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Dynamic Walking of a Legged Robot in Underwater Environments

Portilla, Saltarén, Espinosa, Barroso, Cely, Yakrangi
2019 Sensors  
In this research, the dynamic walking of a legged robot in underwater environments is proposed.  ...  The concept demonstration of a legged robot with hydraulic actuators is developed. Moreover, the control that was used is described and the hydrodynamic variables of the robot are determined.  ...  Conflicts of Interest: The authors declare no conflicts of interest.  ... 
doi:10.3390/s19163588 fatcat:3lpyqkmavvhsdixeodymscifqq

A model of neural control of the heart rate

Michael Rosenblum, Jürgen Kurths
1995 Physica A: Statistical Mechanics and its Applications  
Different known patterns of heart rate variability are observed, depending on the type of control and the parameter values.  ...  A simple model of heart rate regulation is proposed, using the assumption that the nervous system regulates the generation of pulses of the pacemaker.  ...  M.R. acknowleges financial support from A. von Humboldt Foundation.  ... 
doi:10.1016/0378-4371(95)00041-5 fatcat:oxtieojudjaqblgxceogv2q3rm

From cineradiography to biorobots: an approach for designing robots to emulate and study animal locomotion

K. Karakasiliotis, R. Thandiackal, K. Melo, T. Horvat, N. K. Mahabadi, S. Tsitkov, J. M. Cabelguen, A. J. Ijspeert
2016 Journal of the Royal Society Interface  
The robot closely matches the behaviour of the animal in terms of relative forward speeds and lateral displacements. Ground reaction forces during walking also resemble those of the animal.  ...  Pleurobot is a dynamically scaled amphibious salamander robot with a large number of actuated degrees of freedom (DOFs: 27 in total).  ...  We are grateful to Dr Martin Fischer at the University of Jena, Germany, for providing access to the cineradiography equipment and to Dr Nadja Schilling for helping with the experiments. Endnotes  ... 
doi:10.1098/rsif.2015.1089 pmid:27358276 pmcid:PMC4938076 fatcat:opq6yusuv5advgkindoiccsyjq

Dynamical disease: Identification, temporal aspects and treatment strategies of human illness

Jacques Bélair, Leon Glass, Uwe an der Heiden, John Milton
1995 Chaos  
This paper summarizes advances in the study of dynamical disease with emphasis on a NATO Advanced Research Worshop held in Mont Tremblant, Quebec, Canada in February 1994.  ...  Thus, there is a natural matching between the mathematical field of nonlinear dynamics and medicine.  ...  Collins and DeLuca 25 considered postural control during quiet standing from the point of view of a random walk.  ... 
doi:10.1063/1.166069 pmid:12780147 fatcat:se352xrq45bfjbd3vasprojfui

Realizing underactuated bipedal walking with torque controllers via the ideal model resolved motion method

Eric Cousineau, Aaron D. Ames
2015 2015 IEEE International Conference on Robotics and Automation (ICRA)  
dynamics is integrated forward from the actual state of the hardware to provide desired positions and velocity commands to a PD controller.  ...  This paper presents experimentally realized bipedal robotic walking using ideal torque controllers via a novel approach termed the ideal model resolved motion method (IM-RMM), where a system's ideal closed-loop  ...  ACKNOWLEDGMENT The authors want to thank SRI International for the design, development, and testing of DURUS, Dr.  ... 
doi:10.1109/icra.2015.7140004 dblp:conf/icra/CousineauA15 fatcat:sccd4bf5kng2ld64qonemlbhfy

Rhythm synchronization and chaotic modulation of coupled Van der Pol oscillators in a model for the heartbeat

Angela M. dos Santos, Sergio R. Lopes, R.L.Ricardo L. Viana
2004 Physica A: Statistical Mechanics and its Applications  
We also investigate the shadowing breakdown of numerically generated chaotic trajectories of the coupled oscillator system via unstable dimension variability in its chaotic invariant set.  ...  In order to warrant a robust operation, it is desirable that both units oscillate in a synchronized way, even though in the presence of external in uences or parameter mismatches which are unavoidable  ...  Moreover, the excitation of the atria and ventricles occurs with a time lag in the millisecond range.  ... 
doi:10.1016/j.physa.2004.02.058 fatcat:rppwhez4dnf3bggfwwzqqg3azq

Energy Efficiency of a Quadruped Robot with Neuro-Inspired Control in Complex Environments

Paolo Arena, Luca Patanè, Salvatore Taffara
2021 Energies  
This paper proposes an analysis of the energy efficiency of a small quadruped robotic structure, designed based on the MIT Mini Cheetah, controlled using a central pattern generator based on the FitzHugh–Nagumo  ...  In particular, simple control strategies impacting the leg trajectories are taken into account as the main factors affecting the energy efficiency in different terrain configurations.  ...  Data Availability Statement: The data presented in this study are available on request from the corresponding author. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/en14020433 fatcat:porpy3uuarhcdm3bf5x34y3q7u

Control Lyapunov Functions for Compliant Hybrid Zero Dynamic Walking [article]

Jenna Reher, Aaron D. Ames
2021 arXiv   pre-print
With the goal of achieving a variety of walking speeds in all directions, a library of compliant walking motions is compiled and then parameterized for efficient use within real-time controllers.  ...  A compliant model of Cassie is represented as a hybrid system to set the stage for a trajectory optimization framework.  ...  The authors would like to thank Claudia Kann for her help in the early discussions of the ID-CLF-QP approach, and Wen-Loong Ma and Noel Csomay-Shanklin for experimental assistance.  ... 
arXiv:2107.04241v1 fatcat:eyd6psedvzg25d7vrr7o6k3upy

Fractal Phenomena in Disordered Systems

R Orbach
1989 Annual Review of Materials Science  
This was achieved by balancing the short-range attractive van der Waals forces against the net repulsive electrostatic forces between the charged particles controlled by the counter-ion concentration in  ...  In model three, the particle is allowed to rotate as often as necessary until it finally reaches a local minimum.  ... 
doi:10.1146/ fatcat:mpuj6ewawrhjrm7goprgrftjay

Fractal Phenomena In Disordered Systems

R Orbach
1989 Annual Review of Materials Science  
This was achieved by balancing the short-range attractive van der Waals forces against the net repulsive electrostatic forces between the charged particles controlled by the counter-ion concentration in  ...  In model three, the particle is allowed to rotate as often as necessary until it finally reaches a local minimum.  ... 
doi:10.1146/annurev.matsci.19.1.497 fatcat:z2vebektlrhafk6mwirlhdpri4

Combining Trajectory Optimization, Supervised Machine Learning, and Model Structure for Mitigating the Curse of Dimensionality in the Control of Bipedal Robots [article]

Xingye Da, Jessy Grizzle
2017 arXiv   pre-print
To overcome the obstructions imposed by high-dimensional bipedal models, we embed a stable walking motion in an attractive low-dimensional surface of the system's state space.  ...  We then use the special structure of mechanical models associated with bipedal robots to embed the low-dimensional model in the original model in such a manner that the desired walking motions are locally  ...  Acknowledgements The optimization and gait generation for the 3D walking and  ... 
arXiv:1711.02223v1 fatcat:za63vkgejfhajost5mfdwxdfny

Modular power plants, based on gas turbine: the way forward for the nuclear energy development
Модульні енергетичні установки на основі газової турбіни: перспективний шлях розвитку ядерної енергетики

O.A. Mekh, Dobrov Institute for Scientific and Technological Potential and Science History Studies of NAS of Ukraine, Kyiv, S.G. Boublyk, Dobrov Institute for Scientific and Technological Potential and Science History Studies of NAS of Ukraine, Kyiv
2019 Visnik Nacional noi academii nauk Ukrai ni  
The second half of the book presents the main effects of synchronization in a rigorous and systematic manner, describing both classical results on the synchronization of periodic oscillators and recent  ...  Systems as diverse as clocks, singing crickets, cardiac pacemakers, firing neurons, and applauding audiences exhibit a tendency to operate in synchrony.  ...  A chaotic model must have at least three dimensions, i.e., the state of the oscillator must be described by at least three coordinates.  ... 
doi:10.15407/visn2019.07.064 fatcat:dj4ndsex5ffhxhfd6bnrjs6l6q

A review on locomotion robophysics: the study of movement at the intersection of robotics, soft matter and dynamical systems

Jeffrey Aguilar, Tingnan Zhang, Feifei Qian, Mark Kingsbury, Benjamin McInroe, Nicole Mazouchova, Chen Li, Ryan Maladen, Chaohui Gong, Matt Travers, Ross L Hatton, Howie Choset (+2 others)
2016 Reports on progress in physics (Print)  
In this review we argue for the creation of a physics of moving systems -- a locomotion "robophysics" -- which we define as the pursuit of the discovery of principles of self generated motion.  ...  The essential idea is that we must complement study of complex robots in complex situations with systematic study of simplified robophysical devices in controlled laboratory settings and simplified theoretical  ...  Bipedal walking robots tend to perform better in simpler hard ground scenarios than in the above-mentioned unconstrained obstacle-laden environments, such as with the ATRIAS (Assume The Robot Is A Sphere  ... 
doi:10.1088/0034-4885/79/11/110001 pmid:27652614 fatcat:qhn6swo7gvaqndqxbdxjq3vlny

Heart rate variability study-using phase response curve

Pei Z. Zhang, Stanley S. Reisman, Walter N. Tapp
1992 Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society  
Each original is also photographed in one exposure and is included in reduced form at the back of the book.  ...  Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer.  ...  the oscillation as shown in Figure 3.2.1 d.  ... 
doi:10.1109/iembs.1992.5761114 fatcat:gr37hme7sjcw7oc5gzbwlyrf7e

Bipedal Hopping: Reduced-order Model Embedding via Optimization-based Control [article]

Xiaobin Xiong, Aaron Ames
2018 arXiv   pre-print
This paper presents the design and validation of controlling hopping on the 3D bipedal robot Cassie. A spring-mass model is identified from the kinematics and compliance of the robot.  ...  The leg length trajectories are utilized as desired outputs to synthesize a control Lyapunov function based quadratic program (CLF-QP).  ...  The future work will be devoted to extending the approach to create different dynamic behaviors on bipedal robots, likely including reduced-order modeling in two or three dimensions for walking and running  ... 
arXiv:1807.08037v2 fatcat:nucoibu6q5gvxiw6bsy2zkfgkq
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