1 / 29

Hierarchical Model for Real-Time Simulation of Virtual Human Crowds

This article by authors Soraia Raupp Musse and Daniel Thalmann, published in 2001, presents a hierarchical ViCrowd framework for real-time simulation of virtual human crowds. It explores scripted, reactive, and user-guided behaviors in controlling crowds, emphasizing knowledge, beliefs, and intentions. The article discusses crowd modeling challenges, different crowd control types, and ViCrowd structure to enable group interactions in real-time simulations. It also highlights related work on behaviors like flocking, following, goal changing, attraction, repulsion, split, space adaptability, and safe-wandering. Future work includes enhancing the ViCrowd script language with Python and implementing panic and emergency behaviors.

shellie-kelly
Télécharger la présentation

Hierarchical Model for Real-Time Simulation of Virtual Human Crowds

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Bart van Greevenbroek Hierarchical Model for Real Time Simulation of Virtual HumanCrowds

  2. Overview • Article • Authors • ViCrowd • Experiments • Assessment

  3. The Authors SoraiaRauppMusse Daniel Thalmann

  4. The Article • Published in 2001 • Cited 229 times • Cited by “Finding Paths for Coherent Groups Using clearance” (no 6 on our list) by Arno kamphuis and Mark Overmars

  5. Controlling a Crowd • Scripted behaviors • Reactive behaviors • User-guided behaviors

  6. Hierarchy

  7. ViCrowd • Behavioral based multi-level framework • Used to simulate crowds in real time • Script-based language.

  8. Knowledge, Beliefs and Intentions • Knowledge (information about the world) • Beliefs (states of emotion) • Intentions (goals)

  9. Events • Can change the knowledge, beliefs or intentions of an agent • And thus the behavior • Example: A door closes, the knowledge that the door closes changes, agents will not go through that door. • Example: A bomb goes off, agents within a radius panic, and behavior is altered.

  10. Main Problems • Modeling of crowd information, also concerning the distribution of groups • Different levels of realism • Required Structure to provide interaction between groups of agents in real time

  11. Related work

  12. Different Types of Crowd Control

  13. Priority

  14. High level • Flocking • Following • Goal Changing • Attraction • Repulsion • Split • Space adaptability • Safe-Wandering

  15. Flocking • the agents from the same group share the same list of goals; • They walk at similar speeds; • They follow the paths generated as showed • One agent can wait for another on arrival at a goal when another agent from the same group is missing.

  16. Following • A group can follow another group by sharing the same goals, either temporary or permanently.

  17. Goal Changing • Agents can change groups, and this is influenced by the relationship value with each agent in the group (value between 0 and 1) • Agents have a leadership ability value, which is also taken into account • If an agent has a higher relationship with another group, it will join that group. If the leadership value is high enough

  18. Attraction • The user can paint regions where the groups must be at a certain point, and the orientation can be influenced as well. • Groups are normally attracted to attraction points

  19. Repulsion • Groups are repulsed by obstacles and each other (similar to the social force model)

  20. Split • Groups can split randomly

  21. Space Adaptability • The group wants to occupy all the walking space, using a bezier curve:

  22. Safe-Wandering • Using a procedural method, the agents predict collisions using collision detection between two lines

  23. Results (1) • Scripted Behavior (SB) • Reactive Behavior (RB) • Guided Behavior (GB)

  24. Results (2)

  25. Results (3)

  26. Future work • Improving viCrowd script language by integrating Python • Panic and Emergency Behaviors

  27. The Good • High level of compatibility with other methods • Very flexible system • User has control over groups if needed • Groups are essential for a realistic crowd, so its good to focus on groups • Knowledge, Beliefs and Intentions is a well-known paradigm in the AI field

  28. The Bad • Performance is not awe-inspiring • Exact formulae are missing • No system specs are given, which makes comparison with other methods difficult • A collection of simple motions are possible, but what about complex motions? • Seeing as groups follow attraction points, Oscillations can occur.

  29. The ugly • The site with examples they mentioned, does not work. • Figures are sloppy, some text is cut off. • Meaningless pictures. If something is happening in the experiment involving motions, draw arrows or make the motion obvious. • In general, they go all over the place.

More Related