An optimum path and posture planning for fixtureless assembly

A strategy is discussed for assembly path planning of parts to be assembled by two assembly robots in a working space. Path modeling based on the use of real and virtual vertices of male and female parts is introduced to represent the relative relationship of parts in assembled position. A new algorithm for assembly path planning of two parts is developed. An algorithm for optimum posture (position and orientation) for a two-arm fixtureless assembly in the working space is proposed. A performance index is introduced to describe both accurate assembly capability and manipulability in the working space. The two strategies are combined, and the two-arm fixtureless assembly is demonstrated graphically for two planar robots.