A robot system operating in an environment in which there is uncertainty and change needs to combine the ability to react with the ability to plan ahead. In a previous paper we proposed a solution to the problems of integrating planning and reaction: cast planning as adaptation of a reactive system, the planner-reactor approach. In this paper, we present our first experimental results from this approach. The results indicate that the planner-reactor approach is an attractive option for integrating planning and reaction in a robot system, allowing smooth, online updates to the behavior, of a reactive system with little time and behavior penalties accruing from the use of a planner.>

A robot system operating in an environment in which there is uncertainty and change needs to combine the ability to react with the ability to plan ahead. In a previous paper we proposed a solution to the problems of integrating planning and reaction: cast planning as adaptation of a reactive system. The planner, asynchronously tuning the reactor, decides on the appropriate parts of the reactor to be modified based on perceptions: information gathered in the reactor for the express purpose to inform the planner. In this paper, we show the benefits of using perception to adapt the reactor where it needs to be updated most and present our first experimental results from the planner-reactor architecture.>

The paper describes the software design approach and implementation of a stable grasp strategy to control a multifingered robot hand in a dynamic and uncertain environment. The overall design starts with a reactive system, called the Grasp Reactor, which measures the environment, and produces actions based on the environmental situations present. To improve the robustness of the Grasp Reactor, it is augmented with a deliberative component which executes concurrently with the Grasp Reactor. This component, called the Grasp Advisor, communicates global constraints to the Grasp Reactor to improve its decision making capability.

A robot system operating in an environment in which there is uncertainty and change needs to combine the ability to react with the ability to plan ahead. The authors had previously proposed a solution to the problems of integrating planning and reaction: cast planning as adaptation of a reactive system. They extend the theoretical treatment of the planner, including the effect of its iterated adaptation on the reactor, and describe the current implementation environment and a working example.>

Classical artificial intelligence planning is not sufficiently robust in uncertain and dynamic environments. Reactive approaches are robust in some environments-namely those for which they have been programmed. An approach that integrates a priori planning with reaction to increase robustness is presented. As motivation, a practical robot problem, the kitting robot, is presented. Solving this problem demands a system that can make timely and robust actions in an uncertain environment. A solution to the kitting robot problem in which planning is cast as adaptation of a reactive system to suit changes in the goals or environment is outlined. The reactive system (the reactor) is based on a formal model for representing flexible robot plans, the RS model. Thus, it was possible to formalize the mechanisms by which the planner improves the behavior of the reactor. This system was implemented to control a Puma-560 robot equipped with visual sensing.>

A methodology is presented for building integrated planning-reacting systems. The work is based on a formal process-based approach to building the reactive component; this makes it possible to formalize the concept of a planner improving a reactor. The planner design emphasizes how the planner can use the reactor to focus its reasoning, as well as how the reactor is guided by the planner to improve its behavior. The reactive component (the reactor) is based on a process-based model of robot computation, the RS model. This gives a powerful representation for actions with precise formal semantics. The duty of the planning component (the planner) is to adapt the reactor to suit a set of objectives and the possibilities afforded by the environment. Planner and reactor both operate continually, separately and in a complementary fashion.>