Takeiki Aizono

Autonomous decentralized software structure for integration of information and control systems

A new software structure for integrating information and control systems has been developed. In conventional manufacturing systems, these two kinds of systems are separated and connected by gateways in a hierarchical structure. Both systems need to be integrated, however, in order to increase productivity and to enable the systems to be modified frequently. Timely production and frequent rescheduling of production are required in order to meet rapid changes in customer demands. These integrated systems must also be expandable and flexible. The differences of properties between information and control systems had made it impossible to integrate these systems, so an autonomous decentralized software structure implemented using three new technologies is proposed. These technologies are a timer trigger mechanism that manages the triggering of different kinds of information and control application programs, an interface management mechanism that manages different kinds of data received by these programs, and a message filtering mechanism that segregates the messages transmitted among heterogeneous applications and thus prevents the different applications from interrupting each others operations. This new software structure has been applied to manufacturing systems, and the effectiveness of the proposed technologies has been confirmed.

The development of security system and visual service support software for on-line diagnostics

Hitachis CD-SEM achieves the highest tool availability in the industry. However, efforts to further our performance are continuously underway. The proposed on-line diagnostics system can allow senior technical staff to monitor and investigate tool status by connecting the equipment supplier and the device manufacturer sites through the Internet. The advanced security system ensures confidentiality by firewalls, digital certification, and advanced encryption algorithms to protect device manufacturer data from unauthorized access. Service support software, called DDS (defective part diagnosis support system), will analyze the status of mechanical, evacuation, and optical systems. Its advanced overlay function on a timing chart identifies failed components in the tool and allows on-site or remote personnel to predict potential failures prior to their occurrence. Examples of application shows that the proposed system is expected to reduce repair time, improve availability and lower cost of ownership.

A QoS Management Technique of Urgent Information Provision in ITS Services Using DSRC for Autonomous Base Stations

A QoS management technique based on an autonomous decentralized mobility system, which is an autonomous decentralized system enhanced to provide mobile stations with information about urgent roadway situations, is proposed in this paper. This technique enables urgent messages to be flexibly and quickly transmitted to mobile stations by multiple decentralized base stations using dedicated short range communication. It also supports the easy addition of additional base stations. Each station autonomously creates information-delivery communities based on the urgency of the messages it receives through the roadside network and the distances between the senders and receivers. Each station dynamically determines the urgency of messages according to the message content and the speed of the mobile stations. Evaluation of this technique applied to the Smart Gateway system, which provides driving-assistance services to mobile stations through dedicated short-range communication, demonstrated its effectiveness and that it is suitable for actual systems.

A proposal of Quality of Service (QoS) control method to realize highly-reliable communications for roadside system

In this study, we consider a chained computing system - a system that includes a large number of base stations, each with a very narrow communication area, that cooperatively deliver various services to mobile terminals in vehicles moving, at high speed. In operation, several autonomous base stations dynamically form themselves into a group on the basis of a service scenario received from a mobile terminal and profiles that describe the characteristics and the capabilities of each autonomous base station and autonomously deliver different kinds of services to the mobile terminal. First, we explain the basic model of a chained computing system and describe high-assurance, high-performance, and high-quality architectures that can be used for service delivery to a mobile terminal moving at high speed. Second, we discuss a Quality of Service (QoS) control method applied through these architectures to the roadside system, which is a component of the smart gateway system proposed by the Telecommunication Advancement Organization of Japan (TAO). We also discuss evaluation results concerning the QoS control method.

Modularized system architecture for flexible clinical laboratory systems

The increase in medical expenses resulting from longer life expectancy is an increasing serious social problem in Japan. Reducing the cost of clinical laboratory systems, increasing quality of service to patients, and safeguarding the health of hospital staff are important issues for hospitals. A flexible clinical laboratory system is needed to reduce system development cost. Automated clinical laboratory systems, for large and small hospitals alike, are needed in order to reduce waiting time and the risk of workers being exposed to infectious diseases. Flexible systems could meet all these needs. We have developed a modularized system architecture to provide a flexible clinical laboratory system. The hardware and software of the clinical and sample transfer equipment are modularized in this system. Each piece of equipment can autonomously decide where to transfer samples and how to process them. The clinical equipment works autonomously and can be added or suspended without influencing the other equipment. The transfer equipment is also autonomous, and the sample transfer lines can be changed easily in accordance with space limitations. We applied this modularized system architecture to a pre-analytical sample-handling system, and demonstrated its effectiveness. This system was developed by using equipment from different vendors, thus demonstrating that such a system can be easily built.

Intelligent scheduling based on start time adjustment for advanced sequential control systems

High productivity is required for industrial systems that are to produce large amounts of low-price products. Most industrial systems are sequentially controlled because materials and parts are processed and constructed step by step. A new method of sequential control is needed to increase productivity, and a new technique to schedule the start time of each process is also needed because of frequent adjustment of production lines and their equipment. Intelligent devices such as intelligent sensors and actuators used in the latest industrial systems have embedded high-performance processors and contain software modules. These devices cooperate and control processing robots and production lines. Advanced sequential control is proposed for sequential control systems consisting of distributed software modules. Processing time can be minimized and productivity increased by intelligent scheduling for advanced sequential control, and this paper describes a new method for adjusting the starting times of production processes automatically. This method shortens the time margin and decreases the total processing time. This paper also describes a processing flow diagram that makes it easy to adjust the starting time of each process. The effectiveness of this intelligent scheduling and start-time-adjustment has been demonstrated by using them to optimize the operation of a system for testing disk plates.

Development of on-line diagnosis system using intelligent devices for semiconductor equipment

To enable safe, profitable LSI manufacture, semiconductor equipment must be reliable. Equipment failure can cause serious problems, such as an explosion in the chamber, which can stop the fabrication line for a long time. Such problems arise because potential equipment failure cannot be detected in advance. To remedy this, we have developed an on-line detection system that incorporates intelligent devices, such as sensors and actuators, the CPU and communication interface of which enable on-line self-diagnosis.

An object model of autonomous control processor and the message selection method

This paper describes new fault-tolerant technology using a simple object-based Autonomous Decentralized System (ADS) model. Recent advances in processor technology have made it possible to connect not only computers but also devices to networks resulting in an increasing number of nodes in a system. Control logic of a computer or a controller has become widely, distributed among a huge number of devices, such as sensors and actuators. More flexible and lower cost systems are required because of the downsizing of control systems. In order to achieve these requirements, the Structured Autonomous Control Processor (SACP) model and a message selection method has been proposed. This model and method show how scalable fault-tolerance and increased maintainability of device-level distributed computing systems can be achieved. SACP and the message selection method are applied to a SACP chip and the effectiveness has been verified. Some SACP functions have become the de facto standard for communication protocol used in manufacturing systems and have started to be used worldwide.