载人潜水器及其运动控制

介绍了载人潜水器的构成及推进器的布置,在此基础上导出了载人潜水器的推力分配方程。阐述了载人潜水器的运动控制。最后,将运动控制系统在载人潜水器半物理仿真平台上进行了验证,运动控制效果良好。

履带式移动机器人行动规划技术的研究

本文以８６３－５１２型号项目为背景，从运动特性、运动描述、运动控制以及运动规划等几个方面研究履带式移动机器人的行动规划技术；首先从理论上分析了履带式移动机器人的内在运动传递机理，指出了其区别于轮式移动载体的独特的运动特性，尤其是在其转向特性方面，得出了履带式移动机器人运动角速度几乎不可控原理、原地转弯转不准问题、以及履带式车辆行动规划时所要遵循的规则等重要结论，针对履带式移动机器人的纵向运动控制问题，讨论了其速度控制模型，提出了一种速度测量与控制的简单、准确、可靠的方法。在磺向运动方面，提出了一种基于ＦＭ－ＬＩＫＥ和ＡＭ－ＬＩＫＥ相结合的复合控制技术，解决了难度较大的方向控制问题。最后提供了实验结果，证明了上述方法与结论的正确性。上述方法与结论，作为８６３－５１２某型号任务的一部分，业已通过验收。

全方位六足步行机器人运动规划的相对运动算法

本文提出了步行机器人运动控制算法。该方法以相对运动学原理为基础,把机体的运动规划问题转化为腿的足端轨迹规划问题,从而使步行机器人运动控制问题得到大大简化.并应用该方法对全方位三角步态算法及稳定性进行分析求解.

海绵卷绕真空磁控溅射镀膜过程中的传动控制

根据磁控溅射中海绵的传动特性,建立了传动控制的数学模型,采用带有矢量的变频调速器实现了海绵卷绕真空镀膜过程中的张力控制,满足了磁控溅射中海绵卷绕的传动要求。

A Binocular, Foveated Active Vision System

This report documents the design and implementation of a binocular, foveated active vision system as part of the Cog project at the MIT Artificial Intelligence Laboratory. The active vision system features a three degree of freedom mechanical platform that supports four color cameras, a motion control system, and a parallel network of digital signal processors for image processing. To demonstrate the capabilities of the system, we present results from four sample visual-motor tasks.

Constitutive model for localized Lüders-like stress-induced martensitic transformation and super-elastic behaviors of laser-welded NiTi wires

The application of the shape memory alloy NiTi in micro-electro-mechanical-systems (MEMSs) is extensive nowadays. In MEMS, complex while precise motion control is always vital. This makes the degradation of the functional properties of NiTi during cycling loading such as the appearance of residual strain become a serious problem to study, in particular for laser micro-welded NiTi in real applications. Although many experimental efforts have been put to study the mechanical properties of laser welded NiTi, surprisingly, up to the best of our understanding, there has not been attempts to quantitatively model the laser-welded NiTi under mechanical cycling in spite of the accurate prediction required in applications and the large number of constitutive models to quantify the thermo-mechanical behavior of shape memory alloys. As the first attempt to fill the gap, we employ a recent constitutive model, which describes the localized SIMT in NiTi under cyclic deformation; with suitable modifications to model the mechanical behavior of the laser welded NiTi under cyclic tension. The simulation of the model on a range of tensile cyclic deformation is consistent with the results of a series of experiments. From this, we conclude that the plastic deformation localized in the welded regions (WZ and HAZs) of the NiTi weldment can explain most of the extra amount of residual strain appearing in welded NiTi compared to the bare one. Meanwhile, contrary to common belief, we find that the ability of the weldment to memorize its transformation history, sometimes known as ‘return point memory’, still remains unchanged basically though the effective working limit of this ability reduces to within 6% deformation.

1-D constitutive model for evolution of stress-induced R-phase and localized Lüders-like stress-induced martensitic transformation of super-elastic NiTi wires

NiTi alloys have been widely used in the applications for micro-electro-mechanical-systems (MEMS), which often involve some precise and complex motion control. However, when using the NiTi alloys in MEMS application, the main problem to be considered is the degradation of functional property during cycling loading. This also stresses the importance of accurate prediction of the functional behavior of NiTi alloys. In the last two decades, a large number of constitutive models have been proposed to achieve the task. A portion of them focused on the deformation behavior of NiTi alloys under cyclic loading, which is a practical and non-negligible situation. Despite of the scale of modeling studies of the field in NiTi alloys, two experimental observations under uniaxial tension loading have not received proper attentions. First, a deviation from linearity well before the stress-induced martensitic transformation (SIMT) has not been modeled. Recent experiments confirmed that it is caused by the formation of stress-induced R phase. Second, the influence of the well-known localized Lüders-like SIMT on the macroscopic behavior of NiTi alloys, in particular the residual strain during cyclic loading, has not been addressed. In response, we develop a 1-D phenomenological constitutive model for NiTi alloys with two novel features: the formation of stress-induced R phase and the explicit modeling of the localized Lüders-like SIMT. The derived constitutive relations are simple and at the same time sufficient to describe the behavior of NiTi alloys. The accumulation of residual strain caused by R phase under different loading schemes is accurately described by the proposed model. Also, the residual strain caused by irreversible SIMT at different maximum loading strain under cyclic tension loading in individual samples can be explained by and fitted into a single equation in the proposed model. These results show that the proposed model successfully captures the behavior of R phase and the essence of localized SIMT.

Active design of tooth profiles using parabolic curve as the line of action

This paper proposes a method for the design of gear tooth profiles using parabolic curve as its line of action. A mathematical model, including the equation of the line of action, the equation of the tooth profile, and the equation of the conjugate tooth profile, is developed based on the meshing theory. The equation of undercutting condition is derived from the model. The influences of the two design parameters, that present the size (or shape) of the parabolic curve relative to the gear size, on the shape of tooth profiles and on the contact ratio are also studied through the design of an example drive. The strength, including the contact and the bending stresses, of the gear drive designed by using the proposed method is analyzed by an FEA simulation. A comparison of the above characteristics of the gear drive designed with the involute gear drive is also carried out in this work. The results confirm that the proposed design method is more flexible to control the shape of the tooth profile by changing the parameters of the parabola.

Autonomous Surface Vehicle Docking Manoeuvre with Visual Information

This work presents a hybrid coordinated manoeuvre for docking an autonomous surface vehicle with an autonomous underwater vehicle. The control manoeuvre uses visual information to estimate the AUV relative position and attitude in relation to the ASV and steers the ASV in order to dock with the AUV. The AUV is assumed to be at surface with only a small fraction of its volume visible. The system implemented in the autonomous surface vehicle ROAZ, developed by LSA-ISEP to perform missions in river environment, test autonomous AUV docking capabilities and multiple AUV/ASV coordinated missions is presented. Information from a low cost embedded robotics vision system (LSAVision), along with inertial navigation sensors is fused in an extended Kalman filter and used to determine AUV relative position and orientation to the surface vehicle The real time vision processing system is described and results are presented in operational scenario.

Una metodología activa en quinto de EGB : influencias en el rendimiento discente en el Ciclo Superior.

Demostrar que la participación de la comunidad escolar en la organización, planificación, proceso flexible y control de la estrategia metodológica activa de enseñanza-aprendizaje para quinto nivel de EGB, tiene una influencia positiva en la formación posterior del alumno, diferenciando según contenidos y cursos, con respecto a los normalmente empleados en los centros de coste similar. Obtiene al azar un grupo B de quinto de EGB de Santurce, actuando el grupo A como grupo control. La investigación se realiza en el mismo nivel a lo largo de 3 años, y en el seguimiento de los alumnos de sexto a octavo (según evolución del curso). Éstos serán comparados a su vez con otros alumnos de otros centros tomados al azar. Realiza un análisis teórico sobre motivación, problemática educativa al respecto y reforma educativa, estudia estos aspectos y las metodologías afines. Tras la formación operativa de conceptos hace un estudio científico-experimental, utilizando el método hipotético deductivo. Tras formular la hipótesis realiza un estudio transversal y longitudinal con alumnos de Ciclo Superior, de los que se extrae la información que tras un análisis factorial lleva a los resultados-conclusiones. Al final propone una hipótesis de trabajo posterior (prospectiva). Encuestas (pretest-posttest). Actas de la evaluación final de junio. Sondeos sobre tónica de enseñanza en los diferentes centros de la investigación. Índices de tendencia central, correlaciones, porcentajes y pruebas de significación: TAU, CHI cuadrado, 'F' de Fisher, etc. La participación de la comunidad escolar en la organización, planificación, proceso flexible y control de la estrategia metodológica activa de la enseñanza-aprendizaje influye significativamente, según el pretest, en un primer momento sobre la formación del alumno, pero no se puede afirmar que influya en la formación posterior (posttest) del mismo. Resalta la importancia de la enseñanza no directiva.

Invasive neural prosthesis for neural signal detection and nerve stimulation

This paper specifically examines the implantation of a microelectrode array into the median nerve of the left arm of a healthy male volunteer. The objective was to establish a bi-directional link between the human nervous system and a computer, via a unique interface module. This is the first time that such a device has been used with a healthy human. The aim of the study was to assess the efficacy, compatibility, and long term operability of the neural implant in allowing the subject to perceive feedback stimulation and for neural activity to be detected and processed such that the subject could interact with remote technologies. A case study demonstrating real-time control of an instrumented prosthetic hand by means of the bi-directional link is given. The implantation did not result in infection, and scanning electron microscope images of the implant post extraction have not indicated significant rejection of the implant by the body. No perceivable loss of hand sensation or motion control was experienced by the subject while the implant was in place, and further testing of the subject following the removal of the implant has not indicated any measurable long term defects. The implant was extracted after 96 days. Copyright © 2004 John Wiley & Sons, Ltd.

The application of implant technology for cybernetic systems

Objective: To assess the usefulness, compatibility, and long-term operability of a microelectrode array into the median nerve of the left arm of a healthy volunteer, including perception of feedback stimulation and operation of an instrumented prosthetic hand. Setting: The study was carried out from March 14 through June 18, 2002, in England and the United States. Results: The blindfolded subject received feedback information, obtained from force and slip sensors on the prosthetic hand, and subsequently used the implanted device to control the hand by applying an appropriate force to g rip an unseen object. Operability was also demonstrated remotely via the Internet, with the subject in New York, NY, and the prosthetic hand in Reading, England. Finally, the subject was able to control an electric wheelchair, via decoded signals from the implant device, to select the direction of travel by opening and closing his hand. The implantation did not result in infection or any perceivable loss of hand sensation or motion control. The implant was finally extracted because of mechanical fatigue of the percutaneous connection. Further testing after extraction has not indicated any measurable long-term defects in the subject. Conclusions: This implant may allow recipients to have abilities they would otherwise not possess. The response to stimulation improved considerably during the trial, suggesting that the subject learned to process the incoming information more effectively.

Exploiting ungrounded tactile haptic displays for mobile robotic teleoperation

Teleoperated mobile robotics offer potential use in a variety of different real-world applications including hazardous materials handling, urban search and rescue and explosive ordnance handling and disposal. Recent research discusses the use of Haptic technology in increasing task immersion and teleoperator performance. This work investigates the utility of low-cost, ungrounded tactile haptic interfaces in mobile robotic teleoperation. In order to achieve the desired implementation using only tactile sensation presents distinct challenges. Innovative haptic control methodologies providing the teleoperator with intuitive motion control and task-relevant haptic augmentation are presented within this paper.

Exploiting ungrounded tactile haptic displays for mobile robotic teleoperation

Teleoperated mobile robotics offer potential use in a variety of different real-world applications including hazardous materials handling, urban search and rescue and explosive ordnance handling and disposal. Recent research discusses the use of Haptic technology in increasing task immersion and teleoperator performance. This work investigates the utility of low-cost, ungrounded tactile haptic interfaces in mobile robotic teleoperation. In order to achieve the desired implementation using only tactile sensation presents distinct challenges. Innovative haptic control methodologies providing the teleoperator with intuitive motion control and task-relevant haptic augmentation are presented within this paper.