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Evaluating the Effect of a Flexible Spine on the Evolution of Quadrupedal Gaits

Jared M. Moore, Craig P. McGowan, Philip K. McKinley
2015 07/20/2015-07/24/2015  
In this paper, we incorporate passive flexibility into the spine of a quadruped animat and employ computational evolution to generate gaits.  ...  Moreover, evolving the degree of spine flexibility along with artificial neural network controllers produces the highest performing solutions.  ...  Clark and gratefully acknowledge the BEACON Center for the Study of Evolution in Action, which directly supported this study and fosters an environment for interdisciplinary collaboration.  ... 
doi:10.7551/978-0-262-33027-5-ch035 dblp:conf/ecal/MooreMM15 fatcat:3wx7ajmnozhf3dtg3ibvftw7ja

Editorial: Computational modeling and simulation of quadrupedal animal movement

Gina Bertocci, John R. Hutchinson, Denis J. Marcellin-Little, Marcus G. Pandy
2022 Frontiers in Bioengineering and Biotechnology  
Additionally, the predictive capabilities of validated models can answer "what if" questions, and through sensitivity analysis can determine the influence of parameters on outcomes.  ...  In this Research Topic, researchers from the fields of bioengineering, robotics, mathematics, veterinary medicine, comparative biology and zoology, and kinesiology have advanced our understanding of quadrupedal  ...  The number of legs used to propel the body during locomotion has a decisive effect on the motion of the center of mass and gait stability.  ... 
doi:10.3389/fbioe.2022.943553 pmid:35928957 pmcid:PMC9344051 doaj:a4294b50124e49b499f7f494232dee3b fatcat:pwb7lcpjfzg7jcuvwjfowhyy34

Lateral bending of the lumbar spine during quadrupedalism in strepsirhines

Liza J. Shapiro, Brigitte Demes, Jennifer Cooper
2001 Journal of Human Evolution  
N. pygmaeus and L. tardigradus, to David Raichlen for helpful discussion on an earlier version of the manuscript, and to the reviewers, whose comments improved the paper.  ...  Acknowledgements The authors thank the staff of the Duke University Primate Center for permission to videotape the animals, and for technical assistance.  ...  This is surprising, considering the fact that one of the key innovations in the evolution of mammalian locomotion was the shift to an emphasis on sagittal, rather than lateral, movements of the spine  ... 
doi:10.1006/jhev.2000.0454 pmid:11180987 fatcat:lavapry3f5df3mexszrjhavmj4

Developing an embodied gait on a compliant quadrupedal robot

Jonas Degrave, Ken Caluwaerts, Joni Dambre, Francis Wyffels
2015 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)  
The morphology of quadrupedal robots has previously been used for sensing and for control of a compliant spine, but never for gait generation.  ...  We believe this method can provide a very useful tool for transferring knowledge from open loop to closed loop control on compliant robots.  ...  In Fig. 5 we plot the evolution of the MSE over time for different optimizations, filtered by a moving average with a time window of one gait period.  ... 
doi:10.1109/iros.2015.7354014 dblp:conf/iros/DegraveCDW15 fatcat:vc6uuebtuzf4jctln2kqkmof7u

Quadrupedal bounding with a segmented flexible torso: passive stability and feedback control

Qu Cao, Ioannis Poulakakis
2013 Bioinspiration & Biomimetics  
In this paper, the implications of torso flexibility on the dynamics of quadrupedal running are examined in a template setting.  ...  of torso flexibility via a minimum number of variables and parameters.  ...  Conclusion In this paper, the effects of torso flexibility on quadrupedal running with a bounding gait is studied in a template setting.  ... 
doi:10.1088/1748-3182/8/4/046007 pmid:24166806 fatcat:mq76b7fqwrbihmmlv4xad6sm7u

Quadrupedal locomotor simulation: producing more realistic gaits using dual-objective optimization

William Irvin Sellers, Eishi Hirasaki
2018 Royal Society Open Science  
It is apparent that adding a lateral stability criterion has an important effect on the footfall phase relationship, suggesting that lateral stability may be one of the key drivers behind the observed  ...  In this paper, we explore the effects of requiring adequate lateral stability and show how this increases both energetic cost and the realism of the generated walking gait in a high biofidelity chimpanzee  ...  The Centre is coordinated by the Universities of Leeds and Manchester.  ... 
doi:10.1098/rsos.171836 pmid:29657790 pmcid:PMC5882714 fatcat:3r6wtutfuzb2plf5pyyzbmkq6m

Exploring Diagonal Gait Using a Forward Dynamic Three-Dimensional Chimpanzee Simulation

W.I. Sellers, L. Margetts, K.T. Bates, A.T. Chamberlain
2013 Folia primatologica  
This suggests that the choice of diagonal walking gaits in chimpanzees is not a simple mechanical phenomenon and that diagonal walking gaits in primates are selected for by multiple factors.  ...  An alternative approach is to produce biologically realistic computer simulations of primate gait that enable the constraints of biomechanical loading and the energetics of different modes of locomotion  ...  Acknowledgements This work was funded by NERC and the Leverhulme Trust.  ... 
doi:10.1159/000351562 pmid:23867835 fatcat:rpfuh2p3gzel7dxenco7qvlds4

Etiology of lumbar lordosis and its pathophysiology: a review of the evolution of lumbar lordosis, and the mechanics and biology of lumbar degeneration

Carolyn J. Sparrey, Jeannie F. Bailey, Michael Safaee, Aaron J. Clark, Virginie Lafage, Frank Schwab, Justin S. Smith, Christopher P. Ames
2014 Neurosurgical Focus  
However, surgical management of postural deformity has focused on restoring posture at the expense of flexibility.  ...  Studies of fossils of human lineage demonstrate a convergence on the degree of lumbar lordosis and the number of lumbar vertebrae in modern Homo sapiens.  ...  Understanding the influence of lumbar lordosis and lumbar flexibility on human activities is critical for evaluating how to best balance the needs of a patient when determining the most effective approach  ... 
doi:10.3171/2014.1.focus13551 pmid:24785474 fatcat:zom4y42kyng2zccggepooi25hu

Assessment of Gait Therapy Effectiveness in Patients with Parkinson's Disease on the Basis of Three-Dimensional Movement Analysis

Elżbieta Mirek, Jadwiga Lubomira Kubica, Jadwiga Szymura, Szymon Pasiut, Monika Rudzińska, Wiesław Chwała
2016 Frontiers in Neurology  
Objective: The aim of this study was to assess the effect of physical exercise on gait pattern disorders, based on three-dimensional gait analysis in the sagittal plane in a group of people with Parkinson's  ...  of a body; MA, most affected side of a body; Norm, angular variation observed during physiological gait in the control group; normalized, mean normalized time values (% cycle of gait). 2 Mirek et al.  ...  of a body; MA, most affected side of a body; Norm, angular variation observed during physiological gait in the control group; normalized, mean normalized time values (% cycle of gait).  ... 
doi:10.3389/fneur.2016.00102 pmid:27445968 pmcid:PMC4921998 fatcat:m3ordp4wxfc7bg7hrjxpjf7c2q

Locomotion skills for simulated quadrupeds

Stelian Coros, Andrej Karpathy, Ben Jones, Lionel Reveret, Michiel van de Panne
2011 ACM Transactions on Graphics  
The controllers use a representation based on gait graphs, a dual leg frame model, a flexible spine model, and the extensive use of internal virtual forces applied via the Jacobian transpose.  ...  The resulting gaits are evaluated for robustness with respect to push disturbances and the traversal of variable terrain.  ...  Acknowledgements: We thank the anonymous reviewers for their suggestions for improving the paper. This work was supported by NSERC and GRAND.  ... 
doi:10.1145/2010324.1964954 fatcat:afipxe5kvveinfjfcutk4bai6y

Locomotion skills for simulated quadrupeds

Stelian Coros, Andrej Karpathy, Ben Jones, Lionel Reveret, Michiel van de Panne
2011 ACM SIGGRAPH 2011 papers on - SIGGRAPH '11  
The controllers use a representation based on gait graphs, a dual leg frame model, a flexible spine model, and the extensive use of internal virtual forces applied via the Jacobian transpose.  ...  The resulting gaits are evaluated for robustness with respect to push disturbances and the traversal of variable terrain.  ...  Acknowledgements: We thank the anonymous reviewers for their suggestions for improving the paper. This work was supported by NSERC and GRAND.  ... 
doi:10.1145/1964921.1964954 fatcat:ikgjzg5g4fcdfk6qmdv37ggiru

Ticks, Hair Loss, and Non-Clinging Babies: A Novel Tick-Based Hypothesis for the Evolutionary Divergence of Humans and Chimpanzees

Jeffrey G. Brown
2021 Life  
Human straight-legged bipedalism represents one of the earliest events in the evolutionary split between humans (Homo spp.) and chimpanzees (Pan spp.), although its selective basis is a mystery.  ...  The aim of this review is to propose and evaluate a novel tick-based evolutionary hypothesis wherein forest fragmentation in hominin paleoenvironments created conditions that were favourable for tick proliferation  ...  Anasu for their helpful discussions and review of the manuscript, as well as the editors and anonymous reviewers of earlier submissions, whose insightful comments greatly improved this paper.  ... 
doi:10.3390/life11050435 pmid:34066043 fatcat:eqxtn6jocnfaxhy3gx3rdpvx6i

Influence of Compliant Joints in Four-Legged Robots

Francesco Tracuzzi Spadaro, Giovanni Gerardo Muscolo
2020 Frontiers in Mechanical Engineering  
In this paper, we analyzed the behavior of a four-legged robot constituted by one active DOF in each leg (using commercial servomotors) and one passive DOF in each knee and in the spine (using springs)  ...  Legged animals are capable of rapid movements, are efficient from the energy point of view, and are able to adapt their gaits to environmental conditions.  ...  ACKNOWLEDGMENTS Many thanks to Politecnico di Torino for a Starting Grant for Assistant Professorship.  ... 
doi:10.3389/fmech.2020.00016 fatcat:4qowprhwh5fgxicqag6eixmvvm

Muscle mechanical advantage of human walking and running: implications for energy cost

Andrew A. Biewener, Claire T. Farley, Thomas J. Roberts, Marco Temaner
2004 Journal of applied physiology  
Muscular forces generated during locomotion depend on an animal's speed, gait, and size and underlie the energy demand to power locomotion.  ...  Changes in limb posture affect muscle forces by altering the mechanical advantage of the ground reaction force (R) and therefore the effective mechanical advantage (EMA ϭ r/R, where r is the muscle mechanical  ...  Richard Taylor, who inspired us and contributed importantly to earlier phases of the study but died before its completion. We also thank F. A.  ... 
doi:10.1152/japplphysiol.00003.2004 pmid:15258124 fatcat:f3jgz42cmram3kzrtsvf34iffu

The impact of pelvic lateral rotation on hindlimb kinematics and stride length in the red-legged running frog, Kassina maculata

Amber J. Collings, Laura B. Porro, Cameron Hill, Christopher T. Richards
2019 Royal Society Open Science  
All frogs used a walking gait (duty factor greater than 0.5) despite travelling over a range of speeds (0.04-0.23 m s-1).  ...  The pelvis itself, on average, underwent an angular excursion of 12.71° (±4.39°) with respect to the body midline during lateral rotation.  ...  Many thanks go to Alastair Wallis, Dale McCarthy, Michael Murphy and David Lathlean for the care of the research animals.  ... 
doi:10.1098/rsos.190060 pmid:31218049 pmcid:PMC6549954 fatcat:p2txgor33zbpbgzdiz3rsel4ri
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