Abstract
〈Vol.1 No.5(2008.9)〉
Titles
▲
■ TELEsarPHONE: Mutual Telexistence Master-Slave Communication System
based on Retroreflective Projection Technology
The Universityof Tokyo ・Susumu Tachi, Naoki Kawakami,
Hideaki Nii, Koichi Watanabe and Kouta Minamizawa
TELEsarPHONE is a conceptual prototype of a mutual telexistence system, designed for face-to-face telecommunication via robots. Because of the development of telexistence technology, we can acquire a feeling that we are present in several actual remote places using remote robots as our surrogates and can work and act freely there. However, people in the place where someone telexists using a robot see only the robot, and they cannot feel the existence of the telexisting person. Mutual telexistence aims to solve this problem so that the existence of a telexisting person (visitor) is apparent to the people in the remote environment by providing mutual sensations of presence. On the basis of the concept of mutual telexistence, we have designed and developed a prototype of a telexistence master-slave system for remote communication by applying rretroreflective projection technology. In the TELEsarPHONE system, the face and chest of the slave robot TELESAR II are covered by retroreflective material. To provide the feeling of existence, the real-time image of the visitor is projected onto the robot so that people can see the visitor in real time.
▲
■ Applications of a Controller Desgin Method for Nonholonomic Systems
to Auto-Steering Vehicles
Kawasaki Heavy Industries・Masanori HAMAMATSU, Tetsuya KUBOTA,
Yukinobu KHONO, and Nichijo Manufacturing Co., Ltd,・Shinichi IWATA
In the industrial field of the motion control, many objects are regarded as nonholonomic systems that are difficult to control by static state feedback. The chained form approach is known as a design method of controllers for nonholonomic systems, but a time-state control form that is applicable to a broader class of nonholonomic systems is proposed. This paper describes three applications of a controller designed to utilize the time-state control form for the motion control of the following ground vehicles: a large-scale transfer crane, a rotary snow remover, and the mobile field of the Sapporo Dome stadium. In the first two examples, we try to develop a control function in a time-state control form into an integral type, and the combination of a filter and the Smith compensation. In the last example, we confirm the validity of the motion control by computer simulation prior to actual experiment.
▲
■ Breakthrough Control Technologies in the Japanese Steel Industry
Tadaaki IWAMURA
The Japanese steel industry started to progress in the 1950s and reached maximum production in the 1970s.
In the 1980s it changed its policy of pursuing quantity in production to
pursuing quality. A slight decrease in production levels at the beginning
of 2000 followed, but the industry has recently recovered production quantity
while maintaining quality. In the process it has developed and accumulated
a variety of innovative technologies, called “Japan original technologies”
which were exported around the world. These are highly advanced control
technologies, including sensors,
controllers and control logics, and other electrical and automated equipment.
This paper introduces some of the technologies developed by the Japanese
steel industry that ushered in a new era in steel making worldwide.
▲
■ Flight Evaluation of GPS Precise Point Positioning for Helicopter Navigation
Department of Aerospace Engineering, National Defense
Academy・ Yutaka Shimizu and Masaaki Murata
In 2006 we reported development and assessment of a precise point positioning
(PPP) software for land vehicular navigation. This paper presents one phase
of the continued study at NDA for further extension of the software to
helicopter navigation. For 3D users, the height-dependent tropospheric
delay is a critical factor, and so the sophisticated correction models
and parameter estimation strategies have to be investigated to mitigate
the delay effect. Since the precise positioning results become available
only after the filter convergence and the filter generally converges rather
slowly, speeding up the convergence has to be taken special attention.
In this paper we proposed some new ideas to cope with this problem, and
tested using GPS helicopter flight data in post-processing. With proposed
techniques including the variable Q and pseudo-observation concept, we
have shown that point positioning accuracy at about decimeter level both
horizontally and vertically has been achieved with improved convergence
within about half an hour. We have also shown that the use of the high-rate
(30-second) satellite clocks rather than the 5-minute clocks further improves
positioning accuracy at sub-decimeter level in each 3D coordinate.
▲
■ Attitude Control of a Flexible Planar Space Robot
ToyotaTechnological Institute and RIKEN・,Tatsuo NARIKIYO,Toyota
Technological Institute・Masanori SAKATA, and Michihiro KAWANISHI
Rigid planar space robot is represented as Caplygin system and its base
attitude can be stabilized by means of geometric phase. However,in cases
when flexible arms are used for control of base attitude, inherent resonance
modes are excited and instability is resulted. In this study we propose
a stabilized controller is synthesized as adaptive tracking control system
convined with sliding mode control to track to the arm trajectories derived
from the geometric phase of the Caplygin system. Usefulness of the proposed
controller is demonstrated by numerical simulations and Laboratory experiments.
▲
■ Graph-Switching Based Modeling of Mode Transition Constraints for Model
Predictive Control of Hybrid Systems
Japan Advanced Institute of Science and Technology・
Koichi KOBAYASHI and Kunihiko HIRAISHI
The model predictive/optimal control problem of hybrid systems is reduced
to a mixed integer quadratic programming (MIQP) problem. However, the MIQP
problem has one serious weakness, i.e., the computation time to solve the
MIQP problem is too long for practical plants. For overcoming this technical
issue, there are several approaches.
In this paper, a modeling of mode transition constraints, which are expressed
by a directed graph, is focused, and a new method to represent a directed
graph is proposed. The effectiveness of the proposed method is shown by
numerical examples on linear switched systems and piecewise linear systems.
▲ ■ Tracking of Humans and Robots using Laser Range Finders
The University of Tokyo・Drazen BRSCIC, Takeshi SASAKI, and Hideki HASHIMOTO
There exist various applications where tracking of humans or robots in
an area is needed. An example of such applications are Intelligent Spaces,
where humans and robots share a common space and their positions are tracked
by a system of sensors in the space. In this paper a system for tracking
both humans and robots that utilizes laser range finders as sensing devices
is described. The details of the extraction of objects from the laser scan,
data association and estimation are given, and results of tracking humans
and robots are described. Calibration of the distributed laser range finders,
which is important for the operation of the tracking system is also described,
both in a manual and automated variant and experimental results are given.
Finally, the inclusion of a laser range finder onboard the mobile robot
in the tracking process is described and accompanied with experimental
results. The distributed fusion of static and onboard sensors is also discussed.
▲
■ Design of an Authoring Tool for Producing User-Adaptive Educational
Material
Kitami Institute of Technology・Satoki ABE , Yoshitaka FUJIWARA , Ibaraki
University・
Shin-ichirou OKADA and Kitami Institute of Technology,Yasunari MAEDA
We are studying a u-learning system called KUSEL, which is characterized
by being user-adaptive, a property achieved by using scenario-driven operation
and a causal network. While highly flexible in providing user adaptability,KUSEL
requires completion of a set or complex tasks for the purpose of creating
educational material. This paper reports on the design of an authoring
tool that facilitates the creation of educational material for KUSEL.
▲ ■ Bias Compensation of Recursive Least Squares Estimate in Closed Loop
Environment
The University of Tokushima・Kenji Ikeda, Yoshio Mogami, and Takao Shimomura
In this paper, an asymptotic bias of the recursive least squares (RLS)
estimate in the closed loop environment is analyzed and its compensation
method is proposed under the assumption that the noise is white. Namely,
a bias compensated RLS method in the closed loop environment based on output
error (OE) model is proposed. A posteriori error is also analyzed for the
estimation of the noise variance.
▲ ■ Security Design of Remote Maintenance System for Nuclear Power Plants
based on ISO/IEC 15408
Mitsubishi Electric Corp. ・Ryosuke WATABE, Tadashi OI, and Yoshio ENDO
This paper presents a security design of remote maintenance system for
nuclear power plants. Based on ISO/IEC 15408, we have listed assets to
be protected, threats to the assets, security objectives against the threats,
and security functional requirements that achieve the security objectives.
Also, we have shown relations between the threats and the security objectives,
and relations between the security objectives and the security functional
requirements. As a result, we have concretized a necessary and sufficient
security design of remote maintenance systems for nuclear power plants
that can protect the instrumentation and control system against intrusion,
impersonation, tapping, obstruction and destruction.
|
