Unable to build ORB_SLAM3 with ROS using ./build_ros.sh on ubuntu 20.04 with ros-noetic-desktop-full

TL;DR

Issue UZ-SLAMLab/ORBSLAM3#913 (closed, 9 comments): I have installed ros-noetic-desktop-full Paths for rosroot and rospackage are echo $ROSROOT /opt/ros/noetic/share/ros echo $ROSPACKAGEPATH /opt/ros/noetic/share:~/ORBSLAM3/Examplesold/ROS/ORBSLAM3 after running./buildros.sh, I get [rosbuild] Building package ORBSLAM3 Failed to invoke /opt/ros/noetic/bin/rospack deps-manifests ORBSLAM3 ModuleNotFoundError: No module named 'rosdep2' [rospack] Error: could not find python module 'rosdep2.rospack'. is rosdep up-to-date (at least 0.10.4)?

Steps

1. Issue UZ-SLAMLab/ORBSLAM3#913 (closed, 9 comments): I have installed ros-noetic-desktop-full Paths for rosroot and rospackage are echo $ROSROOT /opt/ros/noetic/share/ros echo $ROSPACKAGEPATH /opt/ros/noetic/share:~/ORBSLAM3/Examplesold/ROS/ORBSLAM3 after running ./buildros.sh, I get [rosbuild] Building package ORBSLAM3 Failed to invoke /opt/ros/noetic/bin/rospack deps-manifests ORBSLAM3 ModuleNotFoundError: No module named 'rosdep2' [rospack] Error: could not find python module 'rosdep2.rospack'. is rosdep up-to-date (at least 0.10.4)? CMake Error at /opt/ros/noetic/share/ros/core/rosbuild/public.
2. The ORBSLAM3 ROS build failing with 'No module named rosdep2' (and rospack errors) was fixed by the reporter with a clean reinstall: purge ros-noetic from the system and reinstall it using the standard ROS Noetic Ubuntu install instructions. The broken install was the problem, not the ORBSLAM3 build itself.

When to use

You are seeing this: CMake Error at /opt/ros/noetic/share/ros/core/rosbuild/public. Use this skill when you run into "Unable to build ORBSLAM3 with ROS using ./buildros.sh on ubuntu 20.04 with ros-noetic-desktop-full".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

Versions mentioned in the source: least 0.10.4. If you are on something much newer or older, the details may have shifted.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Sources

• https://github.com/UZ-SLAMLab/ORB_SLAM3/issues/913

In gh:UZ-SLAMLab/ORBSLAM3#913, the reporter ran into: Issue UZ-SLAMLab/ORBSLAM3#913 (closed, 9 comments): I have installed ros-noetic-desktop-full Paths for rosroot and rospackage are echo $ROSROOT /opt/ros/noetic/share/ros echo $ROSPACKAGEPATH /opt/ros/noetic/share:~/ORBSLAM3/Examplesold/ROS/ORBSLAM3 after running ./buildros.sh, I get [rosbuild] Building package ORBSLAM3 Failed to invoke /opt/ros/noetic/bin/rospack deps-manifests ORBSLAM3 ModuleNotFoundError: No module named 'rosdep2' [rospack] Error: could not find python module 'rosdep2.rospack'. is rosdep up-to-date (at least 0.10.4)? CMake Error at... The verified answer was: The ORBSLAM3 ROS build failing with 'No module named rosdep2' (and rospack errors) was fixed by the reporter with a clean reinstall: purge ros-noetic from the system and reinstall it using the standard ROS Noetic Ubuntu install instructions. The broken install was the problem, not the ORBSLAM3 build itself. Source issue: https://github.com/UZ-SLAMLab/ORBSLAM3/issues/913