計測自動制御学会論文集
Online ISSN : 1883-8189
Print ISSN : 0453-4654
ISSN-L : 0453-4654
48 巻, 12 号
選択された号の論文の15件中1~15を表示しています
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論文
  • 西岡 一洋, 角田 悠生, 水永 博己
    2012 年 48 巻 12 号 p. 800-808
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    Transpiration is an important physical phenomenon for plant survival. Transpiration measurements can provide a variety of information on plant productivity. In particular, the study of transpirational properties has contributed to the development of agricultural technologies and plant hydraulic physiology as before. The stem heat balance (SHB) gauge is a useful tool for measuring transpiration related to sap flow through the plant body, since it can be used for non-destructive measurement of the sap flow rate. However, the stem heat balance method suffers from five theoretical and technical problems. In order to solve these problems, we designed a new gauge called “Quad Gage.” We achieved a stable stem heat balance by controlling the temperature of four film heaters using a minute thermistor and microcontroller. Quad Gage zeroed the heat storage and radial heat terms in the stem heat balance equation and enabled the actual measurement of the thermal conductivity of the branch surface. As a result, no assumption is required in the stem heat balance theory. In laboratory and field measurements, Quad Gage exhibited high accuracy similar to that of the calibrated SHB gauge. This improvement of the sap gauge design enabled simplification of the operation for the sap flow gauge, downsizing of the system.
  • — 体積比較器としての実用性 —
    孫 建新, 植木 正明, 上田 和永
    2012 年 48 巻 12 号 p. 809-815
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    The volume or density is one of the very important characteristics for weights. This paper concerns the precise volume measurement of weights. The authors developed a volume measuring apparatus which is based on Boyle's law, and use it as a volume comparator. The volume of weights in a wide mass range can be determined by comparison against a known reference volume. In each comparison, the volumes of the measurement weight and the reference weight are almost equal. The effectiveness of the developed method is verified by a fundamental experiment on weights of 100g to 2kg. For determination of volume of 1kg weights, the expanded uncertainty is evaluated to be 0.048cm3, which is sufficiently applicable to volume measurement of the highest class E1 weights.
  • 下井 信浩, 西條 雅博
    2012 年 48 巻 12 号 p. 816-821
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    Bridge pier joints occasionally become unstable due to deterioration and after the great earthquake disaster. This paper is the outline of smart sensor study executed on upgrading of function and principal specifications of the developed sensor for monitoring stability of bridge pier joints. We have proposed in this system is able to a prototype of monitoring system that easily evaluates the integrity of bridge pier joints quantitatively and easily by vibration analyzing.
  • 千葉 昭宏, 奈良 高明
    2012 年 48 巻 12 号 p. 822-829
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    This paper presents a novel method for the localization of a passive Radio Frequency Identification (RFID) tag in two-dimensional (2D) space. First, in a 2D square domain inside which an RFID tag is freely placed and moved, we show that a line on which the RFID tag exists can be estimated from the weighted integrals of the magnetic field created by the tag along the boundary of the domain. Then, for measuring them, we develop a square-shaped magnetic sensor composed of three coils only: two pairs of oppositely-wound rectangle coils connected in series on the parallel sides of the squared domain, and four bow-tie-shaped coils connected in series on all sides. Using the developed sensor with the side length of 200 mm, a low frequency (135 kHz) RFID tag was localized in the square area 160 mm on the side with the average error 3.6 mm at 80 points.
論文
  • 折本 寿子, 生田 顕
    2012 年 48 巻 12 号 p. 830-836
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    In the actual sound environment system, a specific signal shows various types of probability distribution, and the observation data are usually contaminated by the background noise of non-Gaussian distribution type. Furthermore, there potentially exist various nonlinear correlations in additon to the liner correlation betwen input and output time series. Consequently, often the system input and output relationship in the actual phenomenon cannot be represented by a simple model using only the linear correlation and lower order statistics. In this study, complex sound environment systems difficult to analyze by using usual structural method is considered. By introducing an estimation method of the regression coefficients for conditional moments with several orders under existence of the external noise, a prediction method of output response probability for sound environment systems is theoretically proposed in a suitable form for the additive property of energy variable and the evaluation in desibel scale. The effectiveness of the proposed method is experimentally confirmed by applying it to the observed data in sound enviroment.
  • — 直並列切り換えによるキャパシタの均圧化 —
    竹田 佳史, 永井 裕, 竹田 晴見
    2012 年 48 巻 12 号 p. 837-846
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    In this paper, the charge-and-discharge control method which improves the efficiency of the electric power storage equipment using capacitors is proposed by decreasing the variation in inter-terminal voltages of capacitors resulting from the variation in capacitance. That is, the circuit block is constituted with a pair of capacitors, and two or more switches which switch the capacitors in series or in parallel, and the electric power storage part is constituted by connecting the circuit block to n stage series. And in order to always maintain the output voltage of electric power storage part in the allowable input voltage of an electric power converter, connection of the capacitors in each circuit block is switched in series or in parallel. Furthermore, without using parallel monitor, in the case of charge, by parallelizing preferentially the capacitors in the circuit block with high block voltage, for every short predetermined interval time and in the case of discharge, by serializing preferentially the capacitors in the circuit block with high block voltage, for every short predetermined interval time, the variation in inter-terminal voltages of capacitors is controlled, and the charge-and-discharge efficiency of electric power storage equipment is raised.
  • 脇谷 伸, 大西 義浩, 山本 透
    2012 年 48 巻 12 号 p. 847-853
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    PID controllers have been applied in a lot of industrial processes because its control structure is simple and physical meaning of PID parameters is clear. However the fixed PID controller cannot obtain a desired control performance because most real systems have nonlinearity. As an effective control method for these systems, a controller which has a tuning mechanism of PID parameters by using a Cerebellar Model Articulation Controller (CMAC) has been proposed (i.e, CMAC-PID controller) and the effectiveness of the method has been evaluated. However, it needs long period of time to learn CMAC in an on-line manner, therefore, it becomes a harmful effect to a practical realization of CMAC-PID controller. On the other hand, Virtual Reference Feedback Tuning (VRFT) and Fictitious Reference Iterative Tuning (FRIT) have been attracted much attention as methods which do not utilize system parameters to calculate control parameters. According to these methods, control parameters are computed by using a closed-loop data, thus it is expected to reduce a design procedure of a control system. In this paper, the new off-line learning method of CMAC unified FRIT is proposed. According to this method, CMAC learns its weights by using closed-loop data at off-line, as a result, the above practical problem of CMAC-PID controller can be resolved. Moreover the nonlinearly-expanded FRIT controller is realized by the proposed method. In this paper, the proposed method is first explained and the effectiveness of the proposed method is numerically evaluated by a simulation example.
  • 島 圭介, 杉江 研勇, 芝軒 太郎, 卜 楠, 上野 直広, 吉栖 正生, 辻 敏夫
    2012 年 48 巻 12 号 p. 854-862
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    This paper proposes a novel method of measuring muscle surface deformation using flexible piezoelectric thin film sensors to allow PC operation by people with severe physical disabilities. Piezoelectric signals are first measured using thin film sensors that are flexible, compact and sensitive. Strength and velocity information relating to muscle surface deformation is extracted from the signals measured and used as input for a neural network. In this way, the motions of users can be estimated by learning differences in muscle surface deformation information for particular individuals. A PC can also be operated with only a few motions if an assistive operation mode is introduced. This paper details the development of a mask-type interface with piezoelectric thin film sensors and outlines experiments conducted on the measurement of muscle surface deformation. The results showed that multiple facial motions can be discriminated accurately from the muscle deformation information obtained. PC operation experiments involving three subjects (including one with paralysis from a cervical cord injury) also produced outcomes indicating that a PC can be operated voluntarily based on facial motions by people with severe physical disabilities.
  • 高橋 英二, 迫田 尚和, 朝日 賢一, 福本 陽三
    2012 年 48 巻 12 号 p. 863-871
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    There are high demands in the railway industry for the automated measurement of positions of facilities and the detection of obstacles along the railway for track maintenance. Since the measurement of a large view-area at a high resolution under various disturbances is required, there are problems to be solved in realizing a reliable and stable measurement system that works in the real world. It should be noted that the cost and the ease of use for operators are also crucial issues that are just as important as the technical aspects. We have devised a new method of image processing and an original design of signal processor that meets those demands, and successfully deployed them in practice. In this paper, we report on the developed equipment of detection of obstacles along railway and discuss applying a profile measurement to a large-scale structure.
  • 伊藤 章, 早川 義一
    2012 年 48 巻 12 号 p. 872-881
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    Steer-by-Wire system requires high-level safety. Conventionally, redundancy of sensors, actuators and microprocessors allows the system to be fault tolerance. However, these redundancy systems still have some problems. For example, increase of cost, weight and so on. The purpose of this study is to design fault tolerant control system depending on drive system in place of an additional actuator. The effectiveness of this method has been verified in simulation.
  • 東 俊一, 田淵 絢子, 杉江 俊治
    2012 年 48 巻 12 号 p. 882-888
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    This paper develops a mathematical model of a sheepdog control strategy, in order to clarify a principle for controlling autonomously (and randomly) moving multiple agents. First, by observing real behaviors of a sheepfold and a sheepdog, we extract their essential properties as a multi-agent system. Based on this, difference equations are constructed for the sheep and sheepdog. It is verified by numerical simulations that the proposed model captures their qualitative behaviors.
  • 草野 周, 山下 裕
    2012 年 48 巻 12 号 p. 889-897
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    Grüne et al. (2008) proposed a digital control law approximating the response of a nonlinear continuous-time controlled system. In this research, we improve the Grüne's controller to allow one sampling delay for the calculation time digital computers. Moreover, we focus on only a control Lyapunov function of which accuracy should be maintained. We show that Sontag-type controller satisfies the necessary and sufficient condition of the applicability of the proposed controllers. In addition, we establish a monotonic decrease of a Lyapunov function on any compact set except a neighbourhood of the origin to show the semiglobal practical uniform asymptotical stability of the closed loop system for the proposed method.
  • 江上 正, 天野 桂介
    2012 年 48 巻 12 号 p. 898-906
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    We have previously developed a path control method with minimum desired point search and implemented it to a linear motor table, and we have experimentally verified the effectiveness of the method. In the present study, the path control method is improved and applied to a numerical control (NC) milling machine to examine the method's practicality. In conventional control methods, path error can be minimized, but the problem of large speed variation along the cutting path remains. Maintaining constant speed in the control of NC milling machines is crucial for making cuts with low surface roughness. Accordingly, the improved path control method is proposed, which considers the velocity of the component in the movement direction, in order to control both the speed and position of the cutting tool of NC milling machines. A commercially available NC milling machine is reconfigured to enable switching between the original NC controller and the proposed controller. Slotting and side milling are performed using the proposed path control method, and the control performance of the system is compared with the performance of independent control along each axis and NC controller. Average path error, speed along the path, and cutting surface roughness are examined, and the effectiveness of the proposed path control method is verified.
  • 下市 拓真, 桂 誠一郎
    2012 年 48 巻 12 号 p. 907-912
    発行日: 2012年
    公開日: 2013/01/23
    ジャーナル フリー
    Recently, the real-world haptics which deals with real-world tactile sense has been actively researched. In the real-world haptics, tactile information is dealt with by an actuator as a disturbance force. Therefore, a friction of the actuator has to be minimized for clearer tactile information. If the friction is known in advance, it is able to be compensated by control. So this paper proposes a method of friction identification of an actuator based on optimization problem. Simulated annealing which is solver of the optimization problem is used in the proposal.
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