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Path Planning

Introduction

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Who am I?

Roland Geraerts Robotics background Research on path planning and

crowd simulation Assistant professor Software package

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Who are you?

Master GMTE? Course Motion and Manipulation? Interest in games? Why do you follow this course? Interest in thesis projects? Who has exciting hobbies?

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Learning goals of the course

To become an expert in path planning and crowd simulation Study and discuss many papers

To understand the limitations of current techniques Determine the limitations and open problems in the papers

To become a very critical reader Hand in many assessments of papers Actively participate in discussions

To understand the state-of-the-art in current games and how this could be improved Study path planning and crowd simulation in existing games Write paper about the applicability of new techniques (*)

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Learning goals of the course

To understand crowd simulation frameworks Follow the workshop Compare collision-avoidance methods in a framework (*)

To improve further upon your scientific skills Participate in discussions and lead them Give better presentations Know how to set up experiments better (workshop) Write better review reports and assessments

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Why this course

Path planning and crowd simulation are important research topics in Utrecht Roland Geraerts, Frank van der Stappen, Marc v. Kreveld,

Wouter van Toll, Norman Jaklin, Arne Hillebrand, Sybren Stüvel, Relation to animation research (Arjan Egges)

Many research projects Commit STW Demonstrator

Thesis and PhD projects Much interest from the industry

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Practical aspects

Meetings Tuesday 9.00 - 10.45 in BBG 2.05 Thursday 15.15 - 17.00 in BBG 0.83

Presence is mandatory If you cannot come for whatever reason

• Hand in abstracts on paper before the meeting

Website http://www.cs.uu.nl/docs/vakken/mpap/ Check the schedule Check regularly for announcements and changes Download papers Find the secret page

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Assignments

Present one paper (the group is quite big) Contents (10 min.), critical review (15 min.),

discussion (15 min.) Write paper abstracts/assessments

When presenting, only read the other paper One page per paper

• Short abstract in your own words• Critical assessment

– Main limitations and open problems– Surprising and innovative elements– Do the authors claim too much, make many assumptions, draw

conclusions that are too general, not correctly setup their experiments?

• Three questions or points for discussion Hand in the two pages (on paper) on the day of the

presentation• Use headings: Summary, Assessment, Questions

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Assignment 1

Study path planning/crowd simulation in a modern game Deliberately try to create problems

• Destroy objects/buildings• Stand in the way of moving characters• Park a car on the sidewalks• Let a character follow you while traversing a `difficult route’

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Assignment 1

Collect video footage of issues related to Natural crowds that fill up the game to make it more realistic

• Strange behavior near the player• Unnatural behavior elsewhere• Uniform behavior for different entity types• …

Collision-avoidance with entity, group of entities, or obstacle; e.g. a character

• gets blocked;• takes an illogical detour;• does not avoid congested areas;• passes through an obstacle or another character;• makes sudden undesired directional changes;• does not look ahead;• walks through a group of interacting characters.

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Assignment 1

Procedure Investigate what goes wrong Make one video

• Convert the video to a WMV-file• Use e.g. Fraps for recording the movie• Compress your movie (mpeg4), and use a high bit-rate for the movie• Use a 720p or 1080p resolution if possible• You may include multiple examples• Don't use transitions (e.g. fades) between clips or overlays (e.g. text)• The shorter, the better. It should capture the problem’s essence

Present 3 slides next Thursday (September 10) for discussion• Name of the game, your names, picture, type of game• The video• Description of what goes wrong and why (according to you)• Send a link to the files to me before 10:00 (September 10)• Explain and discuss (5 minutes)

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Some results of a previous assignment

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Assignment 2

Choose between writing a paper or a comparative study Deadline

• October 30 (23.59)• Use the Submit system

Paper on path planning/crowd simulation in games• Based on the problems extracted from assignment 1• Write a paper (10 pages) on how these problems can be solved• Audience: a recommendation for the programmer of the game• Try to be as critical on your own paper as you were on the papers

you have reviewed Compare the three collision-avoidance methods of our crowd

simulation framework• C++• A fair comparison is important• E.g. create the right scenarios and test the right set of parameters• Write a report

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Bonus points

Organize a well-conducted flash mob Yields a bonus of maximum 1 point Replay a game situation from assignment 1 Make recordings of the event and reactions of the people Hand in a movie and a small document You’re encouraged to work together Deadline: October 30

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Grading

Game study 10% Presentations 20% Abstracts 40% Paper/implementation 30%

To qualify for second chance exam The original mark should at least be a 4; Actively participate in at least 13/17 of the meetings; Write at least 17/22 abstracts; Give both presentations satisfactory.

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Grading

You cannot pass the course if you skip assignment 1 or 2; one of your presentations; 5 or more meetings (out of 18 meetings); 6 or more abstracts (out of 22 abstracts).

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Workshops

Workshop 1 September 17 Crowd simulation

• Software and framework• Collision-avoidance algorithms• C++• (Experimental research)

Workshop 2 October 22 A* Search

• Understand the A* algorithm• Reason about its properties• Apply it to a range of problems

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ScheduleWeek Date Topic Speaker Deadline

36 Sep 3 Introduction Teacher Read paper 0

37 Sep 8 Path planning in games Teacher

Sep 10 Current problems in games I Everyone Assignment 1

38 Sep 15 Current problems in games II Everyone

Sep 17 Workshop I Teachers

39 Sep 22 Path planning Students Abstracts

Sep 24 Path planning Students Abstracts

40 Sep 29 Social force-based models Students Abstracts

Oct 1 Velocity-based models Students Abstracts

41 Oct 6 Vision-based models Students Abstracts

Oct 8 Flow Students Abstracts

42 Oct 13 Flow Students Abstracts

Oct 15 Crowds Students Abstracts

43 Oct 20 Crowds, behavior Students Abstracts

Oct 22 Behavior, massive crowds Students Abstracts

Oct 22 Workshop II Teachers

44 Oct 27 Evaluation and validation Students Abstracts

Oct 29 Evaluation and validation Students Abstracts, assignment 2

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What we study in the course

Methodology/framework that solves these problems Developed in Utrecht (still in development) Applications (characters, cameras, groups, crowds, …)

Local character behavior How do people walk toward locations? How do they avoid each other? Must a path planning algorithm compute a path?

Crowd behavior Flow models Planning approaches Massive crowds Validation of crowd motions