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Introduction to Biologically Inspired Robotics
1.3 Biologically Inspired Robot Design
Designing mechanisms for robots that mimic the motion of animals and
other living creatures is one of the core problems in biologically inspired
robotics. The mechanisms of movement vary for different animals and other
living creatures. Many mammals, such as cats, tigers, horses, etc., use four
legs to move around, but humans rely on two legs to move. Spiders use legs
to climb, but snakes climb without legs. The challenging issue here is how to
realize biological movement using mechanical structures. Biological motion
is generated by the interaction of muscles, joints, and tissues of a continuum
deformable body. There are no actuators that are as sophisticated as muscles,
materials that are as soft as tissues, or joints that generate the complicated
yet smooth motion that human and animal joints perform. Therefore, it is
crucial to develop simplified mechanisms that can generate motion similar
to biological motion.
For example, a snake moves forward and backward using the frictional
force between its body and the ground. Its body is a deformable continuum
whose geometric shape is used to control the frictional force. The snake can
change its speed by changing the shape of its body. Because it is difficult
to design a mechanical structure that can deform freely and continuously
by active control, existing robotic snakes employ a series of movable segments that are connected by a joint (Figure 1.5). Moreover, the snake relies
on its skin to slide on the ground, and such skin cannot be made by current
technologies, so wheels are attached to the segments. If the connection joint
allows the rotation about one axis, the robotic snake moves in a plane. If
the connection joint is a spherical joint that allows rotation about two perpendicular axes, the robotic snake can move in three-dimensional space; for
example, to climb a tree.
By observing the motion of animals and insects, researchers have designed
legged robots including biped or humanoid robots, four-legged robots that
mimic the mechanisms of animal movement, and robots with eight, twelve,
or even more legs. Legged robots move by repeatedly lifting and moving
their legs backward or forward as animals do. Figure 1.6 shows a four-legged
and a six-legged mobile robot. Other examples of biomimetic robots include
the robotic fish developed at the University of Essex (see Figure 1.4).
1.4 Biologically Inspired Robot Control
The behaviors of animals and other living creatures inspire the development
of new ideas for controlling the motion or behaviors of robots. In principle,
robotic control and biological control systems are similar. They all work
Introduction to Biologically Inspired Robotics
1.3 Biologically Inspired Robot Design
Designing mechanisms for robots that mimic the motion of animals and
other living creatures is one of the core problems in biologically inspired
robotics. The mechanisms of movement vary for different animals and other
living creatures. Many mammals, such as cats, tigers, horses, etc., use four
legs to move around, but humans rely on two legs to move. Spiders use legs
to climb, but snakes climb without legs. The challenging issue here is how to
realize biological movement using mechanical structures. Biological motion
is generated by the interaction of muscles, joints, and tissues of a continuum
deformable body. There are no actuators that are as sophisticated as muscles,
materials that are as soft as tissues, or joints that generate the complicated
yet smooth motion that human and animal joints perform. Therefore, it is
crucial to develop simplified mechanisms that can generate motion similar
to biological motion.
For example, a snake moves forward and backward using the frictional
force between its body and the ground. Its body is a deformable continuum
whose geometric shape is used to control the frictional force. The snake can
change its speed by changing the shape of its body. Because it is difficult
to design a mechanical structure that can deform freely and continuously
by active control, existing robotic snakes employ a series of movable segments that are connected by a joint (Figure 1.5). Moreover, the snake relies
on its skin to slide on the ground, and such skin cannot be made by current
technologies, so wheels are attached to the segments. If the connection joint
allows the rotation about one axis, the robotic snake moves in a plane. If
the connection joint is a spherical joint that allows rotation about two perpendicular axes, the robotic snake can move in three-dimensional space; for
example, to climb a tree.
By observing the motion of animals and insects, researchers have designed
legged robots including biped or humanoid robots, four-legged robots that
mimic the mechanisms of animal movement, and robots with eight, twelve,
or even more legs. Legged robots move by repeatedly lifting and moving
their legs backward or forward as animals do. Figure 1.6 shows a four-legged
and a six-legged mobile robot. Other examples of biomimetic robots include
the robotic fish developed at the University of Essex (see Figure 1.4).
1.4 Biologically Inspired Robot Control
The behaviors of animals and other living creatures inspire the development
of new ideas for controlling the motion or behaviors of robots. In principle,
robotic control and biological control systems are similar. They all work