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41.
Sensor Fusion System Using Recurrent Fuzzy Inference 总被引:1,自引:0,他引:1
Futoshi Kobayashi Fumihito Arai Toshio Fukuda Koji Shimojima Makoto Onoda Norimasa Marui 《Journal of Intelligent and Robotic Systems》1998,23(2-4):201-216
In robotic and manufacturing systems, it is difficult to measure the state of systems accurately because of many uncertain factors and noise, and it is very important to estimate the state of systems. We must measure the phenomena of systems by multiple sensors and estimate the state of systems by acquiring information of sensors. However, we can not acquire all of sensor information synchronically, because each sensor has particular sensor information and measuring time. For estimating the state of systems by multiple sensors, a multi-sensor fusion system fusing various sensory information is needed. In this paper, we propose a Recurrent Fuzzy Inference (RFI) with recurrent inputs and apply it to a multi-sensor fusion system for estimating the state of systems. The membership functions of RFI are expressed by Radial Basis Function (RBF) with insensitive ranges. The shape of the membership functions can be adjusted by a learning algorithm. The learning algorithm is based on the steepest descent method and incremental learning which can add new fuzzy rules. The effectiveness of the multi-sensor fusion system using RFI will be shown through a numerical experiment of moving robot and estimation of surface roughness in grinding process. 相似文献
42.
43.
Neuro-fuzzy control of a robotic exoskeleton with EMG signals 总被引:1,自引:0,他引:1
We have been developing robotic exoskeletons to assist motion of physically weak persons such as elderly, disabled, and injured persons. The robotic exoskeleton is controlled basically based on the electromyogram (EMG) signals, since the EMG signals of human muscles are important signals to understand how the user intends to move. Even though the EMG signals contain very important information, however, it is not very easy to predict the user's upper-limb motion (elbow and shoulder motion) based on the EMG signals in real-time because of the difficulty in using the EMG signals as the controller input signals. In this paper, we propose a robotic exoskeleton for human upper-limb motion assist, a hierarchical neuro-fuzzy controller for the robotic exoskeleton, and its adaptation method. 相似文献
44.
A. Bensalah Y. Guyot M. Ito A. Brenier H. Sato T. Fukuda G. Boulon 《Optical Materials》2004,26(4):375
YLiF4 (YLF) single crystals undoped and Yb3+-doped with different concentrations were grown by the Czochralski technique under CF4 atmosphere. Detailed analysis of Yb3+-doped YLF spectroscopy were made to contribute to the determination of energy levels in this host. We are dealing with temperature and concentration dependences of both π and σ polarizations of the infrared (IR) absorption and emission spectra. Raman spectra were also used to give an attempt of interpretation of electronic and vibronic levels. The radiative energy transfer (self-trapping) and strong phonon–electron coupling make the assignment of Yb3+ energy levels difficult. Evaluation of the laser potentiality of this fluoride host is also presented. 相似文献
45.
A. Yoshikawa C. Fujiwara H. Sato T. Nishi H. Ohta T. Fukuda Y. Waseda G. Boulon M. Ito Y. Guyot K. Lebbou 《Optical Materials》2004,26(4):385
Ca8(La,Yb)2(PO4)6O2 (Yb:CLPA) single crystals with the apatite-type structure could be grown from the melt using the Czochralski method. Grown crystal was 18 mm in diameter and 110 mm in length. It is transparent with slightly blue color. Neither visible inclusion nor crack was observed. Thermal conductivity of Yb:CLPA was calculated from the values of thermal diffusivity, heat capacity measurement and density. Luminescent characterization was carried out from the results of emission, absorption and Raman spectrum. 相似文献
46.
Scott L. Huang Matthew T. Bray Satoshi Akagawa Masami Fukuda 《Canadian Metallurgical Quarterly》2004,18(1):2-34
A large scale 105-m-long, 0.9-m-diam chilled pipeline experiment was conducted to assess the response of a production pipeline that transits between unfrozen (seasonally frozen) and permafrost soils in discontinuous permafrost regions. Thermal and heave characteristics of the experiment for a three-year monitoring period are reported. In response to the chilled pipeline, the progressive cooling patterns within the permafrost and unfrozen soils were different, resulting in the development of a thermal boundary at the transition zone between the two thermally different soils. The absolute maximum movement of pipeline was 0.197 m near the thermal boundary, resulting in a differential heave of 0.148 m. Three distinct heave phases were identified within the unfrozen soil. Phase 1 of the first 200 days related to penetration and heave above the groundwater table and was characterized by heave rates between 0.211 and 0.237 mm/day. Phase 2 resulted in increased ice segregation due to interaction of the freez-ing front with the groundwater table. This phase lasted from approximately day200 to day 500 and corresponded to a heave rate from 0.206 to 0.313 mm/day. Phase 3 was characterized by a further decrease in the heave rate to about 0.081 mm/day and lasted from approximately day 500 to day 1,056. 相似文献
47.
A new mathematical method of estimating the state for uncertain continuous-time multiple-input multiple-output minimum-phase (with respect to the relation between the disturbance and the output) dynamical systems with arbitrarily relative degrees is presented. For the systems with relative degree one, the state observer which is perfectly robust to disturbances is constructed by using only the input and output information. The estimating error of the state decays to zero exponentially. For the systems with higher relative degrees, the state observer is formulated for the first time, where the input and output information, and the a priori information of the upper and lower bounds of the disturbances are employed. In this case, the estimating error of the state can be controlled to be as small as is needed by the design parameters. The attraction of the proposed observers lies in their robustness to disturbances and insensitivity to the high-frequency noises accompanying the inputs. A design example and its simulation results are presented to illustrate the proposed algorithm. 相似文献
48.
Junji Fukuda Shintaro Takahashi Tatsuya Osaki Naoto Mochizuki Hiroaki Suzuki 《Science and Technology of Advanced Materials》2012,13(6)
Plugs, i.e. droplets formed in a microchannel, may revolutionize microfluidic cell-based assays. This study describes a microdevice that handles nanolitre-scale liquid plugs for the preparation of various culture setups and subsequent cellular assays. An important feature of this mode of liquid operation is that the recirculation flow generated inside the plug promotes the rapid mixing of different solutions after plugs are merged, and it keeps cell suspensions homogeneous. Thus, serial dilutions of reagents and cell suspensions with different cell densities and cell types were rapidly performed using nanolitres of solution. Cells seeded through the plug processing grew well in the microdevice, and subsequent plug processing was used to detect the glucose consumption of cells and cellular responses to anticancer agents. The plug-based microdevice may provide a useful platform for cell-based assay systems in various fields, including fundamental cell biology and drug screening applications. 相似文献
49.
Shinji Fukuda Kazuhiko Shimada Noriya Izu Hiroyuki Miyazaki Shoji Iwakiri Kiyoshi Hirao 《Journal of Materials Science: Materials in Electronics》2018,29(14):11688-11698
We observed crack generation and structural changes in electroless nickel–phosphorus (Ni–P) plating layers formed on copper-metalized silicon nitride substrates both during thermal cycling from ? 40 to 250 °C and during storage (not cycling) at 250 °C in order to investigate the effect of the phosphorus contents on crack generation and growth in the Ni–P platings. The used platings contained phosphorus at three different contents: 2.1 wt% [Ni–P(low)], 6.5 wt% [Ni–P(med)], and 10.9 wt% [Ni–P(high)]. The generation time and the amount of cracks were strongly dependent on their phosphorus contents. More cracks appeared after thermal cycling than after storage at 250 °C. In Ni–P(low), cracks were generated after 200 thermal cycles, whereas no cracks were observed even after 250 h of storage at 250 °C. In Ni–P(med) and Ni–P(high), both during thermal cycling and storage at 250 °C, cracks formed during or after crystallization of the amorphous layers. These results suggest that the primary factors affecting the generation of cracks in electroless Ni–P platings are crystallization of the Ni–P platings and repeated changes in thermal stress. 相似文献
50.