Transcript Just Add Wheels: Leveraging Commodity Laptop Hardware for Robotics Education Jonathan Kelly, Jonathan Binney, Arvind Pereira, Omair Khan and Gaurav S.

Just Add Wheels:
Leveraging Commodity
Laptop Hardware for
Robotics Education
Jonathan Kelly, Jonathan Binney, Arvind Pereira,
Omair Khan and Gaurav S. Sukhatme
Robotic Embedded Systems Laboratory
Department of Computer Science
University of Southern California
Sunday, July 13, 2008
Introduction
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We propose using commodity laptop hardware
for robotics education.
We motivate the approach by discussing
relevant studies and statistics.
We then describe our prototype laptop robot,
including software based on the open source
Player-Stage package.
We present results from monocular SLAM and
bump detection experiments, using laptop
sensors.
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Talk Outline
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Introduction
Motivation
Leveraging Laptop Hardware for Education
The “LapBot”, a Prototype Laptop Robot
Monocular SLAM
Bump Sensing
Conclusions and Future Work
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Motivation
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Robotics projects are fun and exciting –
excellent for learning about physics, math,
computer science etc.
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Can be used to motivate students who may not
otherwise choose to pursue Science or Engineering
(Blank 2006).
Numerous barriers to widespread adoption of
robotics curriculum, however, at both college
and K-12 levels.
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Include lack of teacher training, suitable educational
resources, and affordable robot platforms (Mataric et al.
2007).
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Leveraging Laptop Hardware
• How can we both interest students in robotics,
and get them involved at reasonably low cost?
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Need mobility, sensor and software components.
Idea: Leverage sensors and computing power
inside the laptops that they already own.
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2007 ECAR survey: 73.7% of college students now
own laptops.
Cameras already available in many models,
accelerometers on some (Acer, Apple, IBM).
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Our Approach
1. Explore the idea of using student-owned
laptops as capable robot platforms.
2. Use on-board hardware (e.g. camera,
accelerometer etc.) for sensing and
computing.
3. “Just add wheels”, i.e. a motorized base, for
mobility.
4. Develop an open source software platform,
freely available, to take advantage of this
hardware.
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The LapBot
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Prototype hardware / software platform.
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Apple MacBook Core Duo laptop
iRobot Create mobile base
Runs (free) Ubuntu Linux.
Software for two tasks:
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Monocular SLAM using the
built-in iSight camera.
Bump sensing / obstacle
detection using accelerometer.
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System Block Diagram
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MonoSLAM
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We use a freely-available monocular (singlecamera) SLAM package (Davison 2003).
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Full 6-DoF SLAM running in real time.
Requires initialization using known calibration target.
Image data is acquired from internal iSight
camera.
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Grabs frames on the MacBook Core Duo at 5 – 10
Hz.
640 x 480 VGA resolution.
Works qualitatively very well.
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MonoSLAM Example
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Bump Sensing
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Access the on-board Apple Sudden Motion
Sensor.
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High-resolution, high-speed three-axis solid-state
accelerometer unit.
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250 counts per gravity. Sampled at more than 300 Hz.
No official API from Apple (yet), but reading data is
easy.
Repurpose the sensor for bump/collision
detection.
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Threshold test on smoothed sensor output. > 0.4 g’s
is a considered a bump.
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Bump Sensing Example
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The LapBot in Action
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Video shows student
driving the LapBot
manually in our lab
building.
Display support
holds screen (and
camera) rigidly
upright – this aides
feature tracking.
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Conclusions
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Described and motivated the design of a
prototype laptop robot built to leverage
hardware that is likely available (or will be
available) to students.
Both MonoSLAM and accelerometer-based
bump sensing work well, and run in real-time
on laptop processor.
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One of the benefits of using a full laptop instead of an
embedded processor.
Emphasize that all hardware except for
locomotion is built into the laptop itself.
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Future Work
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Continuing to develop out-of-the-box software
packages for a variety of laptop hardware.
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User should be able to install with minimal effort, i.e.
the package has to ‘just work’.
Trial in a classroom environment.
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Presently, we have a simple proof-of-concept
implementation.
Need to carefully evaluate the feasibility of the
approach
for a real classroom.
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Ideally, this would be a freshman college class. K-12
would come later.
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Thank You.
Questions?
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