Incident Report – Survey Mission Halt at Waypoint 14
Vessel: BlueBoat
Autopilot: CubeOrangePlus
Firmware: ArduRover v4.6.2
Log File: 00000268.log
Location: Reef
Mission Type: Autonomous survey mission
During an autonomous survey mission, the BlueBoat completed transit to waypoint 13 and transitioned normally toward waypoint 14. However, waypoint 14 was never reached. After transitioning to 14, the vessel ceased issuing propulsion commands and began drifting under environmental forces. No critical error, failsafe, or mode change was reported. Manual control was taken briefly, after which Return‑to‑Launch (RTL) executed normally.
The incident appears to involve mission execution logic (MISE) stalling, resulting in propulsion inhibition while navigation and vehicle health remained valid
Timeline of Events
Mission initiated in autonomous survey mode.
Waypoint 13 reached successfully.
Mission advanced automatically from waypoint 13 to waypoint 14.
Shortly after the transition:
Mission execution (MISE logging) stopped.
Thrust commands dropped to zero. NTUN no set to zero distance and bearing
Vessel began drifting.
No error, failsafe, fence alert, or mode change was reported.
Operator took manual control briefly (gentle reverse applied).
RTL was commanded and executed correctly with normal propulsion and navigation.
- Expected Behavior
After reaching waypoint 13, the vehicle should:
Activate guidance toward waypoint 14.
Command forward propulsion.
Continue autonomous navigation until waypoint 14 acceptance criteria are met or a defined abort condition occurs.
If mission progression is blocked, the system is expected to:
Raise a clear user‑visible warning or fault, or
Automatically transition to a safe fallback such as loiter or RTL.
- Observed Behavior
Waypoint 14 was never reached.
Vehicle position remained essentially static after waypoint 13 transition.
No forward propulsion was commanded.
The system remained nominal and responsive.
Manual input immediately restored thrust authority.
RTL completed successfully.
- Log Evidence Summary
5.1 Mission Commands
CMD logs show normal sequencing of MAV_CMD_NAV_WAYPOINT (command 16).
Waypoint index advances cleanly from 13 to 14.
No rejected or failed NAV commands are logged.
5.2 Mission Execution (MISE)
MISE messages stop at the point drift begins.
No subsequent mission state updates are recorded.
This strongly indicates mission execution logic halted or stalled.
5.3 Propulsion
THR logs show:
Throttle output ≈ 0
Desired speed ≈ 0
No evidence of propulsion fault, ESC reset, or power limitation.
5.4 Navigation & Sensors
All remained nominal throughout:
GPS status = 3 (3D fix)
EKF healthy
IMU, compass, depth, and barometer consistent
No position jumps or heading discontinuities
5.5 Power System
Battery voltage stable (~13.4–13.6 V)
Current draw nominal
No undervoltage or power flags
5.6 Safety & Control
No failsafe triggered
No RC override
No mode change
Fence enabled but no explicit fence breach or alert logged at the event time
- Analysis
The vessel did not fail to reach waypoint 14 due to navigation, propulsion, power, or environmental limitations. Instead, the guidance system never commanded motion toward waypoint 14.
The decisive indicators are:
Cessation of MISE logging
Zero propulsion commands despite valid navigation
Immediate recovery with manual control
Successful RTL afterward
This combination is consistent with a mission‑state or autonomy logic stall, where propulsion authority is implicitly inhibited without triggering a fault or automatic recovery behavior.
Based on earlier evidence in the logs (elsewhere in this mission):
MAV command failures (MAV_RESULT_FAILED / CANCELLED) were observed on non‑navigation commands.
Fence logic was enabled with polygon enforcement.
While no explicit fence breach was logged at this waypoint, it is possible that:
A mission‑state transition (end‑of‑line / survey logic) was blocked by a safety or validation layer, or
A failed or cancelled ancillary command caused the mission state machine to abort progression without escalating an error.
- Impact
Autonomous mission halted unexpectedly.
Vessel drifted without warning.
Operator intervention was required.
No loss of vehicle, but operational confidence is impacted.
We request vendor assistance to review and clarify:
MISE stall conditions
Under what circumstances can mission execution halt without:
a fault,
a failsafe,
or an automatic mode transition?
Waypoint transition handling
Are there known conditions where waypoint advancement succeeds but guidance is not activated?
Silent propulsion inhibits
What mechanisms can suppress propulsion output without generating a warning or STATUSTEXT?
Survey / fence interaction
Can fence enforcement or margin logic block mission continuation silently at waypoint or transect transitions?
- Provisional Root Cause (Based on Log Review)
Mission execution logic halted after waypoint 13 due to a mission‑state transition failure or safety arbitration, resulting in propulsion inhibition without a user‑visible fault. Navigation and vehicle systems remained valid, but waypoint 14 guidance was never activated.
Please may you help and advise how to prevent this error in the future, please?