Technology Development for Army Unmanned Ground Vehicles (2002) / Chapter Skim
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Appendix D: Historical Perspective
Appendix D: Historical Perspective
Pages 151-160
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From page 151... ...
Using a modified Cart, he obtained stereo images by moving a black and white video camera side to side to create a stereo baseline. Like Shakey, Moravec' s Cart operated mostly indoors in a room with simple polygonal objects, painted in contrasting black and white, uniformly lit, with two or three objects spaced over 20 meters.
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From page 152... ...
, stereo remained computationally prohibitive and the range finders of the time, which required much less computation, were too slow.6 THE ALV ERA 1984-1991 In 1983, DARPA started an ambitious computer research program, the Strategic Computing program. The pro40ne of the fundamental steps in image understanding is to segment or partition a scene into a set of regions, each of which is homogeneous with respect to a set of properties that correspond to semantically meaningful entities in the scene.
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From page 153... ...
This worked well for relatively flat roads but was inadequate in open terrain, where assumptions about the location of the ground plane were more likely to be in error. Work on road following continued, experimenting with algorithms primarily from Carnegie Mellon University (CMU)
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From page 154... ...
The reactive paradigm was a response to the difficulties in machine vision and in planning that caused robots to operate slowly. Brooks reasoned that insects and some small animals did very well without much sensor data processing or planning.
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From page 155... ...
Up to that time the standard wisdom in the computer vision community was that area-based algorithms were too slow and too unreliable for real-time operation; most work up to that point had used edge detection, which gave relatively sparse depth maps not i3Neural networks are function approximators, creating a mapping from input features to output. There are many other approaches that can be used.
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From page 156... ...
The Demo II vehicles (see Figure D-3) were HMMWVs equipped with stereo black-and-white video cameras on a fixed mount for obstacle avoidance, and a single color camera on a pan-and-tilt mount for the road following.
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From page 157... ...
Stereo vision was used in Demo I for obstacle detection at up to 10 mph. Demo II added obstacle avoidance off-board demonstrations of night stereovision with 3-5,um FLIR, and increased the speed and resolution of the system to 256 x 80 pixel range images at the 1.4-Hz frame rate.
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From page 158... ...
IMU, GPS, odometry NCD Limited: neural network for road following Note: ALV = autonomous land vehicle; NCD = no capacity demonstrated; FLIR = forward looking infrared radar; DRP = dynamic route planning; ROM = read-only memory; SLOC = source lines of code; LADAR = laser detection and ranging; IMU = inertial measurement unit, GPS = global positioning system.
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From page 159... ...
Reconnaissance, Surveillance, and Target Acquisition for the Unmanned Ground Vehicle: Providing Surveillance "Eyes" for an Autonomous Vehicle. San Francisco, Calif.: Morgan Kaufmann Publishers.
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From page 160... ...
1986. Road following by an autonomous vehicle using range data.
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