著者
久野 翔太郎 石川 諭 雉本 信哉 木庭 洋介
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 (ISSN:21879761)
巻号頁・発行日
vol.83, no.854, pp.17-00305-17-00305, 2017 (Released:2017-10-25)
参考文献数
13

Several adaptive feedforward control methods have been proposed in previous research on active noise control. In those methods, noise control is achieved by adding in a reverse-phase control sound of the same amplitude to noise near an error microphone. Because this method is aimed at controlling only noise near the error microphone, the control area is inherently narrow. Here, we propose an alternative method of noise control for an entire closed space. The proposed method is based on state feedback control and modeling of the acoustic space by the concentrated-mass model. The acoustic space is modeled as masses, connecting springs, and connecting dampers. Further, a loudspeaker as control source is also modeled as a mass-spring-damper system. We previously reported a method for simple one-dimensional acoustic space control. In this paper, we show the design of a control system for two-dimensional acoustic spaces. The acoustic space and loudspeakers are modeled in a concentrated-mass model, and the state feedback control system is realized as a Kalman filter with pole placement. The number of degrees of freedom is reduced by using modal analysis, which reduces the computation time of the controller. Experiments and numerical simulation of the coupled system were conducted to confirm the validity of the analysis model. Noise in the acoustic space was experimentally controlled, with the finding that noise in the entire acoustic space was reduced around the resonance frequencies. Furthermore, the limit of the control effect are considered within the proposed system.
著者
雉本 信哉 下嶋 浩 柴原 章宏
出版者
一般社団法人日本機械学会
雑誌
日本機械学会論文集. C編 (ISSN:03875024)
巻号頁・発行日
vol.62, no.596, pp.1397-1402, 1996-04-25
参考文献数
10
被引用文献数
1

A new adaptive control algorithm in the frequency domain was proposed. This frequency domain approach is an alternative to the ordinary filtered-x least mean squares (LMS) algorithm in the time domain. A transfer characteristic of an acoustic path is identified adaptively in the frequency domain using the fast Fourier transform (FFT). The real-time control of the noise reduction in an L-formed duct model was carried out. A digital signal processor and a personal computer were used for the active noise control. The maximum noise reduction level of about 30 dB and the average reduction level of about 7 dB were obtained through the experiment. As a result, it was shown that this frequency domain adaptive algorithm has faster convergence compared to the ordinary filtered-x LMS algorithm.
著者
下嶋 浩 雉本 信哉 佐藤 治 前田 秀 斎藤 敦
出版者
一般社団法人日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.59, no.562, pp.p1803-1808, 1993-06

Motions of human arms are analyzed kinetically and kinematically with respect to smoothness. A kinematic arm model with 6 degrees of freedom is suggested and spatial motions are simulated considering the sum of the weighted square of joint displacements, which approximately equals kinetic energy of the whole arm. A low-pass filter is applied for smoothing the kinetic state variables, i. e. , displacement, velocity, and acceleration, and the smoothing transfomation is optimized from the aspect of characteristics of response and vibration. Such transformation is also applied to the human arm model, and the effects are investigated through simulations.
著者
雉本 信哉 下嶋 浩
出版者
一般社団法人日本機械学会
雑誌
日本機械学会論文集. C編 (ISSN:03875024)
巻号頁・発行日
vol.62, no.598, pp.2272-2277, 1996-06-25
参考文献数
7

In active noise control, the transfer characteristic of an acoustic feedback path has a considerable influence on the stability of the control system. When the acoustic system has a feedback path, the control system often causes unstable behavior called howling. An adaptive howling canceler designed to prevent thin howling is studied in this paper. This adaptive howling canceler estimates the acoustic feedback path and acts to suppress the howling. In this paper, the effect of this adaptive howling canceler was considered for two different adaptive noise control algorithms. One was the conventional filtered-x LMS (least mean squares) algorithm and the other was the frequency-domain adaptive algorithm proposed by the authors. From computer simulations, it was shown that the howling canceler works effectively with the filtered-x LMS algorithm. On the other hand, the control system became unstable with the frequency-domain adaptive algorithm. To alleviate this unstable behavior, variable output gain was considered. A good result was obtained with this variable gain.
著者
雉本 信哉 下嶋 浩 田窪 崇行
出版者
一般社団法人日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.60, no.571, pp.p850-855, 1994-03
被引用文献数
1

An approach for active noise control using structural vibration was proposed. No acoustic instruments such as loud speakers and microphones are necessary in this approach. The adaptive FIR filter using the LMS algorithm was used in the control system. Both a computer simulation and an experiment were carried out. The importance of using a howling canceler with the adaptive FIR filter was shown by the simulation. In the experiment, the vibration of the sidewalls of the duct was used for control. Good results were acquired using the simple controller.
著者
雉本 信哉 下嶋 浩
出版者
一般社団法人日本機械学会
雑誌
日本機械学会論文集. C編 (ISSN:03875024)
巻号頁・発行日
vol.61, no.589, pp.3581-3586, 1995-09-25
参考文献数
9
被引用文献数
4

A new adaptive control algorithm in frequency domain was proposed. This frequency domain approach corresponds to the ordinary filtered-x least mean square (LMS) algorithm in discrete time domain. In this approach, the fast Fourier transform (FFT) was used for converting signals between frequency domain and discrete time domain. Since the computaion processes in these two domains are almost independent with each other, this algorithm can be realized effectively by using two processors. Computer simulations were carried out for investigating convergence characteristics of this approach. As the result of these simulations, it was shown that this algorithm has faster convergence with less computation comparing to the ordinary filtered-x LMS algorithm.
著者
中村 肇 金光 陽一 雉本 信哉 松田 浩一 河島 浩一
出版者
一般社団法人日本機械学会
雑誌
Dynamics & Design Conference
巻号頁・発行日
vol.2003, pp."150-1"-"150-6", 2003-09-16

We are developing an electromagnetically levitated vibration isolationsystem for micro vibration isolation. It supports a floating isolationtable without any mechanical contact by using active magnetic bearings to reduce vibration from a floor. The system aims to regulate the microvibration in 6 degree of freedom. Two kinds of controller are designed and confirmed to levitate the table stably by experiments. A series of simulation show that the controllers have good effect on the vibration isolation.