Proactive and Reactive Reconfiguration for the Robust Execution of Multi Modality Plans

The paper addresses the problem of executing a plan in a dynamic environment for tasks involving constraints on consumable resources modeled as numeric fluents. In particular, the paper proposes a novel monitoring and adaptation strategy joining reactivity and proactivity in a unified framework. By exploiting the flexibility of a multi modality plan (where each action can be executed in different modalities), reactivity and proactivity are guaranteed by means of a reconfiguration step. The reconfiguration is performed (i) when the plan is no more valid to recovery from the impasse (reactively), or (ii) under the lead of a kernel based strategy to enforce the tolerance to unexpected situations (proactivity). Both mechanisms have been integrated into a continual planning system and experimentally evaluated over three numeric domains, extensions of planning competition domains. Results show that the approach is able to increase the percentage of cases successfully solved while preserving efficiency in most situations

Plan repair for resource constrained tasks via numeric macro actions

The paper addresses the problem of plan repair for tasks involving mandatory constraints on consumable and continuous resources, modeled as numeric fluents. The approach starts by proposing a new notion of numeric macro actions allowing to handle - as an extension to the classical macro action formulation - conditions and operations not only on the propositional fragment, but also on the numeric one. By reasoning directly on the current plan, the paper shows two techniques for selecting useful macro actions. Such macro actions, toghether with the original actions model, are then used by an off-the-shelf numeric planner for a faster plan repair task. To evaluate the techniques and the contribution of numeric macro actions, we experimented the approach on several numeric planning domains using Metric-FF as off-the-shelf planner. Results show that both strategies enhance the performance of the same planning system without macro actions. Even, one of the strategies turns out to be very competitive also with the specialized plan repair system LPG-ADAPT, both in terms of cpu-time, and stability of the repaired plan

Plan Repair for Resource Constrained Tasks via Numeric Macro Actions

1The paper addresses the problem of plan repair for tasks involving mandatory constraints on consumable and continuous resources, modeled as numeric fluents. The approach starts by proposing a new notion of numeric macro actions allowing to handle - as an extension to the classical macro action formulation - conditions and operations not only on the propositional fragment, but also on the numeric one. By reasoning directly on the current plan, the paper shows two techniques for selecting useful macro actions. Such macro actions, toghether with the original actions model, are then used by an off-the-shelf numeric planner for a faster plan repair task. To evaluate the techniques and the contribution of numeric macro actions, we experimented the approach on several numeric planning domains using Metric-FF as off-the-shelf planner.Results show that both strategies enhance the performance of the same planning system without macro actions. Even, one of the strategies turns out to be very competitive also with the specialized plan repair system LPG-ADAPT, both in terms of cpu-time, and stability of the repaired plan.restrictedrestrictedSCALA, ENRICOScala, Enric