SEAMLESS: Radio Metric Aware Multi-Link Transmission for Resilient Rescue Robotics

Wireless communication technologies are designed to cover specific scopes of use cases and, therefore, possess strengths and weaknesses inherent to their designated application area. As a critical enabler for robotic remote operations, wireless communications are expected to perform optimally, sometimes even in situations outside the respective technology's intended deployment scope. Since a single technology can hardly ever meet the high requirements, various approaches to aggregate multiple communication links, so-called multi-links, have emerged in recent years. In this paper, we propose the novel open-source multi-link solution SEAMLESS to provide reliable connectivity in the context of rescue robotics in search and rescue missions. It improves flexibility by supporting general internet protocol service tunneling and multiple schedulers. As wireless technologies can not be assessed solely on the basis of network key performance indicators, an open radio monitoring interface is implemented, allowing radio metric aware scheduling. A comprehensive evaluation is carried out in two experiments, in both indoor and outdoor testing sites. The results showcase the benefits of the proposed radio metric multi- link scheduling by demonstrating a reliable high-resolution video transmission in challenging radio environments over Wi-Fi 6 and public cellular 5G.