Title: INT 96-02 - STATUS ON RESEARCH AND PRODUCTION PRACTICES IN
INDUSTRIAL MACHINERY AND MACHINE TOOLS INDUSTRY IN JAPAN

Type: International Document

Exposure: Public NSF

Org: INT

Date: 2/5/96

Delete: 2/5/97

Replaces: INT 96-02 from 1/23/97 and 1/25/96

The National Science Foundation\'s offices in Tokyo and in Paris
periodically report on developments abroad that are related to the
Foundation\'s mission. These documents present facts for the use of NSF
program managers and policy makers; they are not statements of NSF
policy.

Report Memorandum #96-1 January 19, 1996

Status on Research and Production Practices in Industrial

Machinery and Machine Tools Industry in Japan

This report was written by Dr. Jay Lee, Program Director in NSF\'s
Industry/University Cooperative Research Centers Program, whospent six
months (June-December 1995) in Japan as a visiting researcher at the
Mechanical Engineering Laboratory of the Agency of Industrial Science
and Technology, Ministry of International Trade and Industry (MITI). His
research stay in Japan was supported by NSF and a Science and Technology
Agency of Japan fellowship. Questions regarding this report should be
directed to Dr. Lee at jalee@nsf.gov.

BACKGROUND

The Japanese machine tool industry\'s rise must be viewed in the context
of Japan\'s dramatic postwar economic successes. Strictly speaking,
Japan\'s machine tool makers benefited from the surge in the demand for
machine tools in their home market, which has grown from less than \$2
billion to more than \$7 billion between 1975-1991. The investment
boomed the competition and it also generated constant pressure on
machine tool makers to come upwith new improvements in flexible
manufacturing systems. The government intensified this pressure by
passing a law which stipulated that half of all machine tools produced
should be CNC by 1977. This pressure for innovation was reinforced by
the rapid turnaround time of the large machine tool investors,
whotypically expect to use a machine for as little as five years before
purchasing a more sophisticated model. At the time when major
investments were required in the new CNC technology,Japanese
manufacturing also benefited from low cost of capital. The productivity
in Japan\'s machine tool industry has remained stagnant or declined
after the bubble economy. For the past twoyears, the Japanese business
and economic press have engaged in adebate over the future of Japan\'s
economic performance in the\"post-bubble\" era. Many companies feel that
they have \"overinvested\" in plant and equipment , especially in
automation,during the bubble period. Machine tool demand in recent years
isless than one-half its 1990 peak during the bubble economy. Recent
sales from major machine tool builders and componentsuppliers, such as
Fanuc, Hitachi-Seiki, Okamoto, etc. havedropped 30-40% since 1990. Many
machine tools makers, including KYC Machine Industry Co. Ltd., Sodick
Co. Ltd. (a EDM machinemaker), THK, Sumitomo Heavy Industries, Ltd., and
Mitsubishi Heavy Industries, have developed joint ventures with
industries

in China to develop future market in China.

Today, machine tool customers in Japan are looking for machinesto last
more than ten years. They ask for reliable guide way(integrated steel
and iron casting guide way), better structure (thermally controlled),
high speed spindle (typically 16,000-40,000 rpm with 50 tapers), better
drive (linear motor), andsmart controller (AI-based controller).

As for production practices, Japanese manufacturers areconstantly
benchmarking high quality manufacturing operations. In general,
temperature controlled (20 degrees C plus/minus 1) production facilities
are commonly used by machine tool builders.

Most Japanese manufacturers have very strict testing procedures for
their products. For example, Fanuc tests every machine (i.e.laser
cutting machine) it builds for 100 hours prior to shipping.

In the robot industry, Yaskawa Electric Mfg. Co., MatsushitaElectric,
and Fanuc have reported increased sales this year. Fanuc produces about
800 robots per month. Exports to Southeast Asia are increasing. In
general, domestic robot sales have not

increased very much. The total robot production declined from 6 billion
in 1991 to 4 billion in 1994. Currently there are about 400,000 robots
in use in Japan. It is predicted that it will be increased to 470,000 in
1997. Fanuc recently demonstrated a two-arm robot for assembly
applications. Toshiba, Hitachi, and Mitsubishi are engaged in research
on new controllers to be enclosed inside the robot base. Hitachi-Seiki
also has demonstrated the fastest assembly robot which is a parallel
mechanism with four parallel links. It can package 150 cookies per
minute. Most research activities in the universities are involved in
autonomous reasoning and smart mechanism. Researchers at the Mechanical
Engineering Lab. are leading the most advanced robotics research in the
areas of micro hand module using parallel link mechanism, service
robotics (i.e. health service robots and excavation robots), 6-legged
walking robots, and autonomous manipulation of objects with multiple
fingers. Yaskawa Electric has also demonstrated a two-arm service robot
for repairing the power lines between power posts.

In the FMS industry, sales have been declining since 1990. In addition,
many companies are reevaluating the FMS which were invested in during
the 1980s. The general complaint is that theflexibility of the FMS is
heavily dependent upon the software, but most factory engineers have
encountered a lot of difficulties to implement new production functions
on the existing software system. As a result, operators and engineers
have no flexibility to quickly re-configure production operation to meet
customers\'desires. Okamoto Machine Works\' Annka plant has totally torn
down its FMS which was built in the early 1980s, due to high maintenance
cost and inflexibility. In viewing the changing needs from industry,
Hitachi Seiki in 1993 developed a Holonical Manufacturing System (HMS) -
a manufacturing cell integrated with a \"bottom-up\" production control
system instead of a \"top-down\"system which is traditionally used by
the FMS. Currently, it claims that the HMS has gained some popularity in
industry and sales are increasing.

In construction machinery industry, major construction machine tool
makers, including Komatsu Construction Machinery Co. Ltd.and Hitachi
Machinery Co. Ltd., began joint venture projects in China one after
another. Komatsu and Hitachi have developed joint operations with
companies in China. It is the current trend that Japanese machinery
makers are envisioning the establishment of export bases for the
Southeast Asia market to circumvent the yen appreciation problem.

STATUS ON RESEARCH AND PRODUCTION PRACTICES

Customers are demanding innovation constantly in Japan. For example, the
push for flexible manufacturing capabilities in the automotive
industries created the need for more flexible machine tools, which could
be quickly transformed to perform a variety of tasks. A common trend in
the CIM is to make systems more versatile so that they run a variety of
parts for mass customization. In addition, pressure to innovate has also
been heightened by the severe labor shortages that began to appear in
the late 1980s. These trends have created a further boost for firms to
increase automation through investment in manufacturing equipment. This
section will highlight the production practices and current
technological status in the machine tool industry.

Research activities in advancing the state-of-the-art manufacturing
technologies are discussed as well.

High Speed Spindles Mazak has claimed that customers complained that
spindle bearings needed to be re-adjusted and replaced almost every
year. Hitachi-Seiki indicated that the 16,000 - 20,000 rpm is their
standard design for their products. Some customers are looking for
40,000 rpm for special applications. They believe that spindle under
20,000 is more realistic for manufacturing industry in Japan.

Linear Motor Drive

The Linear motor has been becoming popular in many applications. Now the
feeding speed of NC machine tools is generally more than 20 m/min., and
60 m/min. has appeared. With the increase in speed, vibration and noise
have been causing problems in using ball screws. In addition, NSK has
indicated that its mechatronics customers are constantly requesting
linear motor type positioning tables for semiconductor manufacturing
instead of the traditional ball screw due to its fast wear out rate.
Fanuc has developed partnership with Anorad Corp. in the United States
to deploy Anorad\'s linear motor for Fanuc\'s laser cutting machines and
part profiling machines. Research activities are also conducted by
Professor Kakino at the Kyoto Univ. to evaluate the performance of high
speed machining by using linear motor for Toyota Motors. Hitachi-Seiki
indicated that the use of linear motor for machine table on CNCs is very
expensive. In addition, there is a lack of thrust torque for machining.
Hitachi-Seikiclaimed that they need to use two linear motors side by
side to replace a traditional lead screw drive. Another concern is that
the size of the amplifier is bigger than the traditional one.

Guide Way

Integrated steel and iron casting guide ways are very popular for heavy
machining applications in Japan even though the cost is 20 percent
higher than the conventional ones. Auto makers in Japan are looking for
machine tools which can last longer (more than 10 years) to increase the
long-term reliability.. Okamoto Machine Tool Works also has added Teflon
strip onto the guide way to reduce the friction for its precision
grinders. Prof. Aoyama in Keio University is investigating the use of
electro-rheological (ER) fluid for the dynamic performance enhancement
of machine tool table. Research results show that the vibration of the
table has been reduced by applying 3 kv/mm electric field on ER fluid.

Cutting Tools and Inserts

The most common insert materials in Japan are coated carbide (58%),
cermet (28%), and cermeted carbide (24%) , in contrast to tungsten
carbide in the United States. Cermets are ceramic particles dispersed in
a metal matrix (oxide or carbide-based).

Cermets combine the high-temperature resistance of ceramics with the
toughness and ductility of carbides. With the trend in high speed
machining and high speed finishing, 72% of world cermet cutting tools
are used in Japan. The most popular coated carbide tools are coated on
the 0.5 mm substrate with 6-8 microns TiCN,and then 2-3 microns Al2O3,
and 0.5 microns TiN in the outer layer. Diamond coating with CVD
(Chemical Vapor Deposition) process is also very popular in Japan these
days. Mitsubishi diamond-coated DC46 inserts are coated with about 5
microns in thickness. It lasts three times longer than that of cermeted
carbide tools. The problem with diamond-coated tools is the adhesion
strength layer. Each manufacturing company has been trying various
methods. For example, the machining of aluminum alloy with a high
content of silicon (18 %) requires tools with coated diamond layers over
10 microns and the adhension strength is critical. Mitsubishi sells
diamond coated inserts at about four times (\$20) the price of the
carbide coated inserts (\$5). Sumitomo Electric Industries Ltd. is
developing new CVD diamond thick-plate brazed tools. CVD diamond thick
plate of 0.2-0.5 mm in thickness is brazed onto the surface of superhard
alloy cutting tools in a similar fashion as sintered diamond plate
brazed tools. The performance difference for machining general aluminum
alloys is not great between CVD diamond and sintered diamond brazed
tools. However, for aluminum alloy containing 18% silicon whose
practical use is becoming popular in Japan, the CVDthick-plate brazed
tools surpass other tools.

Many companies are also using (TiAl)N coated tools which were coated
with the Physical Vapor Deposition (PVD) for high speed machining. PVD
generates (a plasma of) energetic ions that bombard the substrate\'s
surface and allows varying aluminium and nitrogen ratios almost at will.
PVD also delivers finer grains. As a result, it reduces the chances of
cracking and leaves a smoother finish.

Mitsubishi Materials, Sumitomo, and Toshiba are the three major cutting
tools and inserts producers in Japan which dominate over 50 percent of
the domestic market in Japan. Today Mitsubishi Materials has 7 percent
of the world market share and 21 percent domestic market share. Other
foreign competitors include Kennametal (13% of the world market share),
Valenite (recently acquired by the Cincinnati Milacron), Sandvik (30% of
the world market share), and Iscar (an Israeli company which is famous
for grooving and deep cutting inserts). Recently Mitsubishi also
developed an automatic insert feeding tool holder for Toyota to reduce
the tooling set-up time and to eliminate possible clamping misadjustment
by unskilled workers. This function is essential to assure production
performance for overseas facilities in the developing countries.

Tool Monitoring and Sensing

In general, most manufacturers use the cutting time for the criteria of
the tool life in machining applications. Mitsubishi is jointly
undertaking prototype testing of a non-contact magnetostrictive
monitoring of the milling cutter with Professor Inasaki at Keio
University. Prof. Inasaki has developed a non-contact tool cutting force
measurement technique by using magnetostrictive sensors mounted on the
tool holder. A long and slender film which is composed of strong
magnetic materials =46e-Ni-Mo-B are deposited on a cutting tool shank
with an angle of -45 and +45 degree to the center axis of the tool
shank. This system detects radial force, thrust force, and torque by
applying the magnetostrictive effects. The results have shown better
performance than the Kistler dynamometer.

Prof. Inasaki also developed a sensing system for monitoring grinding
process. A CBN wheel with a built-in AE sensing system, including
batteries, FM transmitter, and signal processing circuits, has been
developed. This is an excellent method for monitoring conditioning
process when the super abrasive wheels are used.

Thermal Compensation/Control Technique

To increase productivity, machine tool users are demanding higher
rotating (20,000-40,000 rpm) and higher feeding speeds (40-60m/min.),
but without sacrificing accuracy. This requires the control of heat
generated by bearings and ball screws. Twoapproaches are generally
considered when trying to control the thermal deformation, error
avoidance approach and error compensation approach. In Japan, error
avoidance techniques are normally implemented at the design stage of a
machine, such as minimizing generated heat, symmetrical structural
design,thermally stable materials, cooling for spindles and ball
screws,and so on. Controlling the thermal behavior by using circulated
coolant through spindle and ball screw are becoming standard practices.
For example, Okamoto Machine Tool Works Ltd. uses a water-cooling system
on the wheelhead for all precision grinders. Hitachi-Seiki uses an oil
circulated system on the spindles for all VMCs (Vertical Machining
Centers). NSK produces a range of sizes of standard hollow ball screws.
Most machine tools in Japan are equipped with manual function for
operators to offset the cutting conditions through constant measurement
of dimensional variation from parts. The typical oil feed rate for
forced cooling is about 1 gal./min. It is claimed that thermal
displacement can be reduced by 30 to 50 percent by using this approach.
Few companies control thermal deformation through software compensation.
Hitachi-Seiki has developed a ATAC10 method (Artificial Intelligence
Thermal Accuracy Control within 10 =B5m range) to off-set the machining
condition to compensate for thermal errors. Basically it linearizes
experimental errors from spindle head, spindle nose, and linear errors.
A prediction can be made based on the linearized chart. Hitachi-Seiki
claimed that the result is very promising.

Controllers

Open controllers are now being implemented by some manufacturers in
Japan. Fanuc\'s CNC 150, 160, 180, and 200 series are open CNCs. In
terms of production, Fanuc still is the largest producer in CNCs. It
produces about 6000 controllers per month (almost 8000 per month during
the bubble period), far more than the annual production of any U.S. CNC
makers. In addition, Fanuc is implementing artificial intelligence
(A.I.) technologies into its Robocut EDM machines, the Robodrill CNCs.,
and the Roboshot plastics injection molding machines. In the case of
injection molding machines, the controller first learns the pressure
wave of the manually adjusted injecting process. The optimal pattern is
used as a template to monitor the pressure wave and to adjust the
process parameters from all operations thereafter.

Independently from Fanuc, a working group named OSEC (Open System
Environment for Controller) was formed in 1994 to realize an open
architecture in all factory automation equipment. The OSEC consists of
three machine tool builders - Toshiba Machines Co., Toyoda Machine
Works, Ltd. and Yamazaki Mazak Corp., and IBM Japan, Mitsubishi Electric
Corp., and SML Corp. The intent of the OSEC is to develop protocols and
specifications for PC-based open controllers in the factory automation
industry. A report entitled \"Open System Environment for Controller
Architecture\" was released in September, 1995 to serve as a
developmental guide for participants in OSEC. Currently, Mitsubishi is
developing new generation process controllers (i.e. PLCs and NCs) under
MS-DOS. A prototype PC-based NC controller has been demonstrated and is
under testing. Today, Mitsubishi has 45 percent of the market share on
its PLC products in Japan. In addition, Mitsubishi has developed the
first fuzzy controller for the V-series die-sinking electrical discharge
machines (EDM) in Japan. As for the robot controller, Toshiba, Hitachi,
and Mitsubishi all are developing smaller controllers which can be
enclosed inside the machine so that weight can be reduced and less
insulation space is required. Mitsubishi Heavy Industries has, jointly
with Kobe Shipyard & Machinery Works, developed an open-architecture
controller for its portable manipulator.

New Generation Flexible Manufacturing System (FMS)

Many companies in Japan are currently revitalizing their flexible
manufacturing systems which mostly were built in the 1980s. There has
been a generic concern about the effectiveness of the FMS in practice.
Okamoto Machine Works, which was one of Japan\'s FMS demonstration sites
in the early 1980s, has torn down its FMS since they discovered that the
FMS is nothing but a programmable dedicated production system. Today
many companies are investigating new generation FMS to meet the
requirements of the era of mass customization. Hitachi-Seiki\'s
Holonical Manufacturing System (HMS) and Yaskawa\'s Agent-based
DynamicallyDistributed Scheduling System (ADDS) are typical examples.

\* Holonical Manufacturing Cell

Hitachi-Seiki developed a Holonical Manufacturing Cell (system HG500) in
1994 and currently it is used for the production of its CNCs in Abiko
factory. Basically Holonical Manufacturing System is operated under the
\"bottom-up\" production control system instead of the conventional
\"top-down\" type system. Traditionally, the part programs, scheduling,
and operation procedures are assigned from the central control unit.
Then each machine performs the assigned task accordingly. In a Holonical
Manufacturing System the operator decides the priority of the operations
from the stored parts on the buffer storage unit. Each part is randomly
input to the buffer storage unit. Part programs and operations are
retrieved from the data base when the specific part is selected.. As a
result, no scheduling is required. The intent is to meet today\'s
customer-oriented mass production needs. Hitachi-Seiki claimed that over
700 kinds of machine parts have been processed by the system since 1994,
and only 30 percent of the parts are re-occurring parts.

\* Agent-based Dynamically Distributed Scheduling System (ADDS)

ADDS is embedded with a parallel computer/controller, namely the
Parallel Inference Machine (PIM). It breaks up the rigid central
planning process in current factory floor. Each production cell or
section schedules and controls its own workload for quick responses. It
also provides a dynamic rule-based diagnostic function which allows
operators to continuously add new rules to the system.

Environmentally Conscious Practices In Machining

Manufacturers in Japan are searching for developing cutting fluids that
are useful in a wide variety of applications and that can be recycled
easily. More companies are also interested in installing in-house
coolant-and-lubricant recycling facilities. In addition, many companies
are studying methods to eliminate lubricants entirely through the use of
dry processing. One such method is the use of a vacuum suction head,
with compliance controlled by an air cylinder, which encloses the
cutting tools. The pressure difference results in the suction force to
collect the chips to a container for recycling. OKK Machine Works
currently is testing this system on the production floor.

Rapid Prototyping

In Japan, the application of rapid prototyping techniques is gradually
shifting to rapid small lot production of expandable parts. Although
many different types of materials are being used to meet the various
needs, not all products produced by rapid prototyping have reached the
required material performance. To fully utilize the capability of these
techniques, both dimensional shrinkage and distortion for thin-blade
type of surfaces are obstacles that need to be overcome. Currently
stereolithography, selective laser sintering, and laminated object
manufacturing are very popular in Japan. Currently Mitsubishi, Sony,
Mitsui, and Hitachi have reported successes in making prototyped parts.
Companies such as DMEC (Design ModelEngineering Center) Ltd., INCS Inc.
(3D Systems Japan), CMET (Computer Modeling and Engineering Technology),
Teijin Seiki, and Shonan are major rapid prototyping machine makers. The
Soliform made by Teijin Seiki has demonstrated layering speed at 24,000
mm/s and is sold for around \$50K. Helysis, Inc. produces systems for
Laminated Object Manufacturing (LOM) and has developed a joint venture
with Toyoda Machinery. As for the research activities, the first rapid
prototyping research was started by Prof. Nagakawa at the Univ. of Tokyo
in 1979. Currently, technologies in the area of polymer injection
molding dies and ceramics prototyping parts are under investigation. In
addition, Prof. Ikuta at Nagoya Univ. is engaged in research on rapid
prototyping of medical devices.

Software Engineering in Manufacturing

In the software engineering area, major companies have shown strong
activities in the development of manufacturing software, in particular,
for those companies involved in the IMS activities. Komatsu, Mitsubishi
Electric, Hitachi, Fanuc, and Toyota are in partnership with major
universities to develop new generation manufacturing systems in the IMS
projects. Toshiba\'s System & Software Engineering Lab. was established
several years ago to conduct R&D in Artificial Intelligence (AI) systems
technology and software technology. Currently, there are 170 researchers
conducting research activities in the areas of systems, software, and
human interfaces. There are massiveactivities in developing expert
systems, fuzzy logic, neural networks and machine reasoning algorithms
for commercial applications. For example, Toshiba has a target of 90
percent of its home appliances and manufacturing equipment to have fuzzy
and neural functions by the year 2000. The recent focus is on software
products to support cooperative communications, production scheduling,
and CASE users. Japanese talents in \"hardware-based manufacturing\" now
have been re-focused on\"software-based manufacturing.\"

PROSPECTS

Due to the rapid appreciation of the yen, many companies in Japan have
been building their overseas operations, in particular, in the Pacific
Rim, since 1990. Machine tool builders in Japan are looking for ways to
cut down the costs to compete with low cost competitors, such as Fadal
and Haas in the United States. In general, machine tool builders in
Japan are actively using the state-of-the-art technologies. In viewing
the fast growing manufacturing activities in Southeast Asia, companies
in Japan are convinced that innovative technologies, such as remote
diagnostics and communications technologies, are essential for them to
develop products for globalized manufacturing industries. I foresee that
the remote manufacturing system concept will be a vibrant field for
manufacturers in Japan in the next five years.