Age of Actuated Information and Age of Actuation in a Data-Caching Energy Harvesting Actuator

In this paper, we extend the metric of Age of Actuation (AoA), and we propose the Age of Actuated Information (AoAI) within a discrete-time system that integrates data caching and energy harvesting (EH). AoA evaluates the timeliness of actions irrespective of the age of the information, while AoAI considers the freshness of the utilized data packet. We analytically characterize the performance of AoA and AoAI for the system at hand. Our findings show that while AoAI consistently decreases with increased data and energy packet arrival rates, AoA shows a counter-intuitive behavior, with a potential increase under limited data or energy availability. These metrics go towards the semantics of information and goal-oriented communications since they consider the timeliness of the utilized information to perform an action.