To weigh large items like bicycles or suitcases, standard scales are often impractical. This solution uses up to four small scales that transmit weight measurements to an ESP32 module, which then displays the aggregate total. For the wireless transmission, the lightweight ESP-NOW communication protocol is used.

The Project

I recently wanted to weigh my bicycle and found the conventional method — weighing yourself on a bathroom scale with and without the bike and calculating the difference — quite cumbersome. Similarly, it is frustrating to comply with airline weight limits when traveling with oversized luggage or bike bags. My solution employs several compact, interconnected scales; they transmit real-time data to a receiver wirelessly, which sums up the values.

In this project, each of the four scales has a 10-kg capacity (depending on the strain gauge used), providing a total limit of 40 kg. Higher weight ranges are easily achievable with alternative sensors. The system ...