Boat Setup and Configuration

Tuning Rover firmware is a matter of order, not of piling up parameters: get power and signals right, calibrate the sensors and set up positioning and power, confirm every output moves correctly, and only then touch the tuning values. Get the order wrong and you end up tuning around a wiring fault.

Setup order

Step	What to do	Where
0	Flash Rover firmware and confirm the vehicle is recognised as a boat	Flashing boat firmware
1	Power the controller, GNSS, radio and BEC, and mount the controller at the standard orientation	Mounting the controller and accessories
2	Wire the steering servo and propulsion ESCs for the hull; twin screw uses both sides	Thruster and servo connections
3	On a boat with sails, enable sailboat mode and calibrate sail travel	Sailboat mode
4	Enter the basics: FRAME_CLASS, GPS_NAVFILTER and the throttle and steering items	Key parameters on this page
5	Calibrate accelerometer and compass, and set up positioning and the power module	Three calibration sections below
6	Remove the propeller and run the motor test, confirming each output, rudder direction and thrust direction	Pre-flight check below

Key parameters

Parameter	Value	Notes
FRAME_CLASS	2	Boat; 1 is ground vehicle, 3 is balance bot
SERVO1_FUNCTION / SERVO3_FUNCTION	26 / 70	Steering servo and throttle; change to 73 / 74 for a twin-screw boat
MOT_PWM_TYPE	0	0 is normal PWM; OneShot and DShot150~1200 are also available
MOT_SPD_SCA_BASE	0	Above this speed the steering angle is scaled down to limit heel; 0 disables
MOT_VEC_ANGLEMAX	0	Servo travel from centre to full deflection with vector thrust, 0~90°; 0 disables
CRUISE_SPEED / CRUISE_THROTTLE	Per boat	Cruise speed and base throttle for auto modes
TURN_RADIUS	Per boat	Turning radius at low speed; directly affects how well the boat tracks a route
ATC_STR_RAT_FF	Per boat	Steering feed-forward; tune this first when the boat drifts off a straight line
GPS_NAVFILTER	5	5 is Sea, filtered with a sea-level model; not for high-altitude water
LOIT_TYPE / LOIT_RADIUS	0 / Per boat	0 heads for the target forwards or backwards, 1 bow first, 2 stern first; radius 0~20 m

Accelerometer and compass calibration

For accelerometer and compass calibration, follow the Sensor calibration page.

GPS and RTK configuration

For GPS and RTK module configuration, follow the GPS and RTK positioning module page.

Power module configuration

For power module configuration and calibration, follow the Power monitor page.

Pre-flight check

1. Press the safety switch and arm; outputs only carry signal after that. If neither rudder nor motor moves, check this step first rather than changing parameters.
2. Open the motor test in the ground station and step through outputs 1~4, confirming each number matches the physical ESC and wiring.
3. Remove the propeller, switch to manual mode and raise throttle slowly to confirm the ESC spins the right way; both sides must match on a twin-screw boat.
4. Steer and confirm rudder direction. If it is reversed, check SERVOx_REVERSED first, then whether the channels are swapped.
5. Radio channels and output channels are two different things: radio channels are mapped in RCMAP_*, output channels are set by SERVOx_FUNCTION. Adjust them separately.

Common symptoms

Symptom	Cause	Fix
Steering servo does not move	SERVO1_FUNCTION still 0	Set to 26
ESC beeps but does not turn	Not armed, or the safety switch is not pressed	Press the safety switch and arm
Twin-screw boat spins in place	Left and right ESCs swapped	Swap 73 / 74
Boat reverses when commanded forward	ESC direction or SERVO3_REVERSED	Fix the parameter first, then swap the wiring
Weaves along a straight line	Compass picking up power-lead noise, or GPS_NAVFILTER not set to 5	Separate the leads, recalibrate the compass, then set the Sea filter
Drifts after reaching a waypoint	Not in Loiter, or LOIT_RADIUS too large	Check the mode and the radius

Parameters only fix parameter problems

A reversed output in the motor test can be made to look right either by changing a parameter or by swapping wires, but swapping wires is the real fix. Keep parameters for travel, dead zone and PID — the places that genuinely need numbers.