Iris

Prototype

CAN infrared temperature sensor node

Iris v3.1 sensor node out of its enclosure, with the infrared sensor module at one end of the board and a threaded connector at the other

Iris is the small infrared sensor node used at each corner of the Sentinel network. It measures brake or tyre surface temperature and reports it over the CAN bus, and each node has its own address, so it can join any J1939 CAN bus and be read by any device listening on it. From v3.1, firmware is flashed over the same CAN bus, so sensors can be upgraded without removing them from the car. The v3.1 prototype has an enclosure that opens for development access, and the next version is planned as a sealed, potted unit and the last before release.

Prototype pre-release for track tests.

Type: Hardware
Status: Prototype
Compliance: Not certified
Repository licence: CC BY-SA 3.0 (hardware), firmware not published (binaries only)
Updated: 17 October 2026

GitHub repository

Specifications

Iris specifications
MCU	ESP32-C3
Sensor	Infrared temperature
Interface	CAN bus (J1939), unique address per node
Board	Custom PCB v3.1
Firmware updates	Over the CAN bus, without removing the sensor from the car
Enclosure	v3.1 prototype opens for development access
Next version	Sealed enclosure potted in thermally insulating epoxy resin, design target 1000 °C
Used with	Sentinel

Gallery

Iris v3.1 assembled in its blue 3D-printed enclosure, with brass threaded inserts and a 4-pin circular connector — Iris v3.1 assembled in its prototype enclosure.

The two halves of the Iris v3.1 enclosure laid out next to two sensor boards — The v3.1 enclosure opens for development access. The next version will be sealed and potted in thermally insulating epoxy resin, and is planned as the last before release.

The v3.1 board and the infrared sensor module before assembly.

Component side of the Iris v3.1 circuit board with the ESP32-C3, next to the infrared sensor module — The component side of the v3.1 board. Firmware now updates over the CAN bus, so a sensor can be upgraded in place on the car.