University Programs in Computer Aided Engineering Design and Manufacturing. (UPCAEDM'92), Tennessee Technological University. D.C.Brown (1992) ...
From: AAAI Technical Report WS-93-07. Compilation copyright © 1993, AAAI (www.aaai.org). All rights reserved.
Exploring the role of single function agents in negotiation
D. C. Brown AI Research Group ComputerScience Department WorcesterPolytechnic Institute Worcester MA01609
USA
BRIEF POSITION PAPER Despite somevery interesting workon computationalmodelsof negotiation such as that by Sycara [1990], Lander & Lesser [1992], Klein [1991], Werkman [1992], Kannapan& Marshek [1992], and others we feel that there is still muchto be done. Despite having contacted manypeople directly and via email, the first surprise is that there appear to be very few implementations, few computational models, little evaluation of the systems, and no comparativeevaluation. As our group is newto the area, we are first doing a survey of workon Negotiation. Weare attempting to characterize most of the mainresearch efforts by developingand using a set of attributes. Theseinclude the presence and role of a central agent; the amountof knowledge each agent has about other agents; the communication languageused; whetherthere is a global record of the design; the reasons for conflict; whetherthe agents are cooperative; whetherthe agents are homogeneous;whether a design/negotiation history is kept/used; and the negotiationstrategies used. Ourmotivation for the research is the desire to build workingConcurrentEngineering(CE) systems. Withinthe last year wehavebuilt two systemswith manyCEcharacteristics. As it is difficult to producea precise description of CEon whichall researchers wouldagree, I will refrain from claiming that they are CEsystems. However,most wouldagree that the essential quality is that at designtime it is importantto considerthe impactof the designon aspects from later in the life-cycle, suchas packaging,or recycling. Oneof the systemsbuilt, the 13Dsystem[Bauschet al 1992][Victor et al 1993], used multiple cooperative intelligent agents to serve on a design team with a humandesigner. Togetherthey designed simple powderceramic components,using a conceptual design phase and a detailed design phase. Theagents were able to respondand assist in both the design phases, offering cost estimation, material selection, process simulation and inspection planning, for example. Therewere16 intelligent agents in I3D.
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The second system, called SNEAKERS [Douglas & Brown1993], was intended to be used during training courses to help educate users about the powerof CEand its importance. As such, it is a single-user system, with the other membersof the CEteam being simulated by expert systems (agents). The user designs a tower on the screen, according to some requirements,by selecting from, and specializing, parts offered by the system. As in I3D, the agents offer a variety of comments whichthe user can act on or ignore. Thesesystems have several things in common.Thoserelevant to this workshopare: they used intelligent agents, with each agent havinga single function; the agents are only allowedto activate in a fixed sequence. In these systemsall possibility of conflict, and hencenegotiation, wascompiledout by careful ordering of the agents and by careful groupingof the decisions being made.In a newversion of 13D(13D+),to address grouping, weare separating out the decisions into different agents, and, to addressordering, weare trying not to predefinetheir order of execution. The work in I3D+is currently in progress. It will provide a testbed for a variety of experiments with negotiation. Wewill also be constructing a customizable domain independenttestbed to with whichto experiment. In 13Dand SNEAKERS we experimented with single function agents. Agents were only able to perform one of a few simple roles [Brown1992]. The roles used included providing Advice,Analysis, Criticism, Estimation, Evaluation, Planning, Selection and Suggestion. These roles can be contrasted with the target about which they can makecomments.For I3D these include Material, Process, Manufacturing,Inspection, Cost, Reliability and Durability. Theroles and targets define a 2Dmatrix of possible agents, not all of whichare sensible. In I3D+we are trying to refine this further by considering another axis, point-of-view, thus classifying agents using a 3Dmatrix (i.e., role, target, point-of-view).For example,one agent might be Criticism of material (the Targe0 from the Point-of-view of cost. Note that, as before, not every entry is sensible. However,this systemallows us to quite precisely define everyagent in the system.It will also force us to be very explicit aboutwhateach agent knows, while allowing us freedomto implementthe agents in any wayappropriate, providedthey play their appointedrole. Weintend to extend this sort of analysis to apply to the knowledgeused in negotiation. Each role in the negotiation process will be played by a separate agent, with, for example,some beingresponsiblefor providingtrade-off knowledge,or keepingthe negotiation history. In this waywe hope to develop a detailed architecture that supports negotiation, but which will responddifferently whenprovided with different knowledge. Weexpect to learn a lot aboutthe roles of different types of knowledge in different negotiation schemes. Where grouping of decisions allowed us to avoid negotiation in I3D and SNEAKERS, this approachof strict separation will force us to face negotiation directly and in detail. It is alreadyclear that Critics andEstimatorsinteract in interesting wayswith the agents doing design (Advisors), allowing several waysto negotiate betweenthem. For example, critic can criticize an estimate: what do they negotiate about? Perhaps the methodof
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estimation? Or the data used? In this first round of investigation into negotiation we will study the architecture that supports negotiation, rather than negotiation strategies. Wewill mainly focus on using I3D as the testbed, modifyingand extending it as necessary. In the longer term, we are very interested in the use of design histories during negotiation, in case-based negotiation, in the use of trade-off knowledge, in comparative analyses of negotiation strategies, and in the opportunities for use of Learning during negotiation.
References J.J.Bausch, D.C.Zenger, D.C.Brown, R.Ludwig & R.D.Sisson (August 1992) Integrated Design and Manufacturing Strategies for Powder~ Processing Applications. Proceedings, University Programs in Computer Aided Engineering Design and Manufacturing (UPCAEDM’92), Tennessee Technological University. D.C.Brown(1992) Design. Encyclopedia of Artificial (Ed.), J.Wiley.
Intelligence,
2nd edn., S.C.Shapiro
R.E.Douglas, Jr. & D.C.Brown(1993) A Concurrent Engineering Demonstration System for use in Training Engineers and Managers. Proc. AI in Engineering Conference. S.M.Kannapan & K.M.Marshek (July 1992) A Schema for Negotiation between Intelligent Design Agents in Concurrent Engineering. In: D.C.Brown, M.Waldron & H.Yoshikawa (Eds.), Intelligent ComputerAided Design, Elsevier Science Publishers B.V. (North-Holland). M.Klein (1991) Supporting conflict resolution in cooperative design systems. IEEE Trans. Systems, Man, and Cybernetics, November/December,Vol. 21, No. 6, pp. 1379-1390. S.E.Lander & V.R.Lesser (Dec. 1992) Customizing Distributed Search among Agents with Heterogeneous Knowledge. Proc. 5th Int. Symp. on AI Applications in Manuf. & Robotics, Cancun, Mexico. K.P.Sycara (1990) Cooperative Negotiation Engineering Design. Springer Verlag.
in Concurrent
Design.
In: Cooperative
S.K.Victor, D.C.Brown, J.J.Bausch, D.C.Zenger, R.Ludwig & R.D.Sisson (1993) Using Multiple Expert Systems with Distinct Roles in a Concurrent Engineering System for Powder Ceramic Components. Proc. AI in Engineering Conference. K.J.Werkman (1992) Multiple Agent Cooperative Design Evaluation using Negotiation. J.S.Gero (Ed.), Artificial Intelligence in Design ’92, KluwerAcademicPublishers.
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