Propulsive force calculations in swimming frogs I. A momentum–impulse approach
نویسندگان
چکیده
منابع مشابه
Propulsive force calculations in swimming frogs. I. A momentum-impulse approach.
Frogs are animals that are capable of locomotion in two physically different media, aquatic and terrestrial. A comparison of the kinematics of swimming frogs in a previous study revealed a difference in propulsive impulse between jumping and swimming. To explore this difference further, we determined the instantaneous forces during propulsion in swimming using an impulse-momentum approach based...
متن کاملPropulsive force calculations in swimming frogs. II. Application of a vortex ring model to DPIV data.
Frogs propel themselves by kicking water backwards using a synchronised extension of their hind limbs and webbed feet. To understand this propulsion process, we quantified the water movements and displacements resulting from swimming in the green frog Rana esculenta, applying digital particle image velocimetry (DPIV) to the frog's wake. The wake showed two vortex rings left behind by the two fe...
متن کاملUnsteady flow field around a human hand and propulsive force in swimming.
Much effort has been undertaken for the estimation of propulsive force of swimmers in the front crawl. Estimation is typically based on steady flow theory: the so-called quasi-steady analysis. Flow fields around a swimmer, however, are extremely unsteady because the change direction of hand produces unsteady vortex motions. To evaluate the force correctly, it is necessary to know the unsteady p...
متن کاملDetermining propulsive force in front crawl swimming: a comparison of two methods.
To evaluate the propulsive forces in front crawl arm swimming, derived from a three-dimensional kinematic analysis, these values were compared with mean drag forces. The propulsive forces during front crawl swimming using the arms only were calculated using three-dimensional kinematic analysis combined with lift and drag coefficients obtained in fluid laboratories. Since, for any constant swimm...
متن کاملPropulsive impulse as a covarying performance measure in the comparison of the kinematics of swimming and jumping in frogs.
Animals have to modulate their locomotor behavior according to changes in external circumstances. The locomotor requirements are expected to be most extreme for species that move through different physical environments, such as water versus land. In this study, we examine the use of the propulsive impulse as a covariate in the comparison of the kinematics of locomotion of a semi-aquatic frog Ra...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Experimental Biology
سال: 2005
ISSN: 1477-9145,0022-0949
DOI: 10.1242/jeb.01509