Abstract
Green caterpillar type robots have been studied widely to clarify their motion patterns. These robots were also applied to inspection medical treatment robots, maintenane robots or exploration robots. However, the method of using a single movement pattern is not the best strategy from a viewpoint of the movement efficiency when the environment with a different diameter in a duct exists variously. In this study, we consider a semi-looper type robot whose motion pattern can adapt to the change of situation.