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Unmanned aircraft systems are expected to provide both increasingly varied functionalities and outstanding application performances, utilizing the available resources. In this paper, we explore the recent advances and challenges at the intersection of real-time computing and control and show how rethinking sampling strategies can improve performance and resource utilization. We showcase a novel design framework, cyber-physical co-regulation, which can efficiently link together computational and physical characteristics of the system, increasing robust performance and avoiding pitfalls of event-triggered sampling strategies. A comparison experiment of different sampling and control strategies was conducted and analyzed. We demonstrate that co-regulation has resource savings similar to event-triggered sampling, but maintains the robustness of traditional fixed-periodic sampling forming a compelling alternative to traditional vehicle control design. 

In this paper we develop four methods for proving stability for a subclass of co-regulated systems - finite-state, co-regulated systems with restrictions on possible sampling rates. "Co-regulation" is a control strategy we previously developed wherein cyber and physical effectors are dynamically adjusted in response to holistic system performance. The cyber effector, sampling rate, is adjusted in response to off-nominal conditions in the controlled system, and the physical effector adjusts control outputs corresponding to the current (changing) sampling rate. The resulting computer-control system is a discrete-time-varying system with changing zero-order holds and sampling periods, and unknown delays over discrete intervals. This makes performance guarantees such as stability difficult to obtain.We address this difficulty by drawing from specialized results in the control community to develop four methods for proving asymptotic stability of finite-state, co-regulated systems. Each successive method relaxes the assumptions needed to guarantee stability. This lays the groundwork for a more all-encompassing analytical framework for co-regulated systems. We use the results to demonstrate stability for a co-regulated multicopter unmanned aircraft system.