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IEMI Labs
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IndustrialDesign complete (stages 1–6), not built

PPE Gate Prompt

A light and a spoken PPE reminder at the door, before people walk in

At a warehouse, plant or yard door, a light tower turns green, amber or red and says which PPE the door requires, using a bought camera and the shared IEMI hub; the site sees anonymous prompt counts by door and shift.

Who buys it
EHS or site manager at a distribution centre, 3PL warehouse or manufacturing plant (1–5 sites).
Why it pays
About $5k a year per site of supervisor reminder time (est.), plus an anonymous evidence pack for the PPE programme. A reminder aid only; no claim of avoided fines or injuries.
Target price
$1,290 site starter + $49/month; extra door $449 + $19/month (target)
First-minute wow
Walk towards the dock door without a hard hat: within about a second the tower turns red and says 'Hard hat required. Casco obligatorio.' Put one on and it turns green. Nobody is named or recorded.
See the CAD designConcept page
PPE Gate Prompt concept: the idea and where each part goes
The concept. The CAD design is below, under Printable CAD.

What the research found

And how this design answers it

  • Plant-wide monitoring against Intenseye, Spot AI and i-PRO → a prompt at the door, to the person, in the moment
  • $899 all-in-one head → about $85 Prompt Tower plus a bought IP66 camera on the shared hub
  • Dry-contact output invited misuse as an interlock → deleted; fail-visible amber, never green when the check is down
  • Harness 'check' a gate camera can't prove → amber-only beta, off by default
  • False red prompts → red only on a clear head view in 4+ frames; amber means 'couldn't check'
  • Privacy and labour objections → no identity, no clips by default, anonymous 5-minute counts, English and Spanish notices

Use case

Truck driver at the dock door

Visiting truck driverReceiving leadEHS manager

  1. 01Trigger: the radar sees someone approaching the driver door, inside 5 m
  2. 02Detection: the hub sees a vest but no hard hat in 5 frames of the camera substream
  3. 03Prompt: the tower turns red and says 'Hard hat and hi-vis required beyond this door' in English and Spanish
  4. 04Action: the driver takes a loaner from the hook; the tower turns green and the count is logged with no image

Outcome: The reminder happens at the door, and the receiving lead doesn't stop work to chase it

How it works

Architecture

  1. 01

    Sense: bought ONVIF PoE camera on the approach; 24 GHz radar in the tower for approach and distance

  2. 02

    Decide: Edge Hub runs a YOLOv8n PPE model on Hailo, tracks people and decides green, amber or red per door rules

  3. 03

    Prompt: local MQTT to the tower in under a second; NeoPixel windows and EN/ES voice prompts

  4. 04

    Report: anonymous 5-minute bins to the cloud; cluster alerts to the shift supervisor and a weekly report

Hardware

Real parts, buyable today

Bill of materials: about $85 per Prompt Tower (retail qty) plus about $50 per camera; shared hub about $371 (est.).

BlockPartWhy this part
Tower controllerWireless-Tag WT32-ETH01 (ESP32 + LAN8720 Ethernet)Wired, low-latency link to the hub; I2S and LED timing on chip
Light + voice3 × Adafruit NeoPixel Stick 8, MAX98357A I2S amp, 40 mm 3 W speakerReadable red/amber/green and spoken prompts in two languages
Approach sensorHi-Link HLK-LD2410C 24 GHz radarDistance and approach for gate priority; flags when the camera misses people
Power802.3af PoE splitter (12 V) + Pololu D24V22F5 buckOne cable; about 2 W typical
Camera + AIReolink RLC-510A class camera + IEMI Edge Hub (Hailo-8L for up to 4 doors)IP66 metal camera for about $50; one shared hub per site

Mechanical

Printable CAD

8 parts, generated from code and checked as closed solids. Pick a part to inspect it, or download the STL files to print.

See the CAD parts render
PPE Gate Prompt printable parts, rendered from the CAD
Render of the printable parts from the actual CAD. Not yet printed or photographed.

Loading the CAD…

Real CAD · drag to rotate · scroll to zoomReal CAD · swipe sideways

Open risks we are working on

  • Accuracy in real doorways with backlight from open dock doors or IR at night
  • Buyers treating a reminder aid as a safety system
  • Daylight readability of the light windows in direct sun
  • Model-compile and firmware toolchains are not in the Node-only lab

Design stage only: nothing on this page is for sale. Specifications and prices are targets.