Segmented capacitance tomography electrodes: a design and experimental verifications

A segmented capacitance tomography system for real-time imaging of multiphase flows is developed and pre-sented in this work. The earlier research shows that the electrical tomography (ECT) system is applicable in flow visualization (image reconstruction). The acquired concentration profile ob-tained from capacitance measurements able to imaged liquid and gas mixture in pipelines meanwhile the system development is designed to attach on a vessel. The electrode plates which act as the sensor previously has been assembled and fixed on the pipeline, thus it causes obscurity for the production to have any new process installation in the future. Therefore, a segmented electrode sensor offers a new design and idea on ECT system which is portable to be assembled in different diameter sizes of pipeline, and it is flexible to apply in any number due to different size of pipeline without the need of redesigning the sensing module. The new ap-proach of this sensing module contains the integration intelligent electrode sensing circuit on every each of electrode sensors. A microcontroller unit and data acquisition (DAQ) system has been integrated on the electrode sensing circuit and USB technology was applied into the data acquisition system making the sensor able to work independently. Other than that the driven guard that usually placed between adjacent measuring electrodes and earth screen has been embedded on the segmented electrode sensor plates. This eliminates the cable noise and the electrode, so the signal conditioning board can be expanded according to pipe diameter

A novel design process of low cost 3D printed ambidextrous finger designed for an ambidextrous robotic hand

This paper presents the novel mechanical design of an ambidextrous finger specifically designed for an ambidextrous anthropomorphic robotic hand actuated by pneumatic artificial muscles. The ambidextrous nature of design allows fingers to perform both left and right hand movements. The aim of our design is to reduce the number of actuators, increase the range of movements with best possible range ideally greater than a common human finger. Four prototypes are discussed in this paper; first prototype is focused on the choice of material and to consider the possible ways to reduce friction. Second prototype is designed to investigate the tendons routing configurations. Aim of third and fourth prototype is to improve the overall performance and to maximize the grasping force. Finally, a unified design (Final design) is presented in great detail. Comparison of all prototypes is done from different angles to evaluate the best design. The kinematic features of intermediate mode have been analysed to optimize both the flexibility and the robustness of the system, as well as to minimize the number of pneumatic muscles. The final design of an ambidextrous finger has developed, tested and 3D printed

Prehensile Pushing: In-hand Manipulation with Push-Primitives

This paper explores the manipulation of a grasped object by pushing it against its environment. Relying on precise arm motions and detailed models of frictional contact, prehensile pushing enables dexterous manipulation with simple manipulators, such as those currently available in industrial settings, and those likely affordable by service and field robots. This paper is concerned with the mechanics of the forceful interaction between a gripper, a grasped object, and its environment. In particular, we describe the quasi-dynamic motion of an object held by a set of point, line, or planar rigid frictional contacts and forced by an external pusher (the environment). Our model predicts the force required by the external pusher to “break” the equilibrium of the grasp and estimates the instantaneous motion of the object in the grasp. It also captures interesting behaviors such as the constraining effect of line or planar contacts and the guiding effect of the pusher’s motion on the objects’s motion. We evaluate the algorithm with three primitive prehensile pushing actions—straight sliding, pivoting, and rolling—with the potential to combine into a broader in-hand manipulation capability.National Science Foundation (U.S.). National Robotics Initiative (Award NSF-IIS-1427050)Karl Chang Innovation Fund Awar

Manos Robóticas Antropomórficas: una revisión

This paper presents a review on main topic regarding to anthropomorphic robotic hands developed in the last years, taking into account the more important mechatronics designs submit on the literature, and making a comparison between them. The next chapters deepen on level of anthropomorphism and dexterity in advanced actuated hands and upper limbs prostheses, as well as a brief overview on issues such as grasping, transmission mechanisms, sensory and actuator system, and also a short introduction on under-actuated robotic hands is reported.Este artículo presenta una revisión de los principales desarrollos que se han hecho en los últimos años en manos robóticas antropomórficas. Las primeras secciones tratan temas como el grado de antropomorfismo y de destreza en las manos robóticas más avanzadas, incluyendo una comparación entre ellas. También se abordan temas como la capacidad de agarre de los efectores finales, los mecanismos de trasmisión, el sistema actuador y sensórico, así como una breve introducción al tema de manos robóticas sub-actuadas. Dirección de correspondencia: Carrera 11 # 101-80, Bogotá (Colombia)

Pengembangan Desain, Simulasi Dan Pengujian Robot Tangan Menggunakan Flex Sensor Terintegrasi Dengan 3d Animation Simmechanics

Teknologi robotika merupakan salah satu teknologi yang penting dalam menentukan kemajuan peradaban di dunia. Teknologi robotika dapat meningkatkan produktivitas suatu pekerjaan. Dengan adanya robotika, pekerjaan yang sebelumnya sulit dan berbahaya untuk dikerjakan sekarang sudah dapat dikerjakan lebih mudah dan aman Dengan input dari sinyal flex sensor dapat menggerakkan tangan robot dan dengan 3D Animation SimMechanics operator dapat memantau apakah input masukan dari flex sensor tepat menggerakkan tangan robot tersebut. Selain kedua hal tersebut pada artikel ini juga akan membahas mengenai pengujian sudut motor servo saat digerakkan dibandingkan dengan sudut tiap join tangan robot yang menghadirkan tabel sudut pergerakan antara servo motor dan tiap join tangan robotnya. Dari pengujian tersebut dapat dilihat ksimpulan hubungan antara gerakan servo motor dengan tali elastis yang digunakan untuk menghasilkan gerakan Balik setelah tangan robot ditarik oleh aktuator. Untuk kinematik tangan robot, artikel ini akan membahas pemosisian inisial tangan robot dan forward kinematics pada tangan robot dengan menggunakan metode Denavit-Hartenberg. Invers kinematics juga akan menjadi bahasan dalam tugas akhir ini. Software yang digunakan pada penelitian ini adalah MATLAB SimMechanics sebagai media kontrol dari virtual reality dan juga digunakan SolidWorks sebagai media desain awal tangan robot Telah berhasil diintegrasikan kontrol dari input sinyal flex sensor dan pergerakan tangan robot serta 3D Animation SimMechanics. Pada perhitungan forward kinematics menghasilkan koordinat posisi tiap ujung jari tangan robot dengan input sudut theta yang disesuaikan dengan sudut gerakan pada tangan manusia sesungguhnya. Lalu untuk inverse kinematics menghasilkan sudut dari tiap jari tangan setelah diberikan koordinat posisi dari ujung jari tangan robotny

Planificación de movimientos para conjuntos mano-brazo con numerosos grados de libertad

Con el objetivo de avanzar hacia la emulaci ´on de las capacidades y destreza de la mano humana se est ´an desarrollando manos rob´oticas con prestaciones muy superiores a las tradicionales pinzas usadas en la rob´otica industrial. El uso de estas manos rob´oticas conlleva asociados nuevos retos, y entre ellos est ´a el de la planificaci ´on eficiente de sus movimientos, ya que aunque algunos m´etodos de planificaci ´on tradiciones podr´ıan ser v´alidos, su aplicaci ´on pr´actica es limitada debido sobre todo al elevado n´umero de grados de libertad que tiene un sistema rob´otico que incluya una mano antropomorfa montada sobre un brazo manipulador. Este art´ıculo presenta un enfoque que permite soluciones suficientemente eficientes para ser utilizadas en la pr´actica. El enfoque propuesto est ´a basado en la reducci ´on de la dimensi ´on del espacio de b´usqueda y en la utilizaci ´on de t´ecnicas de muestreo para generar movimientos del conjunto mano-brazo en entornos con obst ´aculos que pueden imponer fuertes restricciones en la b´usqueda de movimientos sin colisi ´on, como sucede normalmente cuando la mano se acerca a un objeto para su sujeci ´on y manipulaci ´on. Los desarrollos te´oricos han sido implementados tanto en simulaci ´on como en un sistema f´ısico real, por lo que se incluyen resultados experimentales reales.Postprint (published version

Grasp plannind under task-specific contact constraints

Several aspects have to be addressed before realizing the dream of a robotic hand-arm system with human-like capabilities, ranging from the consolidation of a proper mechatronic design, to the development of precise, lightweight sensors and actuators, to the efficient planning and control of the articular forces and motions required for interaction with the environment. This thesis provides solution algorithms for a main problem within the latter aspect, known as the {\em grasp planning} problem: Given a robotic system formed by a multifinger hand attached to an arm, and an object to be grasped, both with a known geometry and location in 3-space, determine how the hand-arm system should be moved without colliding with itself or with the environment, in order to firmly grasp the object in a suitable way. Central to our algorithms is the explicit consideration of a given set of hand-object contact constraints to be satisfied in the final grasp configuration, imposed by the particular manipulation task to be performed with the object. This is a distinguishing feature from other grasp planning algorithms given in the literature, where a means of ensuring precise hand-object contact locations in the resulting grasp is usually not provided. These conventional algorithms are fast, and nicely suited for planning grasps for pick-an-place operations with the object, but not for planning grasps required for a specific manipulation of the object, like those necessary for holding a pen, a pair of scissors, or a jeweler's screwdriver, for instance, when writing, cutting a paper, or turning a screw, respectively. To be able to generate such highly-selective grasps, we assume that a number of surface regions on the hand are to be placed in contact with a number of corresponding regions on the object, and enforce the fulfilment of such constraints on the obtained solutions from the very beginning, in addition to the usual constraints of grasp restrainability, manipulability and collision avoidance. The proposed algorithms can be applied to robotic hands of arbitrary structure, possibly considering compliance in the joints and the contacts if desired, and they can accommodate general patch-patch contact constraints, instead of more restrictive contact types occasionally considered in the literature. It is worth noting, also, that while common force-closure or manipulability indices are used to asses the quality of grasps, no particular assumption is made on the mathematical properties of the quality index to be used, so that any quality criterion can be accommodated in principle. The algorithms have been tested and validated on numerous situations involving real mechanical hands and typical objects, and find applications in classical or emerging contexts like service robotics, telemedicine, space exploration, prosthetics, manipulation in hazardous environments, or human-robot interaction in general

Progettazione e Controllo di Mani Robotiche

The application of dexterous robotic hands out of research laboratories has been limited by the intrinsic complexity that these devices present. This is directly reflected as an economically unreasonable cost and a low overall reliability. Within the research reported in this thesis it is shown how the problem of complexity in the design of robotic hands can be tackled, taking advantage of modern technologies (i.e. rapid prototyping), leading to innovative concepts for the design of the mechanical structure, the actuation and sensory systems. The solutions adopted drastically reduce the prototyping and production costs and increase the reliability, reducing the number of parts required and averaging their single reliability factors. In order to get guidelines for the design process, the problem of robotic grasp and manipulation by a dual arm/hand system has been reviewed. In this way, the requirements that should be fulfilled at hardware level to guarantee successful execution of the task has been highlighted. The contribution of this research from the manipulation planning side focuses on the redundancy resolution that arise in the execution of the task in a dexterous arm/hand system. In literature the problem of coordination of arm and hand during manipulation of an object has been widely analyzed in theory but often experimentally demonstrated in simplified robotic setup. Our aim is to cover the lack in the study of this topic and experimentally evaluate it in a complex system as a anthropomorphic arm hand system