Announcements HW 6: Written (not programming) assignment. Assigned today; Due Friday, Dec. 9. E-mail to me. Quiz 4 : OPTIONAL: Take home quiz, open book. If you re happy with your quiz grades so far, you don t have to take it. (Grades from the four quizzes will be averaged.) Assigned Wednesday, Nov. 30; due Friday, Dec. 2 by 5pm. (Email or hand in to me.) Quiz could cover any material from previous quizzes. Quiz is designed to take you one hour maximum (but you have can work on it for as much time as you want, till Friday, 5pm). 1
Topics we covered Turing Test Uninformed search Methods Completeness, optimality Time complexity Informed search Heuristics Admissibility of heuristics A* search 2
Game-playing Notion of a game tree, ply Evaluation function Minimax Alpha-Beta pruning Natural-Language Processing N-grams Naïve Bayes for text classification Support Vector Machines for text classification Latent semantic analysis Watson question-answering system Machine translation 3
Speech Recognition Basic components of speech-recognition system Perceptrons and Neural Networks Perceptron learning and classification Multilayer perceptron learning and classification Genetic Algorithms Basic components of a GA Effects of parameter settings Vision Content-Based Image Retrieval Object Recogition 4
Analogy-Making Basic components of Copycat, as described in the slides and reading Robotics Robotic Cars (as described in the reading) Social Robotics (as described in the reading) 5
Reading for this week (links on the class website) S. Thrun, Toward Robotic Cars C. Breazeal, Toward Sociable Robotics R. Kurzweil, The Singularity is Near: Book Precis D. McDermott, Kurzweil's argument for the success of AI 6
Robotic Cars http://www.ted.com/talks/sebastian_thrun_google_s_driverless_car.html http://www.youtube.com/watch?v=lull63erek0 http://www.youtube.com/watch?v=fli_iqgcxbo 7
From S. Thrun, Towards Robotic Cars 8
Examples of Components of Stanley / Junior Localization: Where am I? Establish correspondence between car s present location and a map. GPS does part of this but can have estimation error of > 1 m. To get better localization, relate features visible in laser scans to map features. 9
Examples of Components of Stanley / Junior Obstacles: Where are they? Static obstacles: Build occupancy grid maps 10
Moving obstacles: Identify with temporal differencing with sequential laser scans, and then use particle filtering to track Particle filter related to Hidden Markov Model 11
Particle Filters for Tracking Moving Objects From http://cvlab.epfl.ch/teaching/topics/ 12
Examples of Components of Stanley / Junior Path planning: Structured navigation (on road with lanes): Junior used a dynamic-programming-based global shortest path planner, which calculates the expected drive time to a goal location from any point in the environment. Hill climbing in this dynamic-programming function yields paths with the shortest expected travel time. 13
From M. Montemerlo et al., Junior: The Stanford Entry in the Urban Challenge 14
Examples of Components of Stanley / Junior Unstructured navigation (e.g., parking lots, u-turns) Junior used a fast, modified version of the A* algorithm. This algorithm searches shortest paths relative to the vehicle s map, using search trees. 15
From M. Montemerlo et al., Junior: The Stanford Entry in the Urban Challenge 16
Examples of Components of Stanley / Junior 17
18
New York Times: Google lobbies Nevada to allow self-driving cars http://www.nytimes.com/2011/05/11/science/11drive.html 19
Sociable Robotics 20
Kismet Kismet and Rich 21
What can Kismet do? 22
What can Kismet do? Vision Visual attention Speech recognition (emotional tone) Speech production (prosody) Speech turn-taking Head and face movements Facial expression Keeping appropriate personal space 23
Overview and Hardware 24
Expressions examples 25
From Recognition of Affective Communicative Intent in Robot-Directed Speech C. BREAZEAL AND L. ARYANANDA Perceiving affective intent 26
From Recognition of Affective Communicative Intent in Robot-Directed Speech C. BREAZEAL AND L. ARYANANDA Perceiving affective intent 27
Perceiving affective intent 28
From A context-dependent attention system for a social robot C. Breazeal and B. Scassellati Vision system 29
From people.csail.mit.edu/paulfitz/present/social-constraints.ppt External influences on attention Weighted by behavioral relevance Current input Skin tone Color Motion Habituation Pre-attentive filters Saliency map Attention is allocated according to salience Salience can be manipulated by shaking an object, bringing it closer, moving it in front of the robot s current locus of attention, object choice, hiding distractors,
Vision System: Attention 31
From people.csail.mit.edu/paulfitz/present/social-constraints.ppt Internal influences on attention Seek toy low skin gain, high saturated-color gain Looking time 28% face, 72% block Seek face high skin gain, low color saliency gain Looking time 28% face, 72% block Internal influences bias how salience is measured The robot is not a slave to its environment
Attention: Gaze direction 33
Attention System 34
From people.csail.mit.edu/paulfitz/present/social-constraints.ppt Negotiating interpersonal distance Person backs off Person draws closer Too close withdrawal response Comfortable interaction distance Too far calling behavior Beyond sensor range Robot establishes a personal space through expressive cues Tunes interaction to suit its vision capabilities
Negotiating personal space 36
From people.csail.mit.edu/paulfitz/present/social-constraints.ppt Negotiating object showing Comfortable interaction speed Too fast, Too close threat response Too fast irritation response Robot conveys preferences about how objects are presented to it through irritation, threat responses Again, tunes interaction to suit its limited vision Also serves protective role
Negotiating object showing 38
Adapted from people.csail.mit.edu/paulfitz/present/social-constraints.ppt Turn-Taking Cornerstone of human-style communication, learning, and instruction Phases of turn cycle Listen to speaker: hold eye contact Reacquire floor: break eye contact and/or lean back a bit Speak: vocalize Hold the floor: look to the side Stop one s speaking turn: stop vocalizing and re-establish eye contact Relinquish floor: raise brows and lean forward a bit
Conversational turn-taking
Web page for all these videos: http://www.ai.mit.edu/projects/sociable/videos.html 41
How to evaluate Kismet? What are some applications for Kismet and its descendants? 42
Leonardo http://www.youtube.com/watch?v=ilmdn2e_flc 43