CS 287: Advanced Robotics
Fall 2009
                    Lecture 1: Introduction
                        Pieter Abbeel
                      UC Berkeley EECS
www
   http://www.cs.berkeley.edu/~pabbeel/cs287-fa09
   Instructor: Pieter Abbeel
   Lectures: Tuesdays and Thursdays, 12:30pm-2:00pm,
    405 Soda Hall
   Office Hours: Thursdays 2:00-3:00pm, and by email
    arrangement. In 746 Sutardja Dai Hall
                           Page 1
Announcements
   Communication:
        Announcements: webpage
        Email: pabbeel@cs.berkeley.edu
        Office hours: Thursday 2-3pm + by email
         arrangement, 746 SDH
   Enrollment:
        Undergrads stay after lecture and see me
Class Details
   Prerequisites:
        Familiarity with mathematical proofs, probability, algorithms,
         linear algebra, calculus.
        Ability to implement algorithmic ideas in code.
        Strong interest in robotics
   Work and grading
        Four large assignments (4 * 15%)
        One smaller assignment (5%)
        Open-ended final project (35%)
   Collaboration policy: Students may discuss assignments with each
    other. However, each student must code up their solutions
    independently and write down their answers independently.
                                 Page 2
Class Goals
   Learn the issues and techniques underneath state of the
    art robotic systems
   Build and experiment with some of the prevalent
    algorithms
   Be able to understand research papers in the field
       Main conferences: ICRA, IROS, RSS, ISER, ISRR
       Main journals: IJRR, T-RO, Autonomous Robots
   Try out some ideas / extensions of your own
Lecture outline
   Logistics --- questions? [textbook slide forthcoming]
   A few sample robotic success stories
   Outline of topics to be covered
                          Page 3
    Driverless cars
       Darpa Grand Challenge
           First long-distance driverless car competition
           2004: CMU vehicle drove 7.36 out of 150 miles
           2005: 5 teams finished, Stanford team won
       Darpa Urban Challenge (2007)
           Urban environment: other vehicles present
           6 teams finished (CMU won)
       Ernst Dickmanns / Mercedes Benz: autonomous car on European
        highways
           Human in car for interventions
           Paris highway and 1758km trip Munich -> Odense, lane
            changes at up to 140km/h; longest autonomous stretch: 158km
 Kalman filtering, Lyapunov, LQR, mapping, (terrain & object recognition)
    Autonomous Helicopter Flight
                                                             [Coates, Abbeel & Ng]
Kalman filtering, model-predictive control, LQR, system ID, trajectory learning
                                   Page 4
   Four-legged locomotion
                                                          [Kolter, Abbeel & Ng]
inverse reinforcement learning, hierarchical RL, value iteration, receding
horizon control, motion planning
   Two-legged locomotion
                                                          [Tedrake +al.]
TD learning, policy search, Poincare map, stability
                                 Page 5
   Mapping                             [Video from W. Burgard and D. Haehnel]
“baseline” : Raw odometry data + laser range finder scans
   Mapping                             [Video from W. Burgard and D. Haehnel]
FastSLAM: particle filter + occupancy grid mapping
                                Page 6
     Mobile Manipulation
                     [Quigley, Gould, Saxena, Ng + al.]
SLAM, localization, motion planning for navigation and grasping, grasp point
selection, (visual category recognition, speech recognition and synthesis)
     Outline of Topics
    Control: underactuation, controllability, Lyapunov, dynamic
     programming, LQR, feedback linearization, MPC
    Estimation: Bayes filters, KF, EKF, UKF, particle filter, occupancy
     grid mapping, EKF slam, GraphSLAM, SEIF, FastSLAM
    Manipulation and grasping: force closure, grasp point selection,
     visual servo-ing, more sub-topics tbd
    Reinforcement learning: value iteration, policy iteration, linear
     programming, Q learning, TD, value function approximation, Sarsa,
     LSTD, LSPI, policy gradient, inverse reinforcement learning, reward
     shaping, hierarchical reinforcement learning, inference based
     methods, exploration vs. exploitation
    Brief coverage of: system identification, simulation, pomdps, k-
     armed bandits, separation principle
    Case studies: autonomous helicopter, Darpa Grand/Urban
     Challenge, walking, mobile manipulation.
                                 Page 7
1. Control
   Overarching theme: mathematically capture
       What makes control problems hard
       What techniques do we have available to tackle the
        hard problems
   E.g.: “Helicopters have underactuated, non-minimum
    phase, highly non-linear and stochastic (within our
    modeling capabilities) dynamics.”
          Hard or easy to control?
1. Control (ctd)
   Under-actuated vs. fully actuated
       Example: acrobot swing-up and balance task
                          Page 8
1. Control (ctd)
   Other mathematical formalizations of what makes some
    control problems easy/hard:
        Linear vs. non-linear
        Minimum-phase vs. non-minimum phase
        Deterministic vs. stochastic
   Solution and proof techniques we will study:
        Lyapunov, dynamic programming, LQR, feedback
         linearization, MPC
2. Estimation
   Bayes filters: KF, EKF, UKF, particle filter
   One of the key estimation problems in robotics:
    Simultaneous Localization And Mapping (SLAM)
   Essence: compute posterior over robot pose(s) and
    environment map given
        (i) Sensor model
        (ii) Robot motion model
   Challenge: Computationally impractical to compute
    exact posterior because this is a very high-dimensional
    distribution to represent
   [You will benefit from 281A for this part of the course.]
                                       Page 9
3. Grasping and Manipulation
   Extensive mathematical theory on grasping: force
    closure, types of contact, robustness of grasp
   Empirical studies showcasing the relatively small
    vocabulary of grasps being used by humans (compared
    to the number of degrees of freedom in the human
    hand)
   Perception: grasp point detection
4. Reinforcement learning
   Learning to act, often in discrete state spaces
   value iteration, policy iteration, linear programming, Q
    learning, TD, value function approximation, Sarsa,
    LSTD, LSPI, policy gradient, inverse reinforcement
    learning, reward shaping, hierarchical reinforcement
    learning, inference based methods, exploration vs.
    exploitation
                          Page 10
5. Misc. Topics
   system identification: frequency domain vs. time domain
   Simulation / FEM
   Pomdps
   k-armed bandits
   separation principle
   …
Reading materials
   Control
        Tedrake lecture notes 6.832:
         https://svn.csail.mit.edu/russt_public/6.832/underactuated.pdf
   Estimation
        Probabilistic Robotics, Thrun, Burgard and Fox.
   Manipulation and grasping
        -
   Reinforcement learning
        Sutton and Barto, Reinforcement Learning (free online)
   Misc. topics
        -
                               Page 11
   Next lecture we will start with our study of control!
                          Page 12