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101.
Takuya Otani Kenji Hashimoto Takaya Isomichi Akira Natsuhara Masanori Sakaguchi Yasuo Kawakami 《Advanced Robotics》2013,27(22):1197-1206
In previous studies, various stabilizing control methods for humanoids during the stance phase while hopping and running were proposed. Although these methods contribute to stability while hopping and running, it is possibility that the control during the flight phase could also affect the stability. In this study, we investigated whether the control during the flight phase can affect the stability of a humanoid while running. To achieve stable hopping, we developed a control system that accounts for the angular momentum of the whole body during the flight phase. In this system, the angular momentum generated by the motion of the lower body in each time interval is calculated during the flight phase, and the trunk joints are controlled to generate the angular momentum necessary to compensate for the deviation of the waist posture, which is used as the reference point for the motion coordinate system of the robot. Once the proposed control system was developed and simulated, we found that the hopping duration in the unconstrained state was extended. 相似文献
102.
A system procedure is proposed for a multi-robot rescue system that performs real-time exploration over disaster areas. Real-time exploration means that every robot exploring the area always has a communication path to human operators standing by at a base station and that the communication path is configured by ad hoc wireless networking. Real-time exploration is essential in multi-robot systems for USAR (urban search and rescue) because operators must communicate with every robot to support the victim detection process and ad hoc networking is suitable to configure a communication path among obstacles. The proposed system procedure consists of the autonomous classification of robots into search and relay types and behavior algorithms for each class of robot. Search robots explore the areas and relay robots act as relay terminals between search robots and the base station. The rule of the classification and the behavior algorithm refer to the forwarding table of each robot constructed for ad hoc networking. The table construction is based on DSDV (destination-sequenced distance vector) routing that informs each robot of its topological position in the network and other essentials. Computer simulations are executed with a specific exploration strategy of search robots. The results show that a multi-robot rescue system can perform real-time exploration with the proposed system procedure and reduce exploration time in comparison with the case where the proposed scheme is not adopted. 相似文献
103.
Yukao Tanaka Hidetoshi Nishigaito Hiroo Konishi Masashi Nishimura 《Electrical Engineering in Japan》2001,136(3):49-57
An advanced real‐time power system simulator consisting of a conventional real‐time analog simulator and a real‐time digital simulator has been developed. EMTP simulations were carried out to verify the advanced power system simulator concept and to evaluate the effects of various parameters. A prototype of the advanced power system simulator using the Bergeron method was tested. The test results confirmed the feasibility of the real‐time power system simulator. © 2001 Scripta Technica, Electr Eng Jpn, 136(3): 49–57, 2001 相似文献
104.
Masashi Totokawa Syuichi Yamashita Kenji Morikawa Yoshihito Mitsuoka Toshihiko Tani Hiroaki Makino 《International Journal of Applied Ceramic Technology》2009,6(2):195-204
The piezoresistive mechanisms of composite thick films based on RuO2 particles and both calcium-borosilicate and bismuth-borosilicate glass matrices were investigated by chemical and electrical microanalyses. The resistor based on bismuth-borosilicate glass showed higher sensitivity than that based on calcium-borosilicate glass. It was confirmed that the diffusion of ruthenium into glass affects the binding state of RuO2 at the interface of the glass. Furthermore, an intermediate resistive layer is detected around the RuO2 particle. These results suggest that the piezoresistive effect is related to a change in the electrical conductivity of the interfacial reaction layer caused by the diffusion of ruthenium into glass. 相似文献
105.
Jung Hyun Kong Masahiro Okumiya Yoshiki Tsunekawa Ky Youl Yun Sang Gweon Kim Masashi Yoshida 《Metallurgical and Materials Transactions A》2014,45(10):4443-4453
A great deal of research is being carried out on welding or bonding methods between iron and aluminum. However, it is not so easy to make Fe-Al bonding materials with both high strength and light weight. Recently, a new nitriding process has been proposed to produce aluminum nitride on an aluminum surface using a barrel. This study proposes a new concept in the production of a multilayer which has an AlN and Fe-Al intermetallic compound layer between the aluminum and steel using a barrel nitriding process. The bonding process was carried out from 893 K to 913 K (620 °C to 640 °C) for 18, 25.2, and 36 ks with Al2O3 powder and Al-Mg alloy powder. After the process, an aluminum nitride (AlN) layer and a Fe-Al intermetallic compound (Fe2Al5.4) layer were formed at the interface between the pure aluminum and SUS304 austenitic stainless steel. The thicknesses of the AlN layer and the intermetallic compound layer increased with increasing treatment temperature and time. The maximum hardnesses of the AlN layer and Fe2Al5.4 layers were found to be 377HV and 910HV, respectively, after barrel nitriding at 893 K (620 °C) for 18 ks. 相似文献
106.
Masashi Watanabe 《Polymer International》2007,56(10):1265-1271
The effect of electron acceptors as dopants on the bending electrostriction of polyurethane (PU) films was studied. The PU films (ca 0.3 mm thick) doped with 0.5 wt% 7,7,8,8‐tetracyanoquinodimethane (TCNQ) were bent by application of a 1 MV m?1 electric field. The bending deformation of the TCNQ‐doped film was more than 30 times greater than that of the undoped film. The current and the charge distribution in the films during the application of the field were also measured. Based on these measurements, the mechanism of the doping effect is discussed. Copyright © 2007 Society of Chemical Industry 相似文献
107.
Cooking up an interactive olfactory game display. 总被引:2,自引:0,他引:2
Takamichi Nakamoto Shigeki Otaguro Masashi Kinoshita Masahiko Nagahama Keita Ohinishi Taro Ishida 《Computer Graphics and Applications, IEEE》2008,28(1):75-78
It's long been possible to give users outside an actual environment that environment's visual and auditory information and thus contribute to establishing presence. However, we've yet to establish much presence when users require olfactory information - such as in environments focused on foods, flowers, perfumes, or, in some cases, more offensive smells. Recently, several VR researchers have become interested in olfaction and olfactory displays that present smells in virtual environments (VEs). In this article, we describe our interactive olfactory display. One of our development goals is to confirm the assumption that users' interactions with the system increases presence. Thus, we used our interactive olfactory display to develop a cooking game in collaboration with electronic engineers and artists. 相似文献
108.
109.
Masashi Takahashi Shin-Ichi Goto Kazuhisa Mori Izumi Mataga 《Frontiers of Materials Science in China》2008,2(4):437-440
The purpose of this study is to clarify the difference of histology and elemental composition of the cervical enamels among
the human permanent teeth. The reground surfaces at the cervical enamels of them were observed under scanning electron microscopy
(SEM). The contents of seven elements were analyzed quantitatively with electron probe microanalyzer (EPMA). The widths of
the rod sections at the cervical enamels were larger than those at the cuspal enamels. The rod sections at the mesial cervical
enamels in the incisors were more obscure and more decayed by acid solution than those in the premolars and molars. The calcium
and phosphorus contents of the cervical enamels were significantly lower than those of the cuspal enamels. The carbon content
of the cervical enamels was significantly higher than that of the cuspal enamels. The calcium and phosphorus contents of the
cervical enamels were the significantly highest in the premolars. The carbon and sodium contents of the cervical enamels were
significantly highest in the premolars. It is thought that the calcification level is lower, while the content of organic
matter is higher at the cervical enamels than those at the cuspal enamels. It is considered that the sodium causes high calcification. 相似文献
110.
Hajime Haneda Isao Sakaguchi Akio Watanabe Takamasa Ishigaki Junzo Tanaka 《Journal of Electroceramics》1999,4(1):41-48
18O diffusion coefficients were measured in zinc oxide ceramics using a secondary ion mass spectrometer. The results are interpreted as indicating extrinsic behavior. The values of the lattice diffusion coefficients with higher valence dopants compared with zinc ions are greater than lower valence dopant such as lithium ions. Using the data at deeper depth, the grain boundary diffusivity of oxide ions was also evaluated. Although the lattice diffusion coefficients varied by two orders of magnitude, the products of grain boundary width and grain boundary diffusion coefficient were less sensitive to the type of dopants. 相似文献