About Collision Avoidance package

I’m new to developing software, I have trouble in using Collision Avoidance package.

After install package, I want to run local_planner_stereo.launch file. so I types ‘roslaunch local_planner local_planner_stereo.launch’ command in terminal, simulation was executed.

So I put the command ‘rosrun mavros mavsys mode -c OFFBOARD’, but the error occurred. The error message was ‘MODE : Unsupported FCU’. What I have to do for solve this problem?
I needs help…