When an AGV moves through a warehouse, it encounters multiple access points (APs) along its route. If the AGV doesn’t switch to the strongest AP quickly, it may:
“Stick” to a weak signal
Experience dropped packets
Temporarily stop if safety thresholds are triggered
Key metric: Handover Time – the delay for the AGV to switch from one AP to the next.
Example: Enterprise Cisco APs with 802.11r/k/v fast roaming can achieve <50 ms handover. AGVs generally need <100 ms to avoid triggering emergency stop logic.
| Standard | Purpose |
|---|---|
| 802.11r | Fast BSS Transition (FT) – quick authentication with a new AP without full WPA2 handshake |
| 802.11k | Radio Resource Management – AGV knows candidate APs in advance |
| 802.11v | Network-assisted roaming – AP can steer AGV proactively |
Tip: Verify that the AGV Wi-Fi module and firmware fully support 802.11r/k/v with your supplier.
Option A: Fat AP (Standalone)
Pros: Simple, lower infrastructure cost
Cons: Roaming depends on client logic; handover may be slower
Option B: Controller-Based (Centralized)
Pros: Controller coordinates roaming, faster handoff, optimized channels
Cons: Higher cost, slightly more complex to maintain
Best practice: Large warehouses with moving AGVs usually use controller-based architecture.
AP Placement & Overlap: 15–20% overlap; AGV paths should always be within 1–2 strong AP signals
Signal Threshold Settings: Set minimum RSSI (e.g., -65 dBm) to prevent sticking
Bandwidth & Channel Planning: Non-overlapping channels, prefer 5 GHz band
Load Balancing: Ensure multiple AGVs don’t saturate a single AP
Test Real Paths: Walk routes with Wi-Fi analyzer; log handover events and latency; adjust transmit power as needed
Use SNMP or controller logs to monitor roaming events
RCS systems often log AGV connectivity drops
Create Wi-Fi signal heatmaps of the warehouse
Conduct dry-run AGV missions to validate handovers
Fast roaming support (802.11r/k/v) is critical for uninterrupted AGV operation
Controller-based Wi-Fi generally outperforms standalone APs for fleets
Tune handover thresholds and signal overlaps per aisle and blind turn
Continuous RSSI and latency monitoring prevents “sticking” and safety stops
Coordination between IT, AGV supplier, and warehouse ops is essential
AP placement map
Signal threshold values
Roaming test plan
Handover latency logging template
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