We include it here, behavior.

This article reviews research in the development of plan generation systems. Our goal is to familiarize the reader with some of the important problems that have arisen in the design of planning systems and to discuss some of the many solutions that have been developed in the over 30 years of research in this area. In this article, we broadly cover the major ideas in the field of AI planning and show the direction in which some current research is going. We define some of the terms commonly used in the planning literature, describe some of the basic issues coming from the design of planning systems, and survey results in the area. Because such tasks are virtually never ending, and thus, any finite document must be incomplete, we provide references to connect each idea to the appropriate literature and allow readers access to the work most relevant to their own research or applications.

The sequence of mating operations that can be carried out to assemble a group of parts is constrained by the geometric and mechanical properties of the parts, their assembled configuration, and the stability of the resulting subassemblies. An approach to representation and reasoning about these sequences is described here and leads to several alternative explicit and implicit plan representations. The Pleiades system will provide an interactive software environment for designers to evaluate alternative systems and product designs through their impact on the feasibility and complexity of the resulting assembly sequences.

In this article, we present Spar (simultaneous planner for assembly robots), an implemented system that reasons about high-level operational goals, geometric goals, and uncertainty-reduction goals to create task plans for an assembly robot. These plans contain manipulations to achieve the assembly goals and sensory operations to cope with uncertainties in the robot's environment. High-level goals (which we refer to as operational goals) are satisfied by adding operations to the plan using a nonlinear, constraint-posting method. Geometric goals are satisfied by placing constraints on the execution of these operations. If the geometric configuration of the world prevents this, Spar adds new operations to the plan along with the necessary set of constraints on the execution of these operations. When the uncertainty in the world description exceeds that specified by the uncertainty-reduction goals, Spar introduces either sensing operations or manipulations to reduce this uncertainty to acceptable levels. If Spar cannot find a way to sufficiently reduce uncertainties, it augments the plan with sensing operations to be used to verify the execution of the action and, when possible, posts possible error-recovery plans, although at this point, the verification operations and recovery plans are predefined.

In First International Conference on Expert Planning Systems, pp. 70–75. Institute of Electrical Engineers.

Computational Intelligence, 6 (4), 232-46

Computational Intelligence, 6, 12–24

Proc. AAAI-90.

"We describe a robot control architecture which combines a stimulus-response subsystem for rapid reaction, with a search-based planner for handling unanticipated situations. The robot agent continually chooses which action it is to perform, using the stimulusresponse subsystem when possible, and falling back on the planning subsystem when necessary. Whenever it is forced to plan, it applies an explanation-based learning mechanism to formulate a new stimulus-response rule to cover this new situation and others similar to it. With experience, the agent becomes increasingly reactive as its learning component acquires new stimulus-response rules that eliminate the need for planning in similar subsequent situations. This Theo-Agent architecture is described, and results are presented demonstrating its ability to reduce routine reaction time for a simple mobile robot from minutes to under a second."In AAAI-90, Vol. 2, pp. 1051– 1058

Second, These sections describe how Phoenix agents there are motivating issues, of plan in real time but do not provide the which the foremost is to understand minute detail that is offered elsewhere (Cohen how complex environments et al. forthcoming). The next section illustrates constrain on the design of Phoenix agents controlling a forest fire. We seek general The last section describes the current status of rules that justify and explain the project and our immediate goals. The terms in these rules describe The Phoenix task is to control simulated characteristics of environments, forest fires by deploying simulated bulldozers, tasks and behaviors, and the crews, airplanes, and other objects. We discuss architectures of agents. Phoenix Environment, Layers 1 and 2 but Phoenix is a commentary on the Phoenix Simulator. In the following pages, we describe Phoenix from the perspective of our technical aims and motives. The second section describes the Phoenix task--controlling simulated forest fires-- and explains why we use a simulated environment instead of a real, physical one. The two lowest layers of Phoenix, described in The Phoenix Environment, Layers 1 and 2, implement the simulated environment and maintain the illusion that the forest fire and agents are acting simultaneously. Above these layers are two others: a Figure 2. Fire at 12:30 Bulldozers are Close to organization of multiple Meeting at the Fire Front. The left pane displays the real world; the right pane displays fireboss sees it. Firefighting objects are also and other agents are semiautonomous.