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