Integrated Wheel Sensor Communication using ESP32 -- A Contribution towards a Digital Twin of the Road System

--While current onboard state estimation methods are adequate for most driving and safety-related applications, they do not provide insights into the interaction between tires and road surfaces. This paper explores a novel communication concept for efficiently transmitting integrated wheel sensor data from an ESP32 microcontroller . Our proposed approach utilizes a publish-subscribe system, surpassing comparable solutions in the literature regarding data transmission volume. We tested this approach on a drum tire test rig with our prototype sensors system utilizing a diverse selection of sample frequencies between 1 Hz and 32 000 Hzto demonstrate the efficacy of our communication concept. The implemented prototype sensor showcases minimal data loss, approximately 0. 1 % of the sampled data, validating the reliability of our developed communication system. This work contributes to advancing real-time data acquisition, providing insights into optimizing integrated wheel sensor communication. A. Motivation Intelligent transportation systems rely on sensors to estimate their own state and that of surrounding objects. Traditional onboard methods, using inertial measurement units (IMUs), wheel encoders, and Global Navigation Satellite Systems (GNSS), operate at frequencies from 1 Hz to several hundred Hz, providing sufficient accuracy for trajectory reconstruction and stability control. However, these methods do not directly capture tire-road interactions. Even safety systems like an-tilock brake (ABS) and electronic stability programs (ESP) rely on conservative assumptions about forces and friction rather than real-time estimation.