Hi @HaroldMao ,
From the error it looks like there’s an issue with your librealsense package. The best way to address this is by reinstalling it by following these steps:
git clone https://github.com/hello-robot/stretch_install ~/stretch_install
cd ~/stretch_install && git pull
stretch_new_robot_install.sh -u
The -u flag in last command will run a system wide update. This will ensure that there are no conflicting package versions.