Multi-robot systems are expected to underpin the future of automated infrastructure in various fields, including logistics and transportation. Despite the importance of multi-robot research, operating a large number of physical robots presents nontrivial challenges that exceed those encountered in simulation environments. These include communication saturation, the difficulties in real-time localization, detection of abnormal robot behavior, and the need for user-friendly interfaces to allow for effective state management. Collectively, they create a significant gap in the assumptions between lab-scale studies and deployable technologies in this field. Therefore, we developed a versatile testbed for multi-robot studies that can accommodate up to 100 differential-drive robots, called the 100-Mouse System. Our hallmark is scalability, while maintaining flexibility to allow researchers to test their ideas with actual robot fleets. This is a result of deliberately and integrally designed modules from both software and hardware perspectives, as well as a user interface, which is essential in large-scale experiments. As an application of this platform, we present a pattern formation task in a centralized manner, demonstrating the ability of the system to effectively accommodate large robot fleets.

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