Abstract
Ultimate goal of this study is making up CIM of painting process for large scale steel product. For the purpose of it, the study aims at obtaining the solution to the problem of trajectory accuracy caused by singularity, especially on the trajectory in which tool orientation is changing along the path. We have developed two solutions. One solution is simple way of accuracy evaluation of that kind of trajectory. This way of accuracy evaluation consists of two steps. First step is searching the necessary condition of singularity. Second step is estimating influence of singularity on the necessary condition. We can modify no guarantee trajectory which we have found out by this way. The other solution is trajectory control without wrist singularity, using the change of tool orientation. In this trajectory control, angle of No. 4 axis is fixed and change of tool orientation toward the direction of painting path is permitted. The experimental results show that we can obtain high speed painting without deterioration of accuracy by using this new trajectory.