伐倒ポータブルマニピュレータ巽TATSUMIの開発

抄録

This paper presents a portable tree felling manipulator which has never been developed so far in Japan. A man-made forest is in an urgent need for logging. Furthermore, many fatal accidents and severe injuries occur during tree felling operations. These accidents are mainly due to cutting inaccuracies, with respect to falling directions of downed trees, of chainsaws operated by humans. And Japan's forests are precipitous, wet, humid and soft terrain, with great temperature fluctuations and a low logging road density. The device must withstand such environmental conditions. Based on these authors' research results, a set of design requirements is established. The manipulator must be as simple as possible as a mechanical apparatus so that operators may conduct maintenance and repair work themselves. And the manipulator must be small and light for one person to carry. And for reaching the stage of practical use, it is equipped with an engine chainsaw commonly used throughout logging sites. And then the prototypes that embodied ultimate simplicity in its shape and mechanism were devised. The authors developed the manipulator composed of 4 degrees of freedom required minimum. To operate the manipulator, and they also developed a control system with a software program that converts rotational motions of the manipulator joints into linear sawing motions. A demonstrative model was built, experimented on, evaluated for its performance using standard evaluation methods adopted by the forestry industry, and verified to be effective. The results of experiments clearly explain that the safety of the felling operation by the proposed manipulator was successfully demonstrated.