[agile quadrotor] add obstacle world spawner and collision detection

[tongtybj]

What is this?

Add obstacle world spawner and collision detection in gazebo

Details

• obstacle world dynamic spawner based on the CSV file with the agile_flight style. Please check https://github.com/tongtybj/aerial_robot/blob/44b3d58b18fd1347ac7d9159a0f8840f779627c9/robots/agile_multirotor/config/obstacle_world/world1.csv
• collsion detection between the obstacles and robot. the obsracle is approximated as cylinder model. Therefore simple euclidian distance is calcualted in https://github.com/tongtybj/aerial_robot/blob/44b3d58b18fd1347ac7d9159a0f8840f779627c9/robots/agile_multirotor/scripts/obstacle_world.py#L69-L78
• add simulated RGBD sensor (e.g., intel realsense D435) to provide depth image for obstacle detection. Please check https://github.com/tongtybj/aerial_robot/blob/44b3d58b18fd1347ac7d9159a0f8840f779627c9/robots/agile_multirotor/urdf/quadrotor.gazebo.xacro#L36-L108

Usage

roslaunch agile_multirotor bringup.launch simulation:=true real_machine:=false headless:=false

Then, you can confirm following status in gazebo and rviz.