Cube Orange+ Rover (Twin Motor Boat) - Flycolor 120A ESC Initialization & Dangerous Behavior

Your Builds Boats
1

Hi everyone,

​I am working on a twin-motor USV (Unmanned Surface Vehicle) project. I am relatively new to ArduPilot systems, so I might be missing some basic configuration steps. I am facing a dangerous initialization issue with my ESCs.

​Hardware Setup:

  • ​FC: Cube Orange+ (Standard Carrier Board, ADSB version).

  • ​Firmware: ArduRover 4.6.3 (Stable).

  • ​ESCs: 2x Flycolor 120A Brushless ESC (Boat/Car version with Reverse).

  • ​RC: RadioLink AT9S Pro Transmitter & R9DS Receiver (SBUS connected to RCIN).

  • ​Power: 4S LiPo.

​The Issue:

When I power up the system with default settings (Trims at 1500), the two motors behave completely differently:

  1. ​Left Motor: Keeps beeping continuously (indicating throttle signal is not detected or not at neutral).

  2. ​Right Motor: Beeps once and then immediately spins up to FULL THROTTLE (even though the transmitter stick is at neutral!).

​Critical Observation:

When I try to change the SERVO_TRIM values to something else (e.g., 1000 or 1100) to stop the full-throttle behavior, both motors stop working completely and just beep continuously. I cannot get any response.

​Current Configuration:

  • ​FRAME_CLASS: 2 (Boat)

  • ​FRAME_TYPE: 0 (Undefined/Default)

  • ​SERVO1_FUNCTION: 73 (Throttle Left)

  • ​SERVO3_FUNCTION: 74 (Throttle Right)

  • ​SERVO1_TRIM / SERVO3_TRIM: 1500 (Currently set to Center)

  • ​SERVO1_MIN / SERVO3_MIN: 1100

  • ​SERVO1_MAX / SERVO3_MAX: 1900

  • ​MOT_PWM_TYPE: 0 (Normal PWM)

  • ​BRD_SAFETY_MASK: 16383 (Safety switch bypassed).

  • ​ARMING_REQUIRE: 0 (Disabled to force signal output).

​What I have tried so far:

  1. ​Channel Mapping: I suspected there might be a mismatch between my transmitter’s throttle channel and the Cube’s throttle channel input. I attempted to adjust the mapping to fix this, but it did not resolve the issue. The strange behavior persists.

  2. ​Direct Receiver Test: When I connect the ESCs directly to the Receiver (Channel 3), they calibrate successfully and work perfectly as intended. However, when I connect them back to the Cube, they do not work as I want (either beeping or full throttle) and I cannot replicate that smooth operation.

​My Question:

Why would one motor refuse to arm while the other goes full throttle? And why does changing trims cause them to lose signal completely? It seems like a PWM range or Calibration mismatch between the Cube and the Flycolor ESCs.

​Any help is appreciated.

​Thanks.

2

Set LOG_DISARMED,1 and run through the dangerous/faulty startup process.
Download the .bin log file that is generated and upload it to your favourite file sharing service and provide a link here.
Remember to set LOG_DISARMED,0 afterwards.

3

Thanks to your help, I have resolved the GPS and Compass issues. The system is now showing “Ready to Fly” and I can ARM the vehicle successfully.

​However, the original issue I described in my first post is still persisting:

Even though the vehicle ARMs now, the motors still beep rapidly as soon as I connect them. It seems like the Cube is sending a “Full Throttle” signal immediately upon connection.

​I still get absolutely no response from the RC Transmitter sticks. Moving the throttle or steering stick does not stop the beeping or spin the motors.

​Do you have any advice on which parameters I should check to fix this output signal issue?

Screenshot_20260131_142407_Gallery
Screenshot_20260131_142407_Gallery1080×2340 382 KB

4

The LOG_DISARMED .bin log gives everything we might need to know, including parameters.
I cant think of any specifics right now, but seeing everything together may give us clues.