Consus: BLE Tracker & AoA

A client was developing Consus, a tool-tracking system for manufacturing floors. The familiar shop problem: where is each calibrated tool, fixture, and instrument, right now, across hundreds of workstations? Barcode and scan-at-handoff workflows lose tools anyway. The Consus approach was a passive BLE tag on every tool and a network of fixed receivers locating every tag in real time using Bluetooth Angle of Arrival. Groundplane designed and built the tag side (PCB, firmware, enclosure, CR2032 battery for months-long operation) and the adjustable receive-antenna enclosure on the anchor side, plus contributed to RF testing and locating-algorithm deployment.

What we built

• nRF52-series BLE tag: PCB design, firmware, and enclosure
• Tag inputs and outputs: button, status LED, and piezo buzzer for the audible find-it cue
• Impedance-matched chip antenna for a consistent BLE link from any tag orientation
• CR2032 battery for months-long field operation, no recharging required
• Adjustable enclosure for the u-blox AoA receive antenna on the anchor side
• RF testing and characterization across the tag and anchor link
• Locating-algorithm deployment support on the customer infrastructure

Hard parts

Months on a coin cell. A CR2032 holds about 230 mAh. To make months of operation work, every microamp of sleep current matters: deep sleep between BLE advertising windows, careful advertising-interval tuning, and the buzzer firing only on demand. The firmware was sized around that power budget from the first commit.

AoA on the shop floor. Bluetooth Angle of Arrival is sensitive to antenna placement, orientation, and the multipath environment of metal racks, machinery, and concrete. The adjustable receive-antenna enclosure lets the system be tuned per anchor on install. RF testing and algorithm deployment closed the gap from "it works on the bench" to "it works on the floor."

At a glance

Tag SoC

nRF52 series

Tag I/O

Button, LED, piezo buzzer

Tag antenna

Impedance-matched chip antenna

Tag battery

CR2032; months-long operation

Anchor antenna

u-blox AoA receive antenna in adjustable enclosure

Tag scope

PCB design, firmware, enclosure design, testing

Anchor scope

Adjustable antenna enclosure, RF testing, locating-algorithm deployment support

Status

Delivered to client

Outcome

Hardware, firmware, and both enclosures delivered to Consus. The engineering behind the tag, the coin-cell power budget, and the adjustable AoA receive enclosure transfers cleanly to any BLE-locating program that follows.