Sensor Mesh
A low-power mesh of room sensors for schools — mapping temperature, noise, and air flow without running new cabling. Built so students could assemble nodes themselves.
Challenge
One-off sensors are easy; a network that survives uneven Wi-Fi, budget constraints, and teenage curiosity is not. The goal was a repeatable kit: PCB, enclosure, firmware OTA, and a simple picture of each room on a dashboard — without turning the workshop into a networking course.
Approach
Custom boards around a common ESP module, sleep-heavy firmware, and a mesh layer that degrades gracefully when nodes wander. The physical design favors hand-assembly: generous pads, silkscreen hints, and a clip-together case so debugging doesn’t mean desoldering.
- Power budget first — months on battery where mains weren’t guaranteed.
- Assembly as a teaching moment, not a manufacturing hurdle.
- Observability in the workshop: blink patterns and serial logs that read like a story.
Outcome
A pilot network in two classrooms, with students building half the nodes and documenting what “normal” looked like for their rooms. The stack isn’t exotic; the point was reliability and repeatability — something the next cohort can extend instead of replace.