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Techniques & Tools for Three Dimensional Visualisation & Communication of Spatial Agent-Based Models

Andrew Crooks & Andrew Hudson-Smith Centre for Advanced Spatial Analysis


Outline

Outline • Introduction & Context. • Tight Coupling: Agent-Based models with systems: –ABM within 3D Studio Max. –ABM within Second Life. • Loose Coupling: ABM in NetLogo and visualisation in 3D Studio Max. • Conclusion and further work.


Introduction

Introduction/Context • Visualisation is the main way to how we interact with computers and helps with the communication of models. – This relates to the notion that models that generate spatial or physical predictions must ‘look right’. • This talk explores how advances in graphic card technology, networked communication allow us new ways to create and visualise agent-based models. – Models presented act as ‘proof of concept’. • Explores the potential of linking to other models at CASA. – Such models provide a mechanism for outreach and communication, with the potential to enhance the publics understanding of science. • Provide a sense of location & space. • Model development coincides with the growth in 3D Cityscapes and Digital Earths: – Could agent-based models be used to populate virtual cities?


ABM within 3D Studio Max

Tight Coupling: Creating Agent-Based Models in 3D Studio Max • 3D Studio Max is a modelling, animation and rendering package - GI data can be imported into it. • Allows for the creation of basic 3D Agent-based models. – Crowd Numbers + Delegate Rules = 3D Agent-Based Model (Crowd and Delegate system). – Can be linked to physics engines such as Havok therefore easy to add in dynamics etc. • Enables high quality output (e.g. 3D city models) as well as real time previews. • Output to game engines such as Crysis.


ABM within 3D Studio Max

Basic ‘Wander’ Simulation


ABM within 3D Studio Max

Agents Aware of Each Other and Space


ABM within 3D Studio Max

Basic Path Follow and Rules: Traffic ‘Wave’ Effect

More Info: http://www.youtube.com/watch?v=Suugn-p5C1M New Scientist Article: http://technology.newscientist.com/article/dn13402


Agents in the City: Avoidance of other objects


ABM within 3D Studio Max

‘Reactor’: Havok Physics Engine in 3D Studio Max

• Objects are given mass, can also add friction, elasticity, density. • Could be used to represent real world physics (e.g. crushes, car crashes etc.).


Agent Street - Agent-Based Modelling in Second Life

Communicating, Outreach and Collaboration of Agent-Based Models. At CASA SL is used as a online urban laboratory -collaboratories, to explore issues pertaining to urban planning & public debate in a visually 3D collaborative environment.

Hudson-Smith, A., Crooks, A. T., Gibin, M., Milton R. and Batty, M. (under review) Neogeography and Web 2.0: Concepts, Tools and Applications, Journal of Location Based Services.


Agent Street - Agent-Based Modelling in Second Life

Agent-Based Models in Second Life • Exploring SL potential for 3D ABM for social scientists. • SL and ABM are both artificial worlds. • Created 3 different types of agentbased models as pedagogic demonstrators. • Demonstrates: – The potential of how experts, model builders and the non specialist can view, interact and discuss agentbased models. – Symbolic (i.e. mathematical modelling) inside of Iconic models (i.e. geometric modelling). Crooks, A., Hudson-Smith, A & Dearden, J. (under preparation) Agent Street: Agent-Based Modelling in Second Life


Agent Street - Agent-Based Modelling in Second Life


Agent Street - Agent-Based Modelling in Second Life

Prototype Pedestrian Evacuation Model • Shows how we can test ideas and hypothesis of phenomena which are not easy to do in the real world (i.e. set buildings on fire). • As with all our models it is a ‘proof of concept’. • Walking speed governed by surrounding density. • Stationary obstacles such as tables and walls as well as nonstationary obstacles (i.e. other pedestrians) have effect on occupant movement (Castle, 2007).


Agent Street - Agent-Based Modelling in Second Life


Agent Street - Agent-Based Modelling in Second Life

Simple Layout Second Life

Path Traces

Can explore how basic room configurations can impact on evacuation time in an event of an alarm being sounded

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Agent Street - Agent-Based Modelling in Second Life

1st Floor

Multi-Floor Layout

Ground Floor


Loose Coupling: Importation of GIS Data into NetLogo

• Easy to create models -allows for rapid prototyping of ideas but limited visualisation capacity. • NetLogo for modelling, 3D Studio Max for visualisation.


Loose Coupling: NetLogo with 3D Studio Max

Basic traffic grid model from NetLogo


Loose Coupling: NetLogo with 3D Studio Max


Loose Coupling: NetLogo with 3D Studio Max


Conclusion

Conclusion - next steps • Shown a range of models in 3D agent-based models -all have a spatial element. • 3D Max models: – Highly visual but essentially ‘black box’ models. – Loose coupling with NetLogo has potential. • The SL models demonstrate: – Different types of agent-based models can be created in SL. – The ability to easily share and visualise complex models to the non experts therefore the potential to significantly impact on the outreach of ABM. – Potentially provides a medium for online model building (or collaboratories).

– There are problems with SL: • Need of land, deficiencies of the internet (e.g. bandwidth, package delivery etc.), server side delays, limited script sizes.

• The future/next steps? – Attempt to build models based on real locations via loose coupling approaches, explore other visualisation tools (e.g. Blender), and graphic programming technology (e.g. DirectX, OpenGL).


Thank you for listening! Welcome comments, questions and suggestions.

gisagents.blogspot.com & digitalurban.blogspot.com We would like to thank Joel Dearden & Ateen Patel & GLA Economics


Visualisation and Communication of Spatial Agent-Based Models