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Volume 43, Issue 5
Displaying 1-12 of 12 articles from this issue
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Muneaki HIGUCHI, Hisakazu NAKAMURA, Hirokazu NISHITANI2007 Volume 43 Issue 5 Pages 347-356
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSDead-reckoning and star-reckoning are two basic self-localization methods for vehicles, but each method has inherent weaknesses. Sensor-fusion via an extended Kalman filter is a suitable method to compensate these weaknesses. However, the extended Kalman filter requires the stochastics of measurement errors for implementation. In this paper, we propose a new sensor fusion method by using an initial state observer. We confirm the effectiveness and usefulness of our method by computer simulation and experiments for self localization of a two-wheeled mobile robot.View full abstractDownload PDF (4280K) -
For Falling Bodies Drop TestsHiroshi KONDO, Syuuiti KIMURA, Sigeo HONMA2007 Volume 43 Issue 5 Pages 357-362
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSNormally, the calibration of accelerometer is put into practice by setting up an accelerometer on the tip of Hopkinson bar. We pointed out this method is adequate to investigate the characteristics of the dynamic response of accelerometer, but is improper to the calibration of the force measurement. Hereupon, a new calibration method is proposed which causes collisions on Hopkinson bar by a collision body installing an accelerometer. Because the impact acceleration is affected by the contact area between collision and sub-collision bodies, a rubber board holding a stable contact area was used as a sub-collision body in the experiments, and an analysis was made by employing a mass-spring system model which assumed the rubber board as a semi-infinite elastic body. The results revealed the impact forces are proportioned to 0.25 power of the contact area.View full abstractDownload PDF (14045K) -
2nd: Development and Evaluation of the Method Using Transfer FunctionHidenori INAOKA, Masashi SHIMIZU, Akimasa ISHIDA2007 Volume 43 Issue 5 Pages 363-368
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSThis paper deals with a simple measurement method of unsteady flow in the pipeline. In this method, a cylindrical air chamber is arranged in the pipeline, the unsteady flow is absorbed as a change in volume of the air chamber. The unsteady flow rate is measured by using only pressure change of the air chamber caused by its volume change. In this method, the characteristic of the air chamber is utilized for the measurement. The characteristic of the air chamber is described as the relationship between the oscillate Fourier number and amplitude-ratio/phase-shift obtained from the measurement pressure of the air chamber and the adiabatic pressure that would exist for the adiabatic air chamber with the same volume change. Here, the oscillate Fourier number is the dimensionless number determined with the shape of the air chamber and the volume change frequency. In this study, the transfer function was identified from the estimated characteristics of the air chamber. The measured pressure wave was used as an input signal, and the adiabatic pressure wave in time domain was directly calculated from the transfer function. The volume change was simply calculated using the adiabatic pressure, and then unsteady flow rate was estimated. In proposed methods, good agreements were achieved between the measured and the estimated unsteady flow rate, and then the accuracies of these methods were discussed. The pulse wave which has many frequency components was measured by our method, and good agreements were achieved.View full abstractDownload PDF (4485K) -
Tomoaki NAGANO, Toshiyuki KONDO, Koji ITO2007 Volume 43 Issue 5 Pages 369-376
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSBiological motor control system includes some time delay within the neural transmission loop, which makes the motor control unstable. It is well-known that the low-pass filtering for the actuator output can improve the system stability. On the other hand, it is estimated that the renshaw cell in the spinal reflex loop may provide the motor output with the low-pass filtering property. The present paper discusses the motor control mechanism as a hierarchical distributed control system including the time delay, and it is shown that the renshaw cell could contribute toward stabilizing the time delay loop in the hierarchical distributed control system. In addition it is shown that the control system can manage a complex task such as a cooperative problem between posture and motion control.View full abstractDownload PDF (12332K) -
Hiroshi OKU2007 Volume 43 Issue 5 Pages 377-382
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSThis paper concerns subspace model identification of slowly time-varying systems operating in closed-loop. A recursive MOESP-type closed-loop subspace model identification algorithm is developed. The key technique of derivation of the proposed algorithm is the Hessenberg QR algorithm. The exponential forgetting mechanism is introduced into the recursive algorithm in order to track the time variation of the parameters of the systems. A numerical study on a closed-loop identification problem shows the effectiveness of the proposed algorithm.View full abstractDownload PDF (7010K) -
Koichi KOBAYASHI, Jun-ichi IMURA2007 Volume 43 Issue 5 Pages 383-390
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSThis paper discusses a new approach to representing a finite automaton as a combination of a linear state equation with a smaller set of free binary variables (i. e., input variables) and binary inequalities, in order to reduce the computational time for solving the model predictive control problem of a class of hybrid systems. In particular, this paper is devoted to proving that a system representation derived by our proposed method is minimal in the sense that the number of its binary input variables is minimal among system models over all linear equivalence transformations that preserve the binary property of free (input) variables.View full abstractDownload PDF (4385K) -
Naoya WAKAYAMA, Kazuhiro YUBAI, Junji HIRAI2007 Volume 43 Issue 5 Pages 391-399
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSThis paper proposes the data-driven method named Fictitious Correlation-based Tuning (FCbT) for the tuning of Linear Time Invariant (LTI) multivariable controllers. The parameters of the controller are updated directly using the data acquired in closed-loop operation. This approach allows one to tune diagonal elements of the controller transfer function matrix to satisfy the desired closed-loop performance, while the other elements are tuned to mutually decouple the closed-loop outputs. Moreover, FCbT requires only one-shot experimental data for an off-line nonlinear optimization in order to obtain the optimal parameter minimizing a “fictitious” crosscorrelation function. FCbT is compared with standard Correlation-based Tuning (CbT) for MIMO systems in some simulations.View full abstractDownload PDF (4880K) -
Masatoshi HADA, Toshio TSUJI2007 Volume 43 Issue 5 Pages 400-407
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSThis paper deals with a design method for layout of controls based on the equivalent inertia of human-machine systems. In this method, both the human and the object are modeled as articulated rigid bodies, and the posture of the human, the configuration of the object, the contacts between the human and the object, and the constraints on the human and on the object are respectively definded prior to the analysis. The equivalent inertia of the human-machine system is then calculated at some points on the object taking the contacts and the constraints into consideration. Finally, optimization is carried out by choosing design variables and by employing the indices of equivalent inertia as the objective function. In this paper, layout designs of a steering wheel and an accelerator pedal optimized by using newly defined effective and ineffective equivalent inertia indices, are compared with subjective layout evaluated by human drivers. The results show the effectiveness of this method to design user-friendly layout for various physical sized drivers.View full abstractDownload PDF (25699K) -
Akira OHSUMI, Shiro KOMIYAMA, Masahiko WATANABE, Masataka KASHIWAGI, T ...2007 Volume 43 Issue 5 Pages 408-417
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSA joint method is proposed for estimating the water quality in terms of BOD and DO and idenfitying both unknown magnitude and discharged location of the polluted load from noisy measurements on the BOD and DO. In order to detect the discharged load, the innovation process for the water quality plays an important role, and the idea of pseudo-measurement is introduced to identify the unknown magnitude of the pollutive load for both cases of the point-source and nonpoint-source loads. The joint estimation and identification method is tested by simulation studies.View full abstractDownload PDF (5067K) -
Teppei TSUJITA, Atsushi KONNO, Masaru UCHIYAMA2007 Volume 43 Issue 5 Pages 418-427
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSIn order to achieve human-like quick eye movements and image processing for intelligent mobile robots, a high speed binocular camera head is developed. The aim of the binocular camera head is to provide a platform to reproduce the human brain information processing. Two neuromorphic vision chips with lenses, which are developed imitating human retinas, will be mounted on the camera head. The camera head has an azimuth DOF for each camera and a common elevation DOF. Therefore, total number of DOF is three. The weight of the robot head is strictly limited, since it is mounted on a mobile robot. In order to satisfy both demands for the quick movements and light weight, the camera head is designed based upon a simple parallel mechanism. Consequently, all motors are mounted on the base. The characteristics of the camera head are quickness in motion, lightness in weight and simplicity of the mechanism. This paper presents the design, development and evaluation of the camera head. The inverse and forward kinematics are also discussed in this paper.View full abstractDownload PDF (19511K) -
Shohei TANIGUCHI, Ryuta OZAWA, Sadao KAWAMURA2007 Volume 43 Issue 5 Pages 428-434
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSWe propose a new method to identify inertial parameters of a human body applying passive motion. The method extracts an inertia torque component from total torque components by a joint torque decomposition method based on time-scale transformation. Furthermore, inertia parameters are identified with the extracted inertia torque component. In this paper, we describe the detail of the proposed method, and excute experiments to confirm its effects.View full abstractDownload PDF (4917K) -
Tetsuya KIMURA, Masahiro ISHIZAKI2007 Volume 43 Issue 5 Pages 435-437
Published: May 31, 2007
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSIn this paper, an operating board with three position switches is developed in order to reduce the risk caused by disturbance in rescue site, where misuse of operator and uncertainty of the rescue environment are considered. The effectiveness is evaluated experimentally.View full abstractDownload PDF (4079K)
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