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Ch05-I044963.fm Page 21 Tuesday, August 1, 2006 5:42 PM
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Tuesday, August
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A picture taken by a CCD camera and binarized with an appropriate threshold level when illuminated
is shown in Fig. 7. Only marks are conspicuous and the image processing becomes drastically easy
compared with processing the raw image data. A robot can recognize the type of the tableware by
reading the barcode information. Also the robot can calculate the position of the tableware by utilizing
image data of four marks. By using four marks, the reliability of reading barcode is also improved.
Barcode 1^ 215 mm
mark

Figure 7: Binary image
Figure 6: Tableware of
this research
Figure 8: Robot hand

A finger of robot hand is not able to put into inside of the tableware. And, the size of tableware is
various. To solve these problems, a robot hand is developed as shown in Fig. 8. This hand is equipped
with a link mechanism, and the tip of a finger is bent automatically so as to be fitted to the object outer
shape. Owing to this mechanism, the robot hand can hold an object firmly with four contact points.

EXPERIMENT

The task of preparing rice by using the developed rice scoop for a robot is carried out. The situation of
this task is shown in Fig. 9. The contents of the task are following (l)-(5):
(1) The rice scoop is put into the rice in a rice cooker.
(2) The rice scoop is moved horizontally and the rice is scooped up.
(3) The rice is transported and positioned over the bowl.
(4) The rice scoop is turned upside down and the rice is filled into the bowl.
(5) The rice is roundly shaped by the shaping cup.
Cooked rice is fairly filled into a bowl as shown in Fig. (6). From this result, it is proved that this
method is effective for preparing the rice.

The task of setting tableware is carried out by the robot as shown in Fig. 10. The contents of the task
are following (l)-(6):
(1) At a kitchen, the robot takes a picture of the tableware and recognizes it.
(2) The robot grasps the tableware by the developed robot hand with link mechanism.
(3) The robot loads the tableware to a tray.
(4) The robot transports the tray to the table. Landmarks on ceiling are employed for localizing the
robot.
(5) The robot sets the tableware on the table.
(6) The robot pours bottled drinks to a cup.
Seeing the series of performed tasks shown in Fig. 10, it seems possible in future that the task of
setting a meal on the table is realized by applying RECS concept.

CONCLUSION
As a part of development of a welfare robot based on RECS concept, the task of setting a meal on the