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this error is to a minimum value, the better the behavior is.

One of the characteristics of the method in this study is that the proposed design system operates the
behavioral criteria that evaluate behaviors and creating novel behaviors with the operated behavioral
criteria. Another characteristic of the method is that it can obtain novel behavioral criteria from novel
behaviors.

DEFINITION
When designing behavioral patterns for a robot, the designer focuses on the coordinates of the robot's
fingertip, the joint of its elbow, and the joint of its shoulder, and their angles; otherwise, M. An and T.
Taura (2003) suggested that the designer may only pay attention to behavioral criteria such as
'smoothly', 'quickly' and so forth, which describe the whole movement from the start point of the
movement to the goal point.

Definition of Behavioral Pattern
In this study, we have defined behavioral patterns as trajectories drawn by an effector of the robot .
Figure 1 shows the elements of the effector of the robot. The coordinates of a fingertip, a wrist and
an elbow are expressed as (x_fmger, y_fmger & z_finger), (x_wrist, y_wrist, & z_finger) and
(xelbow, y_elbow& zelbow), and the angles of motion areOfinger, 9wrist,9elbow, cpfinger, cpwrist,
cpelbow, Aflnger, Awrist, and Xelbow, respectively.

it, Y_wist, Z_ wrist)

(Xjnj.r, Y_fing,,, Z_fing,,)
(X_»lbow, Y_»lbow, Z_»lbow)
Figure 1: Robotic effector

Definition of Behavioral Criteria

In this study, behavioral criteria are defined as criteria for evaluating whether a robot performs
behaviors as what the robot is expected to do. The behavioral criteria are treated as mathematic forms
in this study. For example, equation 1 shows a behavioral criterion that is for evaluating whether the
robot fingertip reaches a target.
2 2 2
E, ={X-x T) +(Y -y T) +(Z-z T) =0 ( ] )
Here, T indicates the numbers of steps needed to reach the target, x r, .F? and z T are the coordinates of
the fingertip of the robot, and X, Y and Z are the coordinates of the target.

DESIGN SYSTEM
The design system is proposed as shown in Figure 2. In step 1, we let the system acquire several basic
behavioral criteria of evaluating a model behavioral pattern. In step 2, the system reproduces