simulation/docs/usage.md

Usage Guide

How to run and control the simulation.

Starting the Simulation

cd ~/simulation
source activate_venv.sh
bash scripts/run_simulation.sh

This launches:

1. Gazebo with the drone model
2. ArduPilot SITL (flight controller)
3. MAVProxy console (for commands)

Simulation Options

# Default (iris_runway world)
bash scripts/run_simulation.sh

# Specific world
bash scripts/run_simulation.sh --world iris_runway

# Rover instead of copter
bash scripts/run_simulation.sh --vehicle Rover

# Software rendering (for WSL or no GPU)
bash scripts/run_simulation.sh --software-render

# Show available options
bash scripts/run_simulation.sh --help

Controlling the UAV

MAVProxy Console

The simulation opens a MAVProxy console. Commands:

mode guided      # Switch to GUIDED mode (required for commands)
arm throttle     # Arm motors
takeoff 5        # Takeoff to 5 meters altitude

# Fly to position (North, East, Down in meters)
guided 10 0 -5   # 10m north, 0m east, 5m altitude
guided 10 10 -5  # 10m north, 10m east, 5m altitude
guided 0 0 -5    # Return to origin at 5m altitude

rtl              # Return to launch
land             # Land at current position
disarm           # Disarm motors (after landing)

ROS 2 Interface

If MAVROS is running, control via ROS 2:

# Arm
ros2 service call /mavros/cmd/arming mavros_msgs/srv/CommandBool "{value: true}"

# Set GUIDED mode
ros2 service call /mavros/set_mode mavros_msgs/srv/SetMode "{custom_mode: 'GUIDED'}"

# Takeoff
ros2 service call /mavros/cmd/takeoff mavros_msgs/srv/CommandTOL "{altitude: 5}"

# Fly to position (local frame, meters)
ros2 topic pub /mavros/setpoint_position/local geometry_msgs/PoseStamped \
  "{header: {frame_id: 'map'}, pose: {position: {x: 10, y: 5, z: 5}}}"

# Land
ros2 service call /mavros/cmd/land mavros_msgs/srv/CommandTOL "{}"

Monitoring

# List topics
ros2 topic list

# View position
ros2 topic echo /mavros/local_position/pose

# View velocity
ros2 topic echo /mavros/local_position/velocity_local

# View IMU
ros2 topic echo /mavros/imu/data

Flight Modes

Mode	Description
STABILIZE	Manual control with attitude stabilization
ALT_HOLD	Maintain altitude, manual position
LOITER	Hold position and altitude
GUIDED	Accept position commands
AUTO	Follow pre-planned mission
RTL	Return to launch point
LAND	Controlled descent and landing

Stopping the Simulation

Press Ctrl+C in the terminal running the simulation.

Or run:

bash scripts/kill_simulation.sh

Camera Topics

The UAV has two cameras:

# Forward camera (visual odometry)
ros2 topic echo /uav/camera/forward/image_raw

# Downward camera (optical flow)
ros2 topic echo /uav/camera/downward/image_raw

GPS-Denied Navigation

All position commands use local coordinates (meters from takeoff point):

• X: North
• Y: East
• Z: Up (or Down for NED frame)

GPS is only used for geofencing boundaries, not for navigation.