Got it, here’s a quick sensor stack that’ll let you crunch the numbers fast: - **Wearable IMUs** (3‑axis accelerometers + gyros) on every recruit – they give you step count, stride length, and any sudden jolts that might mean a tripped foot. - **GPS trackers** (tiny BLE tags) for line‑of‑sight movement, distance covered, and speed profile. Just make sure the antenna placement on the helmet keeps the link alive. - **Chest‑strap heart‑rate monitors** – the classic metric for fatigue. If you want a deeper dive, add a skin‑temperature sensor so you can spot a heat‑stroke risk before it happens. - **Ambient environment probes** – temperature, humidity, wind speed. These are the background variables that explain why a squad stalls. - **Pressure mats** on the ground – if you want to measure load distribution during a march or a simulated battle stance. All of them should publish to a local MQTT broker. Set up a tiny Node‑RED flow that tags each packet with a timestamp, feeds the data into a lightweight InfluxDB instance, and pushes real‑time dashboards to a dedicated screen in the command tent. If you want to get fancy, use a simple k‑means clustering on the IMU data to flag unusual gait patterns that might indicate injury. That’s the bread and butter. Keep the firmware tight and your power budget in check, and you’ll have the data you need without cloud lag. Happy training.