Hitoshi Hashizume

X-Y-θ Nano-Positioning Table System for a Mother Machine

Abstract Within recent manufacturing environment, there is an increasing demand for nanometer positioning table system with high stiffness, high resolution and high repeatability. In this study, therefore, a high-stiffness X-Y-6 nano-positioning table system has been developed for ultraprecision machine tools. The table is levitated by high-stiffness aerostatic bearings with porous material and driven by six voice coil motors in a non-contact condition. The table system is designed symmetrically about the driving axis and consequently free from nonlinear behavior and direction dependency. The performance of the developed table system has been verified through a series of nano-positioning experiments.

Nanometer Positioning of a Linear Motor-Driven Ultraprecision Aerostatic Table System with Electrorheological Fluid Dampers

Abstract With the ever increasing demand for higher accuracy and higher productivity in the world-wide manufacturing environment, ultraprecision table positioning technology is urgently required. In order to establish an ultraprecision technology of nanometer accuracy capability, it is important to develop ultraprecision table systems based on new design concepts. In this study, therefore, a linear motor-driven ultraprecision aerostatic table system equipped with electrorheologicai fluid dampers is described, with proven nanometer positioning accuracy.

Sensor-less Monitoring of Cutting Force during Ultraprecision Machining

Abstract Future ultraprecision machining systems will require intelligent machine tools equipped with effective systems for in-process monitoring of maching status. To meet the requirement, much attention has been directed to the monitoring method of cutting force, temperature, acoustic emission, etc. Cutting force includes useful information on machining status, however, it is difficult to apply these methods for an ultraprecision maching environment. In this paper, a sensor-less monitoring method has been proposed based on a new concept. In the proposed method, a disturbance observer is installed In the position controller for a liner motor-driven aerostatic table system. The performance of the monitoring system has been evaluated through a series of ultraprecision machining experiments.

High Speed Nanometer Positioning Using a Hybrid Linear Motor

Abstract With ever increasing demand for higher accuracy and productivity, high speed ultraprecision table positioning technology is urgently required. In order to achieve nanometer positioning accuracy and high speed feed drive of the table, it is effective to minimize error factors in the table system by using a linear motor in perfect noncontact condition. In such a linear motor-driven table system of a noncontact type, however, the force ripple of the motor directly influences the linear motion error of the table. In this study, a hybrid linear motor has been developed which has no force ripple. The proposed hybrid linear motor is constructed from a voice coil motor and a coarse driving mechanism, e.g., a wire drive. Furthermore, a hybrid linear motor-driven aerostatic table system has been developed and the performance of the table system has been evaluated.

Structural Configuration and Performances of Machining Environment-Controlled Ultraprecision Diamond Turning Machine "Capsule"

To establish a future ultra-precision machining technology of nano-meter order, it is important to realize the machine tool structure based on a new design concept. Therefore, A Machining Environment-Controlled Ultra-Precision Diamond Turning Machine has been newly developed. This machine can be characterized by its capsule-like closed structure along with various new mechanisms. The machine aims especially at the manufacture of the high precision mirror under various environments. At present, the flat mirror with 3nm in surface roughness (Al-alloy) is in reality.

In-Process Monitoring Method for Machining Environment Based on Simultaneous Multiphenomena Sensing

Abstract The successful implementation of intelligent manufacturing systems requires in-process monitoring of the machining environment. The monitoring system should be capable of extracting multifaceted information about the environment. However, most current systems are based on single phenomenon monitoring, so their effectiveness is quite limited. In this paper, a new multifunctional in-process monitoring method has been proposed. This method, based on simultaneous multiphenomena sensing, can monitor multidimensional responses simultaneously. Through experiment and simulation, it has been verified that the method is effective and applicable to monitoring in a machining environment.

Structured Method for Identifying Success Factors in New Product Development of Machine Tools

Abstract New product development of machine tools is always costly and risky for machine tools manufacturers; nevertheless, there have been few academic studies on the product development process of machine tools. Successful product developments were found to be related to perceived superior skills and resources within the objective of machine tools manufacturers. In this study, in order to establish the product development methodology for machine tools, the success factors in new product development have been identified based on the results of the interview and questionnaire investigations with experienced engineers in Japanese machine tools manufacturers. Based on the findings of this study, a structured method for identifying the success factors in new product development has been proposed.

Product Development Methodology for Machine Tools. Usability Analysis of Man-Machine Interface.

To establish a new product development methodology for machine tools, it is necessary and indispensable to analyze usability of man-machine interface for machine tools and also to systematize the design procedures of a control panel of CNC controller. However, the man-machine interface of machine tools has not been investigated yet. In this study, therefore, a concept of usability has been defined based on the results of interview investigations with some mature operators and a method for analyzing usability of man-machine interface for machine tools has been proposed. Furthemore, it has been verified that the proposed analyzing method for man-machine interface has an effective means to design and realize a desirable control panel of CNC controller for machine tools.