RDC_Simulation/docs/drone_guide.md

Drone Controller Guide

Overview

The DroneController class (src/drone_controller.py) provides a simple interface for controlling the drone in ArduPilot SITL simulation.

Command Line Usage

# Activate environment first
cd ~/RDC_Simulation
source activate.sh

# Run flight patterns
python scripts/run_ardupilot.py --pattern square
python scripts/run_ardupilot.py --pattern circle
python scripts/run_ardupilot.py --pattern hover

Options

Option	Default	Description
--pattern, -p	square	Flight pattern: square, circle, hover
--altitude, -a	5.0	Flight altitude in meters
--size, -s	5.0	Pattern size (side length or radius)
--connection, -c	tcp:127.0.0.1:5760	MAVLink connection string
--gps	false	Use GPS mode (default is GPS-denied)

Examples

# Large square at high altitude
python scripts/run_ardupilot.py --pattern square --size 10 --altitude 15

# Small circle
python scripts/run_ardupilot.py --pattern circle --size 3 --altitude 5

# Hover for testing
python scripts/run_ardupilot.py --pattern hover

# GPS mode (instead of GPS-denied)
python scripts/run_ardupilot.py --pattern square --gps

Python API

Basic Usage

from src.drone_controller import DroneController

# Create and connect
drone = DroneController()
if not drone.connect():
    print("Connection failed")
    exit(1)

# Setup for GPS-denied (disables arming checks)
drone.setup_gps_denied()

# Set mode and arm
drone.set_mode("GUIDED_NOGPS")  # or "GUIDED" for GPS mode
drone.arm()

# Takeoff
drone.takeoff(5.0)

# Fly a pattern
drone.fly_square(size=5, altitude=5)

# Land
drone.land()

DroneController Class

Constructor

drone = DroneController(connection_string="tcp:127.0.0.1:5760")

Properties

Property	Type	Description
armed	bool	Is the drone armed?
mode	str	Current flight mode
altitude	float	Current altitude (meters)
position	dict	Current position {"x", "y", "z"}
vehicle_type	str	"copter" or "plane"

Methods

Method	Description
connect(timeout=30)	Connect to SITL, returns True/False
set_mode(mode)	Set flight mode (GUIDED, GUIDED_NOGPS, LAND, etc.)
setup_gps_denied()	Configure for GPS-denied operation
arm()	Arm motors (force arm)
takeoff(altitude)	Take off to altitude
goto(x, y, z)	Go to position (NED frame)
fly_to_and_wait(x, y, alt)	Go to position and wait until reached
fly_square(size, alt)	Fly square pattern
fly_circle(radius, alt)	Fly circle pattern
land()	Land the drone
set_param(name, value)	Set an ArduPilot parameter

Flight Modes (ArduCopter)

Mode	ID	Description
STABILIZE	0	Manual control, self-leveling
ALT_HOLD	2	Hold altitude, manual position
GUIDED	4	Accept waypoint commands (needs GPS)
LOITER	5	Hold position
RTL	6	Return to launch
LAND	9	Automatic landing
GUIDED_NOGPS	20	Accept commands without GPS

Coordinate System

ArduPilot uses NED (North-East-Down):

• X (North): Positive = forward
• Y (East): Positive = right
• Z (Down): Positive = down, negative = up!

# Go 5m forward, 3m right, at 10m altitude
drone.goto(5, 3, -10)  # Z is negative for altitude!

GPS-Denied Mode

The controller defaults to GPS-denied mode, which:

1. Disables arming checks (ARMING_CHECK=0)
2. Uses GUIDED_NOGPS mode (ID 20)
3. Relies on barometer for altitude

To use GPS mode instead:

python scripts/run_ardupilot.py --pattern square --gps

Troubleshooting

Drone won't arm

1. Check MAVProxy console for pre-arm errors
2. Try force arming in MAVProxy: arm throttle force
3. Make sure SITL is connected to Gazebo (shows "JSON received:")

Mode not changing

Check the current mode in MAVProxy console. If stuck, try:

mode GUIDED

Drone not moving

1. Make sure you're in GUIDED or GUIDED_NOGPS mode
2. Check altitude - drone needs to be off ground
3. Verify Gazebo is running and responsive

Wrong vehicle type detected

If you see ArduPlane modes (FBWA, FBWB), restart SITL:

pkill -9 -f sim_vehicle
sim_vehicle.py -v ArduCopter -f gazebo-iris --model JSON --console --wipe-eeprom