0x000D0018: DROID_GLOBAL_PLANNER_ERROR_A_STAR_GOAL_NOT_TRAVERSABLE
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Applicable alarms (2)
0x000D0018DROID_GLOBAL_PLANNER_ERROR_A_STAR_GOAL_NOT_TRAVERSABLE
Likely outcomes — click to expand
Based on 0 missions where this alarm fired in the last
90 days
(for 0x000D0018) as of 2026-10-13
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This alarm can be caused by a Droid brain with unstable lenses. When that happens, it usually shows up as a poor online calibration history, failed online calibration validators, or poor calibration performance during the leg when the alarm was raised.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
is-this-the-only-issue-or-are-there-oth{"<small><b>Step 1</b></small><br/>Question: Is this the only issue or are there o..."}
check-droid-online-calibration-dashboard["<small><b>Step 2</b></small><br/>Action: Open the Droid Online Calibration Da..."]
check-droid-brain-type{"<small><b>Step 3</b></small><br/>Question: Use the Bad Droid Leaderboard to de..."}
check-brain-swap-date{"<small><b>Step 4</b></small><br/>Question: Use the BRAIN_SWAP_DATE column in t..."}
non-epoxy-brain-with-poor-history{"<small><b>Step 5</b></small><br/>Question: Is the lowest entry in the NON_EPOXY..."}
replace-droid-brain["<small><b>Step 6</b></small><br/>Action: File a work order to replace the Droi..."]
check-online-cal-validation-failures["<small><b>Step 7</b></small><br/>Telemetry: Filter the Validator column for on..."]
online-cal-validator-failed{"<small><b>Step 8</b></small><br/>Question: Did any online_cal validator fail o..."}
check-calibration-performance-on-leg["<small><b>Step 9</b></small><br/>Telemetry: The plot below shows online calibrati..."]
consecutive-bad-segments-nonzero{"<small><b>Step 10</b></small><br/>Question: In the top panel, was consecutive_ba..."}
y-offset-exceeds-stereo-match-ratio{"<small><b>Step 11</b></small><br/>Question: In the second panel, did y_offset_ma..."}
check-alarm-history["<small><b>Step 12</b></small><br/>Action: Open Baraza Missions and Flightsht..."]
check-for-repeat-occurrence{"<small><b>Step 13</b></small><br/>Question: You should see the flight that you ar..."}
escalate-calibration-issue-to-p2-nav{{"<small><b>Step 14</b></small><br/>Escalation: Escalate to P2 Nav On Call. Include w..."}}
escalate-planner-error-to-droid-autonomy{{"<small><b>Step 15</b></small><br/>Escalation: Escalate to P2 Droid Autonomy On Call."}}
follow-the-troubleshooting-guide-for("<small><b>Step 16</b></small><br/>Reference: Follow the troubleshooting guide for ...")
the-aircraft-may-return-to-service("<small><b>Step 17</b></small><br/>Reference: The Aircraft may return to service. C...")
is-this-the-only-issue-or-are-there-oth -->|This is the only issue| check-droid-online-calibration-dashboard
is-this-the-only-issue-or-are-there-oth -->|There are other failures| follow-the-troubleshooting-guide-for
check-droid-online-calibration-dashboard --> check-droid-brain-type
check-droid-brain-type -->|Yes| check-brain-swap-date
check-droid-brain-type -->|No| check-online-cal-validation-failures
check-brain-swap-date -->|Yes| check-online-cal-validation-failures
check-brain-swap-date -->|No| non-epoxy-brain-with-poor-history
non-epoxy-brain-with-poor-history -->|Yes| replace-droid-brain
non-epoxy-brain-with-poor-history -->|No| check-online-cal-validation-failures
non-epoxy-brain-with-poor-history -->|Column is empty| check-online-cal-validation-failures
check-online-cal-validation-failures --> online-cal-validator-failed
online-cal-validator-failed -->|Yes| escalate-calibration-issue-to-p2-nav
online-cal-validator-failed -->|No| check-calibration-performance-on-leg
check-calibration-performance-on-leg --> consecutive-bad-segments-nonzero
consecutive-bad-segments-nonzero -->|Yes| escalate-calibration-issue-to-p2-nav
consecutive-bad-segments-nonzero -->|No| y-offset-exceeds-stereo-match-ratio
y-offset-exceeds-stereo-match-ratio -->|Yes| escalate-calibration-issue-to-p2-nav
y-offset-exceeds-stereo-match-ratio -->|No| check-alarm-history
check-alarm-history --> check-for-repeat-occurrence
check-for-repeat-occurrence -->|Yes| escalate-planner-error-to-droid-autonomy
check-for-repeat-occurrence -->|No| the-aircraft-may-return-to-service
style is-this-the-only-issue-or-are-there-oth fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style check-droid-online-calibration-dashboard fill:#dcfce7,stroke:#22c55e,color:#14532d
style check-droid-brain-type fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style check-brain-swap-date fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style non-epoxy-brain-with-poor-history fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style replace-droid-brain fill:#dcfce7,stroke:#22c55e,color:#14532d
style online-cal-validator-failed fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style consecutive-bad-segments-nonzero fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style y-offset-exceeds-stereo-match-ratio fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style check-alarm-history fill:#dcfce7,stroke:#22c55e,color:#14532d
style check-for-repeat-occurrence fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style escalate-calibration-issue-to-p2-nav fill:#fef3c7,stroke:#f59e0b,color:#78350f
style escalate-planner-error-to-droid-autonomy fill:#fef3c7,stroke:#f59e0b,color:#78350f
style follow-the-troubleshooting-guide-for fill:#f3e8ff,stroke:#a855f7,color:#581c87
style the-aircraft-may-return-to-service fill:#f3e8ff,stroke:#a855f7,color:#581c87 Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Is this the only issue or are there other failures?
2 action
Open the Droid Online Calibration Dashboard.
Set
Set
Start Date to at least 1 month before the incident date. Set End Date to after the incident date. In the ASSET_ID dropdown, uncheck Select All, search for the relevant Droid ID, then select that Droid. 3 question
Use the
Bad Droid Leaderboard to determine the brain type during the incident. Are there entries for this droid in the NON_EPOXY_PERFORMANCE column? 4 question
Use the
BRAIN_SWAP_DATE column in the Bad Droid Leaderboard to determine the brain type during the incident. (No entry means no swap.) Is there a date entry in the BRAIN_SWAP_DATE column that pre-dates this incident? 5 question
Is the lowest entry in the
NON_EPOXY_PERFORMANCE column below 0.4? 6 action
File a work order to replace the Droid brain using this template.
7 telemetry
Filter the
Validator column for online_cal, then filter the Result column for Pass and Fail. There should be at least 7 calibration checks. Enter the mission identifier above to load failed maintenance validator results.
8 question
Did any
online_cal validator fail on this flight? 9 telemetry
The plot below shows online calibration map failure diagnostics over the mission. Scrub the time slider to the mission leg when the alarm was raised.
Enter the mission identifier above to load the plot.
10 question
In the top panel, was
consecutive_bad_segments non-zero during the current leg? 11 question
In the second panel, did
y_offset_mad_px exceed stereo_match_ratio during the flight? 12 action
Open Baraza Missions and Flights.
Clear all filters by clicking on the button on the top left. It will pop open a dialog called
In the top middle of the page, there are three date-related boxes. The left-most one has convenient presets, the middle one is start date, and the right one is end date. Click on the left box and select "Past Week".
On the left side of the page, click on
Enter the Droid ID under
Enter "DROID_GLOBAL_PLANNER_ERROR_A_STAR_GOAL_NOT_TRAVERSABLE" under
Click the
If it takes more than 5 minutes to return or returns
Clear all filters by clicking on the button on the top left. It will pop open a dialog called
Applied Filters. If it is not empty, clear the checkmark on Unselect All, which will uncheck all checkboxes, and the click the Apply button.In the top middle of the page, there are three date-related boxes. The left-most one has convenient presets, the middle one is start date, and the right one is end date. Click on the left box and select "Past Week".
On the left side of the page, click on
Filters.Enter the Droid ID under
Assets.Enter "DROID_GLOBAL_PLANNER_ERROR_A_STAR_GOAL_NOT_TRAVERSABLE" under
Failure Reason.Click the
Apply button.If it takes more than 5 minutes to return or returns
Err, then Baraza is having problems and you should try again in 15 minutes. 13 question
You should see the flight that you are trying to triage. Have there been any other times that this alarm has been raised for this Droid in the past week?
15 escalation
Escalate to P2 Droid Autonomy On Call.
16 reference
Follow the troubleshooting guide for the other failures.
17 reference
The Aircraft may return to service. Calibration was not identified as a contributor.
Resolution note
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