Page 17 - Introduction to Autonomous Mobile Robots

Chapter 1
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on where it is bolted down. In contrast, a mobile robot would be able to travel throughout
the manufacturing plant, flexibly applying its talents wherever it is most effective.
This book focuses on the technology of mobility: how can a mobile robot move unsu-
pervised through real-world environments to fulfill its tasks? The first challenge is locomo-
tion itself. How should a mobile robot move, and what is it about a particular locomotion
mechanism that makes it superior to alternative locomotion mechanisms?
Hostile environments such as Mars trigger even more unusual locomotion mechanisms
(figure 1.2). In dangerous and inhospitable environments, even on Earth, such teleoperated
systems have gained popularity (figures 1.3, 1.4, 1.5, 1.6). In these cases, the low-level
complexities of the robot often make it impossible for a human operator to directly control
its motions. The human performs localization and cognition activities, but relies on the
robot’s control scheme to provide motion control.
For example, Plustech’s walking robot provides automatic leg coordination while the
human operator chooses an overall direction of travel (figure 1.3). Figure 1.6 depicts an
underwater vehicle that controls six propellers to autonomously stabilize the robot subma-
rine in spite of underwater turbulence and water currents while the operator chooses posi-
tion goals for the submarine to achieve.
Other commercial robots operate not where humans cannot go but rather share space
with humans in human environments (figure 1.7). These robots are compelling not for rea-
sons of mobility but because of their autonomy, and so their ability to maintain a sense of
position and to navigate without human intervention is paramount.

Figure 1.2
The mobile robot Sojourner was used during the Pathfinder mission to explore Mars in summer 1997.
It was almost completely teleoperated from Earth. However, some on-board sensors allowed for
obstacle detection. (http://ranier.oact.hq.nasa.gov/telerobotics_page/telerobotics.shtm).
© NASA/JPL