# Flight controller settings for the DD24-B Duckiedrone (PX4).
#
# This file holds all the settings the drone's flight controller needs in order
# to fly: what shape the frame is, where the motors are and which way they spin,
# which sensors are fitted, and how the drone should behave. Loading it all at
# once saves you from typing in dozens of settings by hand.
#
# How to use it: open QGroundControl, connect the flight controller over USB,
# then go to Vehicle Setup > Parameters > Tools > Load from file, choose this
# file, and reboot the flight controller when it asks.
#
# One thing you still do yourself afterwards: calibrate the sensors
# (accelerometer, gyroscope and level horizon) in QGroundControl. Those readings
# are different for every board, so they are not saved in here.
#
# Each setting below has a short note above it explaining what it does. You do
# not need to understand every line to use the file; the notes are just there
# if you are curious. A few of them link to the PX4 documentation if you want to
# read more.
#
# Vehicle-Id Component-Id Name Value Type
#
# --- Airframe name ---
# SYS_AUTOSTART picks a ready-made "recipe" for the airframe (4001 = a generic
# quad in X layout). On a normal PX4 that recipe would set up the whole frame
# for you. This stripped-down build does not run the recipe, so the number does
# nothing here except show a friendly name in QGroundControl. The real frame is
# built by hand in the CA_ block just below.
1	1	SYS_AUTOSTART	4001	6
# --- Frame shape and motor layout ---
# Tells everyone "I am a quadcopter" (2 = quad). QGC and MAVROS read this to
# draw the right icon and pick sensible defaults.
1	1	MAV_TYPE	2	6
# The kind of vehicle for the motor-mixing math. 0 = multirotor.
1	1	CA_AIRFRAME	0	6
# How many motors we have. Four.
1	1	CA_ROTOR_COUNT	4	6
# The next block tells PX4 exactly where each motor sits and which way it spins,
# so it can work out how to mix them for roll, pitch and yaw. Positions are
# normalized: PX is front (+) / back (-), PY is right (+) / left (-). KM is the
# spin direction: a plus sign means the propeller turns counter-clockwise, a
# minus sign means clockwise. This pattern is "props-in".
# More on control allocation: https://docs.px4.io/v1.15/en/config/actuators.html
# Motor 1: front-right corner, spins counter-clockwise.
1	1	CA_ROTOR0_PX	1.0	9
1	1	CA_ROTOR0_PY	1.0	9
1	1	CA_ROTOR0_KM	0.05	9
# Motor 2: rear-left corner, spins counter-clockwise.
1	1	CA_ROTOR1_PX	-1.0	9
1	1	CA_ROTOR1_PY	-1.0	9
1	1	CA_ROTOR1_KM	0.05	9
# Motor 3: front-left corner, spins clockwise.
1	1	CA_ROTOR2_PX	1.0	9
1	1	CA_ROTOR2_PY	-1.0	9
1	1	CA_ROTOR2_KM	-0.05	9
# Motor 4: rear-right corner, spins clockwise.
1	1	CA_ROTOR3_PX	-1.0	9
1	1	CA_ROTOR3_PY	1.0	9
1	1	CA_ROTOR3_KM	-0.05	9
# --- Motor outputs ---
# Which motor each output pin drives. Output 1 goes to Motor 1, output 2 to
# Motor 2, and so on (101..104 are PX4's codes for "Motor 1".."Motor 4").
1	1	PWM_MAIN_FUNC1	101	6
1	1	PWM_MAIN_FUNC2	102	6
1	1	PWM_MAIN_FUNC3	103	6
1	1	PWM_MAIN_FUNC4	104	6
# The language the flight controller speaks to the ESCs. -3 means DShot600, a
# fast digital protocol (not the old analog PWM). Both motor timer groups use it.
1	1	PWM_MAIN_TIM0	-3	6
1	1	PWM_MAIN_TIM1	-3	6
# --- Which sensors are fitted ---
# These tell PX4 which sensors are really on the board. This drone has no
# barometer, no compass (magnetometer) and no GPS, so all three are 0.
1	1	SYS_HAS_BARO	0	6
1	1	SYS_HAS_MAG	0	6
1	1	SYS_HAS_GPS	0	6
# --- Position and height estimation ---
# EKF2 is the math that estimates where the drone is and how high it is by
# blending the sensors together. Since the only things we have are the IMU and
# a downward range sensor (ToF), we switch off every source we do not have and
# tell it to trust the range sensor for height.
# Full list: https://docs.px4.io/v1.15/en/advanced_config/parameter_reference.html
# Keep this on even without a barometer. PX4 won't read one if absent, but
# turning it off stops height estimation entirely.
1	1	EKF2_BARO_CTRL	1	6
# Do not use GPS.
1	1	EKF2_GPS_CTRL	0	6
# Do not use external vision or a motion-capture system.
1	1	EKF2_EV_CTRL	0	6
# Do not use an optical-flow camera.
1	1	EKF2_OF_CTRL	0	6
# Do not use a compass at all (5 = none), so the estimator never tries to.
1	1	EKF2_MAG_TYPE	5	6
# Use our bottom facing ToF Sensor for Height estimate
1	1	EKF2_HGT_REF	2	6
# Use the downward rangefinder in EKF2.
# 0=off, 1=Enabled (Conditional), 2=Enabled (Always)
1	1	EKF2_RNG_CTRL	2	6
# The closest distance (in meters) a range reading is trusted from.
1	1	EKF2_MIN_RNG	0.01	9
# --- Motion sensor (IMU) ---
# The IMU has accelerometers and gyroscopes. 
# The next three lines tune how its signal is sampled and smoothed.
# Smooth the gyro's rate-of-change signal by trimming noise above 20 Hz.
1	1	IMU_DGYRO_CUTOFF	20.0	9
# How many gyro samples per second are handed to the controller (800 per second).
1	1	IMU_GYRO_RATEMAX	800	6
# How often (times per second) IMU readings are bundled up for the estimator.
1	1	IMU_INTEG_RATE	250	6
# --- Safety, battery and communication ---
# A "circuit breaker" that switches off the power-supply sanity check. 894281 is
# the specific unlock number PX4 expects.
1	1	CBRK_SUPPLY_CHK	894281	6
# How many cells the flight battery has. Ours is a 4-cell (4S) pack.
1	1	BAT1_N_CELLS	4	6
# What to do when the battery runs low. 3 = land.
1	1	COM_LOW_BAT_ACT	3	6
# What the drone does if it loses the data link to the companion computer (the
# Pi running MAVROS). 0 = disabled (no action). We disable this check since the
# drone has no GPS, so a real return home cannot happen anyway.
# Ref: https://docs.px4.io/v1.15/en/advanced_config/parameter_reference.html#NAV_DLL_ACT
1	1	NAV_DLL_ACT	0	6
# By default PX4 also treats a lost radio-control link as an emergency.
# This lets some modes carry on without one. 4 = allow it in OFFBOARD, so the
# companion computer can drive the drone with no RC transmitter plugged in.
# Ref: https://docs.px4.io/v1.15/en/advanced_config/parameter_reference.html#COM_RCL_EXCEPT
1	1	COM_RCL_EXCEPT	4	6
# Which version of the MAVLink messaging language to speak. 2 = MAVLink 2, the
# modern one that MAVROS and QGroundControl expect.
1	1	MAV_PROTO_VER	2	6