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Design and control of compliant tensegrity robots through simulation and hardware validation 总被引:1,自引:0,他引:1
Ken Caluwaerts Jérémie Despraz At?l I??en Andrew P. Sabelhaus Jonathan Bruce Benjamin Schrauwen Vytas SunSpiral 《Journal of the Royal Society Interface》2014,11(98)
To better understand the role of tensegrity structures in biological systems and their application to robotics, the Dynamic Tensegrity Robotics Lab at NASA Ames Research Center, Moffett Field, CA, USA, has developed and validated two software environments for the analysis, simulation and design of tensegrity robots. These tools, along with new control methodologies and the modular hardware components developed to validate them, are presented as a system for the design of actuated tensegrity structures. As evidenced from their appearance in many biological systems, tensegrity (‘tensile–integrity’) structures have unique physical properties that make them ideal for interaction with uncertain environments. Yet, these characteristics make design and control of bioinspired tensegrity robots extremely challenging. This work presents the progress our tools have made in tackling the design and control challenges of spherical tensegrity structures. We focus on this shape since it lends itself to rolling locomotion. The results of our analyses include multiple novel control approaches for mobility and terrain interaction of spherical tensegrity structures that have been tested in simulation. A hardware prototype of a spherical six-bar tensegrity, the Reservoir Compliant Tensegrity Robot, is used to empirically validate the accuracy of simulation. 相似文献
2.
Mohammed Smadi Terence D. Todd Vytas Kezys Vahid Azhari Dongmei Zhao 《Wireless Networks》2008,14(6):815-829
In this paper we consider vertical handoff for enterprise-based dual-mode (DM) cellular/WLAN handsets. When the handset roams
out of WLAN coverage, the DM's cellular interface is used to maintain the call by anchoring it through an enterprise PSTN
gateway/PBX. Soft handoff can be achieved in this case if the gateway supports basic conference bridging, since a new leg
of the call can be established to the conference bridge while the existing media stream path is active. Unfortunately this
requires that all intra-enterprise calls be routed through the gateway when the call is established. In this paper we consider
a SIP based architecture to perform conferenced dual-mode handoff and propose a much more scalable mechanism for short-delay
environments, whereby active calls are handed off into the conference bridge prior to the initiation of the vertical handoff.
Results are presented which are taken from a dual-mode handset testbed, from analytic models, and from simulations which characterize
the scalability of the proposed mechanism.
Mohammed Smadi received the B.Eng and Mgmt and M.A.Sc degrees in Computer Engineering from McMaster University in Hamilton, Ontario, Canada.
Mohammed received an NSERC doctoral award in 2005 and is currently a Ph.D. student at the Wireless Networking Group at McMaster
University.
Terence D. Todd received the B.A.Sc, M.A.Sc and Ph.D. degrees in Electrical Engineering from the University of Waterloo, Waterloo, Ontario,
Canada. While at Waterloo he spent 3 years as a Research Associate with the Computer Communications Networks Group (CCNG).
He is currently a Professor of Electrical and Computer Engineering at McMaster University in Hamilton, Ontario, Canada.
Professor Todd spent 1991 on research leave in the Distributed Systems Research Department at AT&T Bell Laboratories in Murray
Hill, NJ. He also spent 1998 on research leave at The Olivetti and Oracle Research Laboratory in Cambridge, England. While
at ORL he worked on the piconet project which was an early embedded wireless network testbed.
Dr. Todd’s research interests include metropolitan/local area networks, wireless communications and the performance analysis
of computer communication networks and systems. He is a past Editor of the IEEE/ACM Transactions on Networking and currently
holds the NSERC/RIM/CITO Chair on Pico-Cellular Wireless Internet Access Networks.
Dr. Todd is a Professional Engineer in the province of Ontario and a member of the IEEE.
Vytas Kezys was born in Hamilton, Canada in 1957. He received the B.Eng. degree in Electrical Engineering from McMaster University, Canada,
in 1979.
From 1979 to 1998, Mr. Kezys was involved in radar and communications research as Principal Research Engineer at the Communications
Research Laboratory, McMaster University. While at McMaster, his research activities included array signal processing for
low-angle tracking radar, radar signal processing, and smart antennas for wireless communications. Mr. Kezys was founder and
President of TalariCom Inc., a start-up company that developed cost effective smart antenna technologies for broadband wireless
access applications.
Currently, Mr. Kezys is Director of Advanced Products at Research in Motion in Waterloo, Canada.
Vahid S. Azhari received his B.S. and M.S. from the Department of Electrical and Computer Engineering, IUST and University of Tehran, Iran,
in 2000 and 2003 respectively. His M.S. research focused on designing scheduling algorithms for switch fabrics. He also worked
for two years for the Iranian Telecommunication Research Centre on developing software for SDH switches. He is currently pursuing
his Ph.D. degree at the Wireless Networking Laboratory, McMaster University, Canada. His main area of research includes handoff
management in integrated wireless networks, WLAN deployment techniques, and wireless mesh networks.
Dongmei Zhao received the Ph.D. degree in Electrical and Computer Engineering from the University of Waterloo, Waterloo, Ontario, Canada
in June 2002. Since July 2002 she has been with the Department of Electrical and Computer Engineering, McMaster University,
Hamilton, Ontario, Canada where she is an assistant professor. Dr. Zhao’s research interests include modeling and performance
analysis, quality-of-service provisioning, access control and admission control in wireless cellular networks and integrated
cellular and ad hoc networks. Dr. Zhao is a member of the IEEE. 相似文献
3.
Sergei Evteev Dmitry Nilov Aleksandra Polenova Vytas vedas 《International journal of molecular sciences》2021,22(23)
The growing resistance of the influenza virus to widely used competitive neuraminidase inhibitors occupying the active site of the enzyme requires the development of bifunctional compounds that can simultaneously interact with other regulatory sites on the protein surface. When developing such an inhibitor and combining structural fragments that could be located in the sialic acid cavity of the active site and the adjacent 430-cavity, it is necessary to select a suitable linker not only for connecting the fragments, but also to ensure effective interactions with the unique arginine triad Arg118-Arg292-Arg371 of neuraminidase. Using molecular modeling, we have demonstrated the usefulness of the sulfonamide group in the linker design and the potential advantage of this functional group over other isosteric analogues. 相似文献
4.
We have determined the particle size distribution profiles of octane-terminated silicon nanoparticle suspensions, produced using the sonication of electrochemically etched Si wafers. Small-angle neutron scattering data was analyzed separately in high (0.4?nm(-1)
相似文献
5.
Mark A. Bieniawski Kofi L. P. Stevens Christopher M. Witham Robert F. L. Steuart Vytas A. Bankaitis Carl J. Mousley 《International journal of molecular sciences》2022,23(20)
Endoplasmic reticulum (ER) function is dedicated to multiple essential processes in eukaryotes, including the processing of secretory proteins and the biogenesis of most membrane lipids. These roles implicate a heavy burden to the organelle, and it is thus prone to fluctuations in the homeostasis of molecules which govern these processes. The unfolded protein response (UPR) is a general ER stress response tasked with maintaining the ER for optimal function, mediated by the master activator Ire1. Ire1 is an ER transmembrane protein that initiates the UPR, forming characteristic oligomers in response to irregularities in luminal protein folding and in the membrane lipid environment. The role of lipids in regulating the UPR remains relatively obscure; however, recent research has revealed a potent role for sphingolipids in its activity. Here, we identify a major role for the oxysterol-binding protein Kes1, whose activity is of consequence to the sphingolipid profile in cells resulting in an inhibition of UPR activity. Using an mCherry-tagged derivative of Ire1, we observe that this occurs due to inhibition of Ire1 to form oligomers. Furthermore, we identify that a sphingolipid presence is required for Ire1 activity, and that specific sphingolipid profiles are of major consequence to Ire1 function. In addition, we highlight cases where Ire1 oligomerization is absent despite an active UPR, revealing a potential mechanism for UPR induction where Ire1 oligomerization is not necessary. This work provides a basis for the role of sphingolipids in controlling the UPR, where their metabolism harbors a crucial role in regulating its onset. 相似文献
6.
Suplatov Dmitry Shegay Maxim Sharapova Yana Timokhin Ivan Popova Nina Voevodin Vladimir Švedas Vytas 《The Journal of supercomputing》2021,77(11):12382-12398
The Journal of Supercomputing - The field of biology is producing data faster than ever before. To approach its analysis efficiently, one can take advantage of a systematic symbiosis between the... 相似文献
7.
Vincent L. Vilker Vytas Reipa Martin Mayhew Marcia J. Holden 《Journal of the American Oil Chemists' Society》1999,76(11):1283-1289
Biocatalysis using oxygenase or desaturase enzymes has the potential to add value to native fats and oils by adding oxygen,
hydroxyl groups, or double bonds to create regio- and/or stereospecific products. These enzymes are a subset of the large
class of oxidoreductase enzymes (from EC subgroups 1.13 and 1.14) involved with biological oxidation and reduction. In vitro biocatalytic processing using these enzymes is hampered by the high cost of the stoichiometric cofactors. This article reviews
recent progress in developing in vitro redox enzyme biocatalysis for commercial-scale syntheses. Coenzyme recycling and electrochemical redox cycling as methods
for cofactor regeneration are described and commercial applications indicated. Direct charge transfer without use of mediators
is described as the cleanest way of introducing the reducing power into the catalytic cycle. Our electrochemically driven
cytochrome P450cam bioreactor is discussed as an example of direct charge transfer to a redox protein. Site-directed mutagenesis in the active
site of the P450cam monooxygenase greatly improved performance for the conversion of the nonnative substrate, styrene to styrene oxide. This
epoxidation reaction was also shown to give a single product (styrene oxide) in the bioelectrochemical reactor when the diatomic
oxygen co-substrate was managed properly.
Certain commercial equipment, instruments, and materials are identified in this paper to specify adequately the experimental
procedure. In no case does such identification imply recommendation or endorsement by the National Institute of Standards
and Technology nor does it imply that the material or equipment is necessarily the best available for the purpose. 相似文献
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