The MMP: A Mixed-Initiative Mission Planning System for the Multi-Aircraft Domain

The Universität der Bundeswehr München is conducting research in the field of single-operator multi-aircraft guidance. This article describes the Mixed-initiative Mission Planner (MMP) as far as requirements, concept, design and implementation are concerned. The MMP is applied to a timeconstrained multi-aircraft in-flight mission planning problem. It works in conjunction with a cognitive assistant system for an Uninhabited Aerial Vehicle (UAV) operator, who generates and modifies multi-aircraft mission plans incrementally. The assistant system is able to evaluate, complete, and generate such plans with the aid of the MMP and to communicate with the operator, which results in a mixedinitiative planning approach. Mixed-initiative planning systems need to be able to evaluate the partial or complete human plans as well as the problem itself. For this reason there are two instances of the MMP in our system design. One is configured as a slave to the human input to assume what the human is planning and the other as a free planner that generates reference plans. The assumed human plan includes temporal information about already planned and future tasks, and it can be compared to the reference plan by the assistant system, allowing it to decide whether and when to take initiative. The MMP prototype implementation consists of a Planning Process Manager that dynamically generates problem descriptions, a freely available PDDL 2.2 compatible planner, and multiple domain descriptions.