A track-side optoelectronic sensor tells the driver when the train is correctly positioned, over a LoRa radio link to a receiver unit in the cab.
Detectionretroreflective
LinkLoRa point-to-point
Statusfield-validated
Role
Full chain: electronics, firmware, CAD, 3D printing and field validation
Context
MESEA · field tool
Stack
Raspberry Pi
LoRa
Python
Onshape
3D printing
01Retroreflectoron the train
02Track-side sensoroptoelectronic
03TransmitterRaspberry Pi + LoRa HAT
04LoRa linkno cellular coverage
05Cab receiverLED indicators
Fig. 04.1 — System overview
The problem
Drivers sometimes have to stop a train at a precise position, in zones with no cellular coverage at all. The information has to reach the cab over its own radio link, and be readable at a glance.
How it works
A track-side optoelectronic sensor works with retroreflectors to detect the train's position.
A point-to-point LoRa link carries the status to a receiver unit in the driver's cab.
The cab unit drives clear LED indicators so the driver can position the train without guesswork.
Build
Electronic schematics, Raspberry Pi boards with LoRa HATs.
Enclosures designed in Onshape and 3D printed for mounting and weather protection on site.
Validation & documentation
Validated in the field, and delivered with full documentation — schematics, CAD files and a deployment guide — so the teams can install and maintain it without me.