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Volume 39, Issue 10
Displaying 1-13 of 13 articles from this issue
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Akio YAMANE, Taketoshi IYOTA, Yongwoon CHOI, Yuzuru KUBOTA, Kazuhiro W ...2003 Volume 39 Issue 10 Pages 879-886
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn order to develop an indoor, local positioning system and evaluate its ranging accuracy, range measurement experiments have been performed using spread spectrum sound waves at audio frequencies of 0.69, 3.0, and 10kHz, for which a relatively broad frequency response can be readily prepared by means of a pair of transmitter-receiver commercially available. A series of the experiments based on the demodulation of spread spectrum sound signals due to M-sequence (Pseudo Random Noise Code) with a 127-code length showed that the range measurement successfully yielded full-scaled ranging errors of less than 1% as the accuracy for the frequencies of 0.69 and 3.0kHz, and much smaller value of 0.037% for the full scale distance of 18m in the case of 10kHz. The capabilities of noise rejection to super-imposed white noise and signal discrimination between two different M-sequence codes have been also ensured for the phase shift keying modulation on longitudinal elastic waves. Discussions on the measurement precision are interestingly given in terms of the frequency of carrier wave and the traveling distance during the phase shift chip period as an analogy of pseudorange measurements in the global positioning systems.View full abstractDownload PDF (1588K) -
Yusuke SEGAWA, Masaki HOKARI, Kajiro WATANABE2003 Volume 39 Issue 10 Pages 887-895
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper describes a novel method to measure the loci and attitudes of a high-speed moving object in 3-D space. Here we apply the method to measure those of the golf driver head when swinging. The sensor employed in the measurement method is a line-CCD camera with high speed scanning. Because the camera captures only 1-line information in 2-D image, the scanning speed is very high in principle. In the measurement, the line-CCD camera captures the positions of markers marked on the driver head in the local coordinate and the simple signal processing yields the position every scan interval and estimates the loci and attitudes in the global coordinate.
The method was developed for golf head motion measurement, but it can applied to variety of high-speed moving objects other than the driver head.View full abstractDownload PDF (3685K) -
Kenzo OBATA, Kentaro NOGUCHI, Yoshiaki TADOKORO2003 Volume 39 Issue 10 Pages 896-903
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSWe have considered new sound source location algorithms for one receiving point noticing a formant frequency. The automatic operation of the sound image localization is necessary for position estimation of a sound source in a large-scale building space like an auditorium. We measure sound source locations using the phase difference of a formant frequency between three microphones and the height of the receiving point. Normally the formant frequency has some fluctuation. Therefore, we propose two types of new sound source localization methods. One is to track the fluctuating formant component by selecting the maximum components of the fast Fourier transform (FFT) results of the bandpass filter outputs. Another is to estimate the fluctuating formant frequency by the zero-crossing detection and to apply to the Fourier transform (FT). Both methods use a echo avoidance method by the detection of the occurrence of the formant signal. From some experiments, we show that the proposed system can detect the stationary sound source location with the errors less than 0.6m and track the moving sound source under the echo environment.View full abstractDownload PDF (1707K) -
Kenji NAGASE, Hirotaka OJIMA, Yoshikazu HAYAKAWA2003 Volume 39 Issue 10 Pages 904-913
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis study considers realization of the wave control for the uniformly varying damped mass-spring systems controlled by the active mass dampers (AMD). We first derive a necessary and sufficient condition for the exact impedance matching to ensure the internal stability. Since the condition is very restrictive and we also need to prevent the drift of the AMD in practice, we next consider the relaxed impedance matching condition and propose a control design method to realize the relaxed impedance matching and to prevent the drift of the AMD. As a design example of the proposed method, the wave control for the multi-story structure is also presented. Efficiency of the controller is examined numerically and experimentally.View full abstractDownload PDF (2161K) -
Yoshihiko MIYASATO2003 Volume 39 Issue 10 Pages 914-923
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA new class of adaptive nonlinear H∞ control systems for processes with bounded variations of parameters, is proposed in this manuscript. Those control schemes are derived as solutions of particular nonlinear H∞ control problems, where unknown system parameters are regarded as exogenous disturbances to the processes, and thus, in the resulting control systems, the L2 gains from system parameters to generalized outputs are made less than γ. The proposed control strategy can be applied to any time-varying (or time-invariant) systems, and the resulting control systems are bounded for arbitrarily large but bounded variations of time-varying parameters. Also, the control schemes are shown to be sub-optimal to some H∞ cost functionals (or certain differential games), when the high-frequency gains are time-invariant.View full abstractDownload PDF (1412K) -
Masashi NAKAMOTO2003 Volume 39 Issue 10 Pages 924-932
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a modification of iterative feedback tuning (IFT) method based on a practical point of view. Iterative feedback tuning method is a direct procedure to search controller parameters. In order to apply this method to process control, especially the process with steady states, the performance index and the test procedure will be modified. Experimental tests show usefulness of the proposed modifications.View full abstractDownload PDF (1992K) -
Shun-ichi AZUMA, Jun-ichi IMURA2003 Volume 39 Issue 10 Pages 933-941
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper discusses the optimal continuous-time control problem of a class of continuous-time piecewise affine (PWA) systems with the sampled-data autonomous switching, which we call here the sampled-data PWA systems. First, the optimal continuous-time controller is derived for the finite-time optimal control problem. Next, as an application of this approach, we formulate the high-speed and energy-saving control problem of the CPU processing, and show the validity of the approach by simulation.View full abstractDownload PDF (1997K) -
Hiroshi MAEDA, Tomohito MURAKAMI, Tohru IRIE2003 Volume 39 Issue 10 Pages 942-951
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSWe proposed a new stereo matching algorithm based on synergetics. This method must numerically solve differential equations called order parameter equations of synergetics in order to find out the correspondence points between a left image and a right image. This led to the increase of computation time for a complex image. Then, we are investigating a stereo matching algorithm without numerically solving the order parameter equations. For this purpose, this paper theoretically studies the order parameter equations of synergetics and then gives some knowledge with respect to singular points and their structure.View full abstractDownload PDF (1786K) -
Tomoaki KOMATSU, Yoshihiro MIYAKE2003 Volume 39 Issue 10 Pages 952-960
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA predictive behavior called "negative asynchrony" is well known in the sensory-motor coupling. This phenomenon means motion timings precede the cyclic onset of stimuli, and it is commonly observed in the synchronization tapping task. With the use of dual-task method, Miyake et al. had already analyzed this phenomenon and reported two types of anticipatory timing control. However, in such previous researches, the tapping task has been investigated by statistical analysis of synchronization errors (SE). In this report, we assume that the asynchronous displacement has temporal structure. And time-series analysis was applied to clarify it in frequency response. As a consequence, it was shown that anticipatory behavior in the tapping task had two different characters corresponding to two types of anticipatory timing control. One is characterized by a 1/fn power-law relation between spectral power and frequency. The other is characterized by the combination of the significant peak of pacing stimuli and a white noise.View full abstractDownload PDF (2168K) -
Takeshi INABA, Yoshiki MATSUO2003 Volume 39 Issue 10 Pages 961-969
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, control system design of human-machine cooperative systems considering maneuverability is investigated. First, the representative past studies are reviewed and essential characteristics of controlled systems are summarized as 4 transfer functions: the tool dynamics, the reaction force transfer function, the maneuver transfer function, and the transfer function of object dynamics variation. Secondly, parametrization of a general structure of control systems stabilizing the tool dynamics is presented. On the basis of the parametrization, it is clarified that the control systems have two degrees of design freedom, and the relationships among those 4 transfer functions are derived and discussed. Thirdly, it is experimentally verified that previous observations by the authors on dynamics self-shaping characteristics of a human operator in a manual control system are also found similar in human-machine cooperative systems, and that the knowledge can be used for specifying desirable frequency characteristics of the maneuver transfer function. Then, a control design procedure utilizing the full 2 degree of freedom is proposed. An example human-machine cooperative system is designed so that its maneuver transfer function is shaped suitably corresponding to the dynamics self-shaping characteristics of the operator, as well as the transfer function of object dynamics variation is compensated to have a gain large enough to enable the operator to recognize a small variation. Finally, experiments are carried out to confirm the validity of the proposed design procedure.View full abstractDownload PDF (3668K) -
Ryo KIKUUWE, Tsuneo YOSHIKAWA2003 Volume 39 Issue 10 Pages 970-977
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSUsing the impedance perception technique, which we previously proposed, the stiffness matrix which constrains the motion-force relation of the robot's end-effector is estimated on-line, and the uncertainties of the estimates are evaluated. This paper proposes a method of extracting information on local properties of a cylindrical curved surface, including normal direction, primary directions, curvature, and stiffness and friction coefficients, from the stiffness matrix obtained under the situation where the end-effector is slid on the surface. This technique can be implemented as an encapsulated perception function independent from control strategies, and thus it can be used for both autonomous and remote-controlled robots, and for directory monitoring human manipulations. Results of preliminary experiments are presented.View full abstractDownload PDF (3712K) -
Kazuki SHIMIZU, Junichi TAKAMURA, Toshiyuki TANAKA2003 Volume 39 Issue 10 Pages 978-980
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSGPS is a positioning system using signal of satellites. This paper deals with improvement of error in GPS Standard Positioning Service. We proposed the error reducing method using only software. We used only satellites information for improvement of error.View full abstractDownload PDF (466K) -
Koichi KOBAYASHI, Tsuyoshi KIYAMA, Toshiyuki KITAMORI2003 Volume 39 Issue 10 Pages 981-983
Published: October 31, 2003
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe Smith's method to remove the deadtime of a controlled object out of the control loop is well known. This paper proposes a new method of control system design for an MIMO controlled object having non-minimum characteristics to achieve the same effect with no extra compensator. Design formulae are derived and effectiveness of the method is shown through some numerical examples.View full abstractDownload PDF (477K)
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