Why fleet geofences produce false alerts
False geofence alerts start with the position behind them. Buildings and trees can shift a position across a boundary, and sparse records can miss a short visit. Test any alert rule against visits you actually observed before relying on it.
Every rule trades one error for another
A position near the edge of a yard can fall on either side once its uncertainty is counted. Requiring two inside fixes removes that false alert but can miss a short real visit. Late-arriving records also need sorting by event time, not arrival time.
Test a rule against real visits
Review steps
- Note the boundary, its purpose and how uncertain fixes are treated.
- Decide what counts as a real visit independently of the rule being tested.
- Compare rules on near-boundary, short, long and missing-record cases.
- Count false alerts and misses separately: a bigger boundary admits neighbors, a smaller one misses visits.
- An alert shows where a vehicle was, not that a delivery was accepted.
Where ReWheel stands
ReWheel FMS connects supported vehicle information with equipment and operational records for field and institutional operations. Vehicle compatibility, data-access requirements, connectivity and installation are assessed per deployment, never assumed. A workflow discussion gives you a written rule-testing plan for your yards.
Geofence event review and rule-validation worksheet
Four cases show uncertainty, missed short visits, late receipts and gaps between fixes. Blank fields support your own review.
On a small screen, scroll this table horizontally. Keyboard users can focus the table region and use arrow keys.
| Case | What really happened | Position records | Any inside fix alerts | Two inside fixes, 2 minutes apart | Tradeoff |
|---|---|---|---|---|---|
| Boundary jitter | Asset stays outside | 10:01 inside by 3 m, uncertainty 8 m; 10:02 outside | Alert: false positive | No alert: correct | A nominal inside point can overlap the boundary |
| Short real visit | Enters 10:03, leaves 10:04 | 10:03 inside; no second inside fix | Alert: correct | No alert: missed visit | Confirmation can miss a short visit |
| Longer visit, late receipts | Inside 10:10 to 10:14 | 10:10 inside, received 10:15; 10:13 inside, received 10:14 | Alert: correct | Alert once both records arrive: correct | Sort by event time, not by arrival |
| Passage between fixes | Inside 10:20 to 10:21 | 10:19 outside; 10:22 outside | No alert: missed visit | No alert: missed visit | Sparse records cannot show a short visit |
Sources and review context
What ReWheel provides
ReWheel FMS connects supported vehicle information with equipment and operational records for field and institutional operations. Vehicle compatibility, data-access requirements, connectivity and installation are assessed per deployment, never assumed.
Continue with ReWheel: How a ReWheel workflow discussion works
Discuss your workflow