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specific task another controller needs to manage some low level skills like running,
turning, jumping and so on, which are necessary to ensure the realization of the high level
task [142, 143, 154, 155]. Therefore, by understanding some robot properties the high
level task management is very simple in the high level controller. In the above referenced
evaluation, authors have tried to find lateral undulation locomotion for a snake robot. Each
hinge has two degree of freedom (2-DOF) and can turn in 2 directions. With the method
based on genetic algorithms, an optimum template is obtained to make the robot moving
or acting according to our desires. The most important point in this learning method is that
we don’t predefine any robot kinematics for movement/locomotion in the fitness function.
The fitness function is a simple and important function which defines the robot behavior in
the environment. Complicated rules and equations in the fitness function cannot improve
the robot behavioral performance; a simple definition can result to a best robot behavior.
Equation 9-2, define the fitness function used for the snake robot lateral undulation
locomotion shown in Figure 9-6.
(9-2.a)
(9-2.b)
(9-2.c)
(9-2.d)
The term
‘AVG’
denotes the mean distances between parts and the
‘x’
axis. The term
‘L
i
’
denotes the distance between the
i’th
