Humble that breaks documented functionality and workflows.