엔지니어스 - Engineeus

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://packages.ros.org/ros/ubuntu xenial InRelease: The following signatures were invalid: KEYEXPIRED 1622248854 W: Failed to fetch http://packages.ros.org/ros/ubuntu/dists/xenial/InRelease The following signatures were invalid: KEYEXPIRED 1622248854 W: Som..