On the Formalism and Properties of Timing Analyses in Real-Time Embedded Systems

The advanced development of embedded computing devices, accessible networks, and sensor devices has triggered the emergence of complex cyber-physical systems (CPS). In such systems, advanced embedded computing and information processing systems heavily interact with the physical world. Cyber-physical systems are integrations of computation, networking, and physical processes to achieve high stability, performance, reliability, robustness, and efficiency [26]. A cyberphysical system continuously monitors and affects the physical environment which also interactively imposes feedback to the information processing system. The applications of CPS include healthcare, automotive systems, aerospace, power grids, water distribution, disaster recovery, etc.
Due to their intensive interaction with the physical world, in which time naturally progresses, timeliness is an essential requirement of correctness for CPS. Communication and computation of safety-critical tasks should be finished within a specified amount of time, called deadline. Otherwise, even if the results are correctly delivered from the functional perspective, the reaction of the CPS may be too late and have catastrophic consequences. One example is the release of an airbag in a vehicle, which only functions properly if the bag is filled with the correct amount of air in the correct time interval after a collision, even in the worst-case timing scenario. While in an entertainment gadget a delayed computation result is inconvenient, in the control of a vehicle it can be fatal. Therefore, a modern society cannot adopt a technological advance when it is not safe.