The line balancing problem of assembly processes is one decisive factor in designing an efficient assembly system. It is generally difficult to solve this problem only by using computer because it includes ambiguous and non-quantative factors. A better way of treating this problem is to clarify the respective roles of a man and a computer, and to use effectively the respective functions of them. This idea is fundamental in Computer Aided Manufacturing (CAM).
A method based on CAM is proposed in this paper to treat the line balancing problem and is named as Iterative Structural Modeling of Assembly Processes (ISMAP). ISMAP consists of two processes, one is the ISM program extracting a precedence relation among the work elements of assembly processes, and the other is the line balancing program which has generality of its own, although formulated by a simpler algorithm for mini-computer. ISMAP has been applied to an assembly line for the frames of motor cycles in this paper as a practical application. The result obtained shows that it is possible to balance the physical loads of the workers more evenly without decreasing the system efficiency of the assembly line.