Motion control

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Dynamics and motion control of Underwater remotely operated vehicles and highly flexible elastic rods

Dynamics and motion control of Underwater remotely operated vehicles and highly flexible elastic rods

This thesis develops analytical- and numerical-oriented tools for the dynamic analysis and motion control of ROVs, using an integrated approach where hydrodynamics, control, and cable effects are considered. These tools facilitate the analysis, design, and operation of ROV systems and are aimed at answering questions about their motion feasibility. They are grounded on available theory to model the ROV and cable, design of feedback control, and thrust allocation. Subsequently, this work contributes means to study the hydrodynamics of an ROV and develops a framework where hydrodynamics and other motion-relevant systems can be integrated and evaluated. For studying hydrodynamics, the manoeuvring behaviour of ROVs is approached by using time-domain simulation (TDS) and computational fluid dynamics (CFD). In this approach, viscous-flow computations are used to gather data about the hydrodynamic forces and moments that act on an ROV at certain flow conditions, and from that data a simplified meta-model is assembled to be used in time-domain simulations for manoeuvring, control, and motion feasibility analyses. For integrated motion feasibility studies, the concept of dynamic positioning capability (DPCap) for ROVs is proposed. The idea of DPCap was first introduced for surface vessels that include a dynamic positioning (DP) system, and in this work it is extended to ROVs. DPCap assesses whether craft are able to withstand environmental and operational loads, while keeping a desired position or path. This allows one to determine whether the system will be able to operate or not at certain conditions and quantify the level of motion capability. Through these approaches, this work delivers a framework to answer questions about ROV motion feasibility joining vehicle dynamics, hydrodynamics, cable mechanics, and control, and that intends to be useful at different stages of an ROV’s life-cycle.

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Desarrollo de practicas avanzadas para Motion Control con Kinetix 2000

Desarrollo de practicas avanzadas para Motion Control con Kinetix 2000

Hoy en día la tendencia actual de la industria, es sustituir las tecnologías que utilizan partes mecánicas en movimiento como: levas, cadenas, bandas, cajas de engranes, entre otras, debido a sus altos costo de mantenimiento, difícil diseño, construcción, durabilidad (desgaste del material), por equipos electrónicos que realicen las mismas funciones, con mejor desempeño, mayor fiabilidad, fácil detección y corrección de errores así como el diseño del perfil de movimiento y menor costo, por lo que los alumnos de la carrera de ICA, requieren al egresar contar con conocimientos y habilidades sobre las nuevas tecnologías que demanda la industria en el campo laboral, es por ello que se requiere que el alumno conozca sobre Motion Control y sus funciones avanzadas.

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Advanced Motion Control Systems for Underwater Robotic Vehicles

Advanced Motion Control Systems for Underwater Robotic Vehicles

With the validation of the VBS and VPS, all motion components of the UX-1 under- water vehicle are integrated and fully functional. Subsequently, exploration missions of the Kaatiala, Idrija, and Urgeiri¸ca shafts and tunnels are performed to gather scientific instrumentation measurements (i.e., Multispectral Camera Unit, Pressure Sensor, pH Sensor, etc.), along with acquisition of 3D point cloud data of the mines (R.9). For these initial exploration missions, the UX-1 is connected to control rooms set-up at each mine site via a tether connection, for real-time monitoring and visualization. The tests are semi-autonomous, where an operator on the mission workstation (see P.III) teleoperates the UX-1 vehicle in the surge and sway motions, and occasionally the heading; whilst the depth of the robot is fully controlled with the NSFL motion control system to solve the setpoint regulation control objective (O.3.1) and the roll is fixed at φ = 0 rad. This decision is made in order to allow local geologists and mine personnel to guide the exploration tasks and acquire as much mineralogical and structural data as possible from the scientific instrumentation. Table 4.5 shows the overall results obtained during the exploration missions in P.III.

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Implementación de la tecnología Generic Motion Control Y Powerlink sobre un robot industrial de configuración cartesiana para la empresa CAE Solutions Ec

Implementación de la tecnología Generic Motion Control Y Powerlink sobre un robot industrial de configuración cartesiana para la empresa CAE Solutions Ec

Existen tecnologías de sistemas neumáticos, hidráulicos, eléctricos y mixtos, cada uno utilizado en diferentes áreas con propósitos generales; en el robot cartesiano se presenta una tecnología mixta eléctrica y neumática con la cual nos permite desarrollar de manera óptima el paletizado de objetos; éstas tecnologías son controladas con PLC´s o con PC industriales en donde se ocupa protocolos de comunicación y programación para el control de los sistemas mencionados; en el robot cartesiano se utiliza la comunicación mediante ETHERNET POWERLINK que es un protocolo a nivel industrial y para el control se utiliza GENERIC MOTION CONTROL que es una librería de Automation Studio, herramientas muy poderosas y precisas para la manipulación de procesos industriales.

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Kinematic task space scheme for 3 dof pneumatic parallel robot in motion control application

Kinematic task space scheme for 3 dof pneumatic parallel robot in motion control application

The control scheme was tested on the 3DOF pneumatic parallel robot. The inner and the external loops are both implemented in a Pentium-D 3.00-GHz connected to the robot through a Humusoft MF624 board. The board reads the joint’s positions from linear potentiometric sensors, executes the control algorithm and gives the control signal to the electro-pneumatic valves with a sampling period of 1 ms. The task space variables are acquired by the same card, reading an encoder for the height; and pitch and roll angles via IMU [15]. In this loop the inverse kinematic problem is solved and the obtained vector of joint’s coor- dinates q d is given as desired joint positions to the internal

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THE YASKAWA QUALITY EXPERIENCE

THE YASKAWA QUALITY EXPERIENCE

As a final step before release, Yaskawa drives and motion control products are installed in customer beta sites to perform application testing under actual conditions. Information learned during this process is incorporated into final product design before manufacturing begins. The result of this obsessive dedication to quality design – before we start to manufacture – is the certainty that we have it right. This process will improve performance, increase uptime, and lower cost of ownership.

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Diseño e implementación del sistema de control de iluminación de una vivienda, controlado por el dispositivo Leap Motion, basado en realidad virtual

Diseño e implementación del sistema de control de iluminación de una vivienda, controlado por el dispositivo Leap Motion, basado en realidad virtual

Se desarrolló un entorno virtual del interior de la vivienda, visualizando la ubicación de cada área, desde donde el usuario pudo activar, desactivar y controlar la iluminación con el uso de gestos específicos reconocidos por el Leap Motion. Durante el desarrollo de este entorno virtual y gracias a las diferentes pruebas de funcionamiento que se realizaron, se determinó que el control debe ser lo más ergonómico y de fácil aprendizaje; sin embargo, al ser el dispositivo LEAP MOTION bastante sensible, los gestos “SCREEN_TAP” y “KEY_TAP”, deben ser ejecutados lo más exactos posible. También, cuando se esté utilizando el dispositivo para recorrer a lo largo del entorno, es importante que los dedos estén estirados y separados entre sí.

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Exploración en tecnologías emergentes:Sensor  gestual “Leap Motion”

Exploración en tecnologías emergentes:Sensor gestual “Leap Motion”

Exploración en tecnologías Emergentes: Sensor Gestual “Leap Motion” Página 8 Dependiendo de la intención tendrá que tomar diferentes factores ergonómicos en cuenta. Si su aplicación está destinada para un uso prolongado, considerar el diseño de todas sus interacciones para que alguien pueda realizar con su codo apoyado en una mesa. Si su diseño necesita manos y los brazos de la gente y en movimiento, diseño con períodos de descanso, y las explosiones cortas de interacción. ¿Dónde la gente usa su aplicación? En su ordenador portátil mientras está sentado en la cama, en una silla en su escritorio, de pie en la cocina. Cada entorno tiene sus propios desafíos, limitaciones y oportunidades.

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Desarrollo y control de un sistema de movilidad para subir escaleras

Desarrollo y control de un sistema de movilidad para subir escaleras

T HIS chapter addresses the trajectory tracking control problem of robotic wheelchairs in the presence of modeling uncertainties. A global ultra-model, or simplified model derived from flatness considerations, is first proposed. This model greatly reduces the complexity of the design of the state estimation and the output feedback control tasks since it groups, as an unknown time-varying disturbance, both the combined effects of all uncertain state-dependent (i.e., en- dogenous) nonlinearities and those of external (i.e., exogenous) perturbation inputs which are present in the input-to-flat output model of the system. An extended linear high-gain observer, or GPI observer, is then developed for the simultaneous, although approximate, state and disturbance estimation. The proposed feedback controller combines the global ultra-model and the GPI observers in order to obtain an active disturbance rejection, or disturbance accommodation, control scheme. The simulation results presented in the chapter show that the proposed method has a good tracking performance and robustness in the presence of system uncertainties, external disturbances and noisy corruptions. These results suggest that this method can be used to control our SCMS during the approaching the first step stage.

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TítuloSkeletal level control based forward dynamic analysis of acquired healthy and assisted gait motion

TítuloSkeletal level control based forward dynamic analysis of acquired healthy and assisted gait motion

In the second option, the orthoses were considered as independent bodies (see Fig. 19). The lower link of each orthosis was connected to the subject's ankle by a revolute joint in the direction of the ankle axis, obtained upon processing of the acquired motion, while the upper link was connected to the lower link by another revolute joint at knee level, so that each orthosis added two degrees of freedom. Inertial properties were assigned to the corresponding bodies. Moreover, torsional spring-damper elements were included in the revolute joints at knee and ankle levels to represent the locking and anti-foot-drop mechanisms, respectively. The limb/orthosis connecting elements were modeled by linear spring-dampers linking points of the limb and the orthosis, both at hip and knee levels. Additional natural coordinates were required this time to include the new four bodies in the 3D human model of sub-section 7.1. As illustrated in Fig. 19, for each orthosis one new point was defined at knee level (p1) and another one at hip level (p2), while the point at ankle level was simply shared with that already defined in the joint of the human model. Moreover, three new unit vectors were required for each part: v1 (shared with the foot) in the direction of the orthotic ankle axis, v2 and v3 for the lower link; v4 (shared with the lower link) in the direction of the orthotic knee axis for the upper link. Unit vector v1 is calculated from the acquired motion, as it is not known a priori. Also, it must be noted that the orthotic ankle and knee axes can be different, and in fact they were in the case addressed, so that v1 and v4 might not be the same unit vector. Finally, the relative angles between foot and lower link, and between lower and upper links, respectively, were also added to the list (they are not drawn in Fig. 19 due to the lack of space). Therefore, a total increment of four points, twelve unit vectors and four angles was registered for the two devices, so that the resulting 3D human model including orthoses as independent bodies and crutches possessed 61 degrees of freedom and was defined by a total of 298 mixed (natural and angular) dependent coordinates. The configuration vector z of 61 independent coordinates was formed by the three Cartesian coordinates of the lumbar joint plus the 18 sets of three angles defining the orientation of the bodies (Fig. 1), plus the two sets of two relative angles locating each orthotic open chain starting at the corresponding subject's ankle.

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Methods for the analysis of multi-scale cell dynamics from fluorescence microscopy images

Methods for the analysis of multi-scale cell dynamics from fluorescence microscopy images

From a theoretical perspective, this PhD Thesis addresses how mechanical processes can be quan- tified from images and their digital reconstruction. We grounded the methodology with continuum mechanics theory relying on a Lagrangian representation of the cell dynamics. This representation of physical dynamics is based on a particle-based description of the system, so the quantification of the motion is expressed in terms of trajectories (movement of fluid particles or material points of a solid). This representation is alternative to the Eulerian perspective that is based on spatial represen- tation of the system referred to an external observer. Interestingly, the way processes are imaged with microscopes external to the embryo has led to a generalized Eulerian approach of analysis of biolog- ical phenomena. The study of deformation patterns in embryogenic tissues from in-vivo images has been restricted to an analysis of deformation from the displacements and cell morphology dynamics between time steps [Blanchard et al., 2009, Bosveld et al., 2012]. This approach provides a detailed description of mechanical patterns and interactions with other genetic and biochemical factors, but do not produce a description of the temporal scales of the patterns required to understand how me- chanical patterns affecting cells evolve through time. The reconfiguration of the tissues along the shaping process requires a Lagrangian framework to better characterize the different length-scales of the processes. The cells move at the same time embryos are shaped, therefore, the mechanical patterns seen from an Eulerian perspective can only be mapped instantaneously (in the same way the embryo is observed from the microscope). However, within a Lagrangian (material) analysis, mechanical patterning can be quantified in finite time intervals along the trajectories

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Laser induced dynamics of interacting small particles

Laser induced dynamics of interacting small particles

In summary, we have studied the motion of a pair of small particles in a laser field under the force of the induced polarization. Our main finding is that for particles starting from rest, the size of the phase space is larger for initial positions leading to touching than for diverging trajectories, thus favoring clustering. In the limit of zero viscosity, at which the boundary separating bounded from unbounded tra- jectories is approximately 63°, the probability that a particle lies within the clustering region in a spherical volume sur- rounding the first particle may be estimated as 0.71. This value, exact for vacuum, is still appropriate for low viscosity fluids such as air. However, when the viscosity grows, the boundary moves to higher angular values increasing the probability for clustering trajectories, saturating to essen- tially 100% binding when the viscosity reaches a value of about 10 −2 N s / m 2 . If light is circularly polarized, then all

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Solving motion planning problems

Solving motion planning problems

From the problem complexity side, the nondeterministic constraint logic model [4] provides a set of tools to construct PSPACE-hardness proofs for motion planning problems. Using this model we prove that several variants of movable blocks with pull moves are PSPACE-complete strengthen previous results. We also use this model to investigate the hardness of Pukoban and some of its vari- ants with push and pull moves. So far, we are able to prove that all variants in which the man can move at least three stones at a time are PSPACE-complete, again strengthen previous results.

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Automatic aerial target detection and tracking system in
airborne FLIR images based on efficient target trajectory
filtering

Automatic aerial target detection and tracking system in airborne FLIR images based on efficient target trajectory filtering

Most of the works address each task, detection and tracking, independently along with a method to com- pensate or limit the ego-motion effect. In [1]-[2] motion-based segmentation schemes with a previous ego-motion compensation stage are presented, but their approach tends to produce an over-detection. Besides, the high complexity of the ego-motion compensation approaches used in these works limits their applicability in real-time systems. To solve this problem, [3] employs a multi-resolution pyramid to reduce the computational burden. In [4]-[5] similar ego-motion compensation schemes are used when target tracking fails because of large camera displacements, but there is not any feedback to the detection stage. Others works, as in [6], expand the target search area in the tracking process to alleviate the camera ego-motion without using any explicit compensation technique. But, this approach lacks flexibility and its computational burden increases with the size of the search area.

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High definition video quality assessment metric built upon full reference ratios

High definition video quality assessment metric built upon full reference ratios

40 Similar to the VSSIM, Lu et al. [89] proposed a full reference video quality assessment model based on structural distortion measurements. The first stage selects localized areas and computes statistical features, such as mean and variance, to obtain the local quality and the frame quality measure (as in VSSIM). The authors then adjust the frame quality value by measuring the blockiness and blurriness as well as the motion factor. Blocking and blurring, which are measured from the power spectrum of the signal, as well as the relative motion, which is measured using a block-based motion compensation algorithm, are incorporated adaptively based on the quality index of the frame. The final frame quality index is obtained as a weighted sum of the results for Y, Cr, and Cb. Averaging over all frames gives the overall quality value for the test sequence. The metric was tested with the VQEG Phase 1 data set and showed consistency with subjective measurements when evaluated using the Spearman and the Pearson coefficients. Applications such as low bit rate MPEG coding suit the metric. Shnayderman et al. [90] developed a distortion measure called M-SVD (Mean Singular Value Decomposition) for image quality assessment based on the concept of singular value decomposition. Singular Value Decomposition is a way of factoring matrices into a series of linear approximations that expose the underlying structure of the matrix. The M-SVD measures distortion as a function of the distance between the original and distorted image block singular values, given by

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Enseñar con Motion Graphics / Teaching with Motion Graphics

Enseñar con Motion Graphics / Teaching with Motion Graphics

En definitiva, la educación está en constante evolución gracias a las nuevas tecnologías, debemos aprender a comunicar a través de estas nuevas herramientas y hacer que este conocimiento se accesible para   cualquiera.   Los  Motion   Graphics  educativos   pueden   ejercer   una   gran   influencia   ya   que   nos impregnamos   de   estas   imágenes   y   empezamos   a   adquirir   pautas   estilísticas   que   influyen   en   el aprendizaje   estético   en   cuanto   al   color,   la   composición,   la   representación,   etcétera.   Fomentar   la imaginación a través de la animación puede aportar una experiencia muy enriquecedora para acercar a nuestros alumnos a «conquistar el futuro con la ayuda de su imaginación creadora» (Vigotsky, 1986:108).

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Analyzing of the vocal fold dynamics using laryngeal videos

Analyzing of the vocal fold dynamics using laryngeal videos

• The authors in (Ko and Ciloglu, 2014) present a novel illumination model based on the mean intensity distribution along the longitudinal cross section of the center of the glottis. Then, the new histogram distribution is modeled by a Gaussian Mixture Model (GMM) and the estimated GMM is used to isolate the glottis from the background. However, this method neglects the global drift and therefore does not provide any type of motion compensation. • The authors in (Gloger et al., 2015) propose a fully automatic method to segment the glottis using local color and shape information. They divide the approach in three modules: training, recognition and segmentation. In the training, 60 different glottis shapes are manually segmented, and a set of descriptors are computed. The recognition module is designed to recognize, delineate and determine the optimal starting glottis regions. The last mod- ule segments the glottis based on properties of the previous frame. Hence, the glottis is continuously tracked within vibration cycles of the video by a frame-by-frame-wise segmentation technique.

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Bioquímica en stop motion

Bioquímica en stop motion

Para desarrollar la actividad, los estudiantes deben en primer lugar escribir un guión, este escrito es la base conceptual, ya que se deben hacer evidentes los pasos consecutivos, los protagonistas de cada acción y obviamente debe condensar la información en una línea lógica de pensamiento. Después, una vez aprobado el guión, se da inicio al proceso de filmación, en el que se da libertad de utilizar materiales e ideas de libre elección, de tal manera que finalmente expliquen el fenómeno estudiado. Cómo la técnica de stop motion requiere de un uso muy limitado de herramientas, una cámara de fotografía digital y un software de edición de video, hay muchas variables que los estudiantes pueden explorar y que depende de su elección implementar.

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Development of a control system of an exoskeleton for assistance of elbow motion

Development of a control system of an exoskeleton for assistance of elbow motion

El propósito del dispositivo que se menciona en este trabajo es amplificar la fuerza del sistema muscular humano, sin perder el control natural de los movimientos, es por ello que los típicos controles de posición para las máquinas, no son aplicables, pues cuando el humano proporciona el comando de referencia de posición se pierde la naturalidad de los movimientos, además se quiere dar una ganancia constante, a la fuerza ejercida por la persona, la cual es la variable a controlar.

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Newton’s Laws of Motion

Newton’s Laws of Motion

If any force generates a motion, a double force will generate double the motion, a triple force triple the motion, whether that force is impressed altogether and at once or gradually and successively. And this motion (being always directed the same way with the generating force), if the body moved before, is added or subtracted from the former motion, according as they directly conspire with or are directly contrary to each other; or obliquely joined, when they are oblique, so as to produce a new motion compounded from the determination of both.

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