Reasoning over norm compliance via planning

Abstract

Norms are a way to provide some flexibility to the specification of acceptable actor behaviour in a shared context. Instead of viewing norms as static restrictions over an agent's conduct (and autonomy), the full power of normative specifications comes when norms are seen as guidelines that agents can use in their decision-making. In literature there is a lot of work on norm theories, models and specifications on how agents might take norms into account when reasoning, but many of them focus on the goal or intention selection and few of them apply the norms into the agent's plan generation. In this paper we present a norm-oriented agent that takes into consideration operationalised norms during the plan generation phase, using them as guidelines to decide the agent's future action path. In our work norms can be obligations or prohibitions which can be violated, and are accompanied by repair norms in case they are breached. To make norms influence plan generation, our norm operational semantics is expressed as an extension/on top of STRIPS semantics, acting as a form of temporal restrictions over the trajectories (plans) computed by the planner. In combination with the agent's utility functions over the actions, the norm-aware planner computes the most profitable trajectory concluding to a state of the world where the effects of all the active norms have been explored, including the repair norms. We use a simplified fire emergency scenario in order to demonstrate the usefulness of the framework, integrating the norm-aware planner to 2APL agent architecture. We depict possible outcomes depending on criteria such as time and danger. © Springer-Verlag 2013.