Search results for "Cinemàtica"
showing 6 items of 6 documents
Optimization of 3-DOF Parallel Motion Devices for Low-Cost Vehicle Simulators
2017
Motion generation systems are becoming increasingly important in certain Virtual Reality (VR) applications, such as vehicle simulators. This paper deals with the analysis of the Inverse Kinematics (IK) and the reachable workspace of a three-degrees-of-freedom (3-DOF) parallel manipulator, proposing different transformations and optimizations in order to simplify its use with Motion Cueing Algorithms (MCA) for self-motion generation in VR simulators. The proposed analysis and improvements are performed on a 3-DOF heave-pitch-roll manipulator with rotational motors, commonly used for low-cost motion-based commercial simulators. The analysis has been empirically validated against a real 3-DOF …
Smooth Three-Dimensional Route Planning for Fixed-Wing Unmanned Aerial Vehicles With Double Continuous Curvature
2022
This paper presents a smooth flight path planner for maneuvering in a 3D Euclidean space, which is based on two new space curves. The first one is called 'Elementary Clothoid-based 3D Curve (ECb3D)', which is built by concatenating two symmetric Clothoid-based 3D Curves (Cb3D). The combination of these curves allows to reach an arbitrary orientation in 3D Euclidean space. This new curve allows to generate continuous curvature and torsion profiles that start and finish with a null value, which means that they can be concatenated with other curves, such as straight segments, without generating discontinuities on those variables. The second curve is called 'Double Continuous Curvature 3D Curve…
Evaluación de parámetros biomecánicos del lanzamiento de jabalina en lanzadores de diferente nivel de rendimiento
2000
Mediante análisis cinemático y utilizando como muestra a lanzadores agrupados en función de
 la marca conseguida (grupo internacional: atletas con marca superior a los 80 metros; y grupo
 nacional: atletas con marca inferior a 80 metros) el objetivo del estudio se centró en determinar si
 alguno de los parámetros utilizados para evaluar la eficacia del gesto establece diferencias entre
 uno y otro grupo de lanzadores.
 Los resultados muestran que algunos de dichos parámetros cinemáticos ayudan a establecer los
 márgenes para la pertenencia a los. Del total de las 41 variables contrastadas, sólo 8 de ellas
 establecían diferencias significativas entre grupo…
Validity and Reliability of the Leomo Motion-Tracking Device Based on Inertial Measurement Unit with an Optoelectronic Camera System for Cycling Peda…
2022
Background: The use of inertial measurement sensors (IMUs), in the search for a more ecological measure, is spreading among sports professionals with the aim of improving the sports performance of cyclists. The kinematic evaluation using the Leomo system (TYPE-R, Leomo, Boulder, CO, USA) has become popular. Purpose: The present study aimed to evaluate the reliability and validity of the Leomo system by measuring the angular kinematics of the lower extremities in the sagittal plane during pedaling at different intensities compared to a gold-standard motion capture camera system (OptiTrack, Natural Point, Inc., Corvallis, OR, USA). Methods: Twenty-four elite cyclists recruited from national a…
A kinematic method to obtain conformal factors
2000
Radial conformal motions are considered in conformally flat space-times and their properties are used to obtain conformal factors. The geodesic case leads directly to the conformal factor of Robertson-Walker universes. General cases admitting homogeneous expansion or orthogonal hypersurfaces of constant curvature are analyzed separately. When the two conditions above are considered together a subfamily of the Stephani perfect fluid solutions, with acceleration Fermi-Walker propagated along the flow of the fluid, follows. The corresponding conformal factors are calculated and contrasted with those associated with Robertson-Walker space-times.
Effect of the upper material of running shoes on muscle mechanical power transfer on lower limbs
2022
This study focuses on determining the effects of the upper material of running shoes on the mechanical power flows of the muscles of the lower limbs during the support phase of running. Two models of running shoes—differentiated only by the upper structure and material—have been used, being randomly assigned to 19 participants. Five measurements of each participant per shoe model were obtained at 3.3 m·s−1 to perform inverse dynamic analysis with the data obtained. Statistically significant differences have been found between the two models for the muscle power flow variables in the ankle, knee and hip joints, as well as at the ends of adjacent segments. The KNIT-upper model (model 2) pres…