In a large scale real time control system, functions of subsystems differ slightly although they seem to be identical. Functions change when hardware is replaced or when the function itself is upgraded. If the standard system is generated by merging the differences and is installed then to each subsystem, subsystems become different with maintenance being carried out in each subsystem to fit its operational conditions. Furthermore, subsystems are distributed in a wide area. Software maintenance therefore becomes very difficult. The paper describes a distributed management for software maintenance in the Tokyo metropolitan area railway system. This management has two phases: generating programs for making maintenance easy and executing programs for increasing the reliability of the system. There it contributes to the effectiveness of maintenance and increases the reliability of the total system.

The design and analysis of a high-speed insertion hand, the dynamic RCC hand, are presented. The dynamic behavior of a peg in high-speed insertion is analyzed. Conditions for the peg to be guided along the chamfer without bouncing on the surface are derived. Mass properties of the peg and its supporting mechanism that enable successful insertion are determined. A high-speed insertion hand is designed on the basis of the dynamic analysis. Experiments demonstrate the feasibility and usefulness of the dynamic insertion hand.>