Search results for " gear"
showing 5 items of 15 documents
Training-induced increase in Achilles tendon stiffness affects tendon strain pattern during running
2019
Background During the stance phase of running, the elasticity of the Achilles tendon enables the utilisation of elastic energy and allows beneficial contractile conditions for the triceps surae muscles. However, the effect of changes in tendon mechanical properties induced by chronic loading is still poorly understood. We tested the hypothesis that a training-induced increase in Achilles tendon stiffness would result in reduced tendon strain during the stance phase of running, which would reduce fascicle strains in the triceps surae muscles, particularly in the mono-articular soleus. Methods Eleven subjects were assigned to a training group performing isometric single-leg plantarflexion co…
Narratiivisten videopelien kehittyminen
2012
Tässä tutkielmassa analysoidaan narratiivisten videopelien kehittymistä ja sitä, miten samanaikainen teknologian kehittyminen on siihen vaikuttanut. Tutkimus on luonteeltaan kvalitatiivinen ja se pyrkii kuvaamaan mahdollisimman laajasti sitä, mikä on muuttunut pelien narratiivisessa sisällössä, immersiossa ja henkilöhahmoissa. Tutkielmassa keskitytään käsittelemään kolmea narratiivista pelisarjaa: Fallouttia, Final Fantasya ja Metal Gearia. Pelisarjojen muutoksia ja niiden syitä tarkastellaan muun muassa moniulotteisen typologian ja erilaisten narratiivien avaamiseen käytettyjen termien ja teorioiden avulla. Analyysi osoitti, että narratiiviset pelit ovat muuttuneet teknologian kehittyessä …
Design of a Hybrid Electric Power-Split Transmission for Braking Energy Recovery in a Drilling Rig
2022
Despite the promising potential of the hybrid electric power-split layout, its broader market penetration is prevented by the large number of feasible solutions and the constructive complexity, which overcomplicate the design process. Moreover, due to the lack of relevant literature references, the power-split transmissions design is even more difficult if concerning applications outside the automotive and agricultural sectors. In this paper, a general parametric model already available in the literature to design a single-mode power-split transmission with up to two planetary gear sets and six ordinary gear sets was applied to hybridize an oil drilling rig to recover energy braking during …
Study and Simulation of Helicopter Gearboxes Noise
2010
International audience; Main gearbox is one of the main noise sources in helicopter cabin. In order to improve the comfort of customers and reduce the health impact, acoustic and vibration mechanisms of gearboxes have to be understood and simulated during development phases. Thus, we first present the global methodology chosen to compute main gearboxes noise in helicopter cabins. Secondly, we described the way we compute mechanical excitation sources induced from gear mesh, static transmission error and meshing stiffness. Depending on the type of gear, we compute those using either analytical specially developed code or EC codes. Thirdly, we propose a modeling to compute dynamic loads on be…
A Note on the Mechanics of Ancient Gear Systems
2011
This paper deals with the mechanical behavior of the gearwheels of the antiquity, which were generally characterized by triangular shaping of the teeth. The engagement of the conjugate profiles is analyzed in detail, calculating the temporal variation of the speed ratio due to the back and forth shifting of the relative instant center. The admissibility of the points of the theoretical contact path is carefully checked, estimating also the magnitude of the successive tooth collisions and ascertaining the energy losses arising from the particular nature of the coupling. Some very interesting results are that only one couple of teeth turns out to be active at each time instant and that the re…