Platooning LEGOs: An Open Physical Exemplar for Engineering Self-Adaptive Cyber-Physical Systems-of-Systems

Many modern systems interact with both cyber and physical environments. They are complex systems in which multiple constituent systems work together to achieve higher-level goals. These systems are called cyber-physical systems of systems (CPSoS). As the interest in CPSoS, such as platooning vehicles and robot-based smart factories, increases, engineering for adaptive goal achievement of CPSoS is needed. Common exemplars of a research community can facilitate research; however, existing exemplars of CPSoS are mostly based on virtual simulations. Although this allows researchers to share experimental scenarios and environments, it has the limitation that it is difficult to conduct experiments that reflect actual physical environments. To overcome this limitation, we propose a physical exemplar of an industrial CPSoS, called Platooning LEGOs, which employs platooning technology that is actively being developed by the autonomous driving industry. A platoon, in which independent vehicles drive together, achieves SoS-level goals through adaptive behavioral decisions of the vehicles. This exemplar provides a physical experimental environment that can be implemented with LEGOs. A simple LEGO assembly allows the use of real data from sensors and actuators, facilitating a focus on software engineering without considerable mechanical knowledge. Moreover, as this is an open exemplar, researchers can implement the same physical experimental environment with a limited budget and expand its physical or software elements. We provide system descriptions, physical and software implementation manuals, and sample experimental results of Platooning LEGOs.