I have an unorthodox suggestion: get a bicycle rear radar like the Garmin Varia. They communicate via Bluetooth LE incoming cars, their count, and an average sp

I have an unorthodox suggestion: get a bicycle rear radar like the Garmin Varia. They communicate via Bluetooth LE incoming cars, their count, and an average speed (in a set of ranges like 0-15km/h, 15-30km/h, …). Mount this with a usb cable somewhere, add an ESP32 or anything with Bluetooth somewhere else to accumulate.