Compliant multi-fingered adaptive robotic gripper

Passively compliant underactuated mechanisms are one way to obtain the finger which could accommodate to any irregular shaped and sensitive grasping object. The purpose of the underactuation is to use the power of one actuator to drive the open and close motion of the gripper. The fully compliant mechanism has multiple degrees of freedom and can be considered as an underactuated mechanism. This paper presents design of the adaptive underactuated compliant multi-fingered gripper with distributed compliance. The optimal topology of the finger structure was obtained by an iterative optimization procedure. It was proven that for real robotic applications multi-fingered grippers with three or more fingers were more suitable for stable and safe grasping.Passiven nachgiebigen unteraktuierten Mechanismen bieten die Möglichkeit solche Robotergreifer zu entwerfen die anpassfähig an irgendeine unregelmäßig geformte und empfindliche Greifobjekt sind. Der Zweck der Unteraktuierung ist nur ein Aktor für die Greifer-öffnen/schließen-Funktionen zu benutzen. Völlig nachgiebige Mechanismus hat grosse Anzahl der Freiheitsgrade und man kann als unteraktuierte Mechanismus betrachtet werden. In diesem Beitrag wird ein adaptive unteraktuierte nachgiebige Multifinger-Greifer mit verteilten Nachgiebigkeit entworfen. Die optimale Topologie der Fingerstruktur wurde durch ein iteratives Optimisationverfahren bekommen. Es wurde bewährt dass für die realen Anwendungen der Multifinger-Greifer mit drei und mehr Fingern für stabile und sichere Greifen besser geeignet ist

Stiffness Control With Shape Memory Polymer in Underactuated Robotic Origamis

Underactuated systems offer compact design with easy actuation and control but at the cost of limited stable con- figurations and reduced dexterity compared to the directly driven and fully actuated systems. Here, we propose a compact origamibased design in which we can modulate the material stiffness of the joints and thereby control the stable configurations and the overall stiffness in an underactuated robot. The robotic origami, robogami, design uses multiple functional layers in nominally twodimensional robots to achieve the desired functionality. To control the stiffness of the structure, we adjust the elastic modulus of a shape memory polymer using an embedded customized stretchable heater. We study the actuation of a robogami finger with three joints and determine its stable configurations and contact forces at different stiffness settings. We monitor the configuration of the finger using feedback from customized curvature sensors embedded in each joint. A scaled down version of the design is used in a two-fingered gripper and different grasp modes are achieved by activating different sets of joints

Design and Development of Sensor Integrated Robotic Hand

Most of the automated systems using robots as agents do use few sensors according to the need. However, there are situations where the tasks carried out by the end-effector, or for that matter by the robot hand needs multiple sensors. The hand, to make the best use of these sensors, and behave autonomously, requires a set of appropriate types of sensors which could be integrated in proper manners. The present research work aims at developing a sensor integrated robot hand that can collect information related to the assigned tasks, assimilate there correctly and then do task action as appropriate. The process of development involves selection of sensors of right types and of right specification, locating then at proper places in the hand, checking their functionality individually and calibrating them for the envisaged process. Since the sensors need to be integrated so that they perform in the desired manner collectively, an integration platform is created using NI PXIe-1082. A set of algorithm is developed for achieving the integrated model. The entire process is first modelled and simulated off line for possible modification in order to ensure that all the sensors do contribute towards the autonomy of the hand for desired activity. This work also involves design of a two-fingered gripper. The design is made in such a way that it is capable of carrying out the desired tasks and can accommodate all the sensors within its fold. The developed sensor integrated hand has been put to work and its performance test has been carried out. This hand can be very useful for part assembly work in industries for any shape of part with a limit on the size of the part in mind. The broad aim is to design, model simulate and develop an advanced robotic hand. Sensors for pick up contacts pressure, force, torque, position, surface profile shape using suitable sensing elements in a robot hand are to be introduced. The hand is a complex structure with large number of degrees of freedom and has multiple sensing capabilities apart from the associated sensing assistance from other organs. The present work is envisaged to add multiple sensors to a two-fingered robotic hand having motion capabilities and constraints similar to the human hand. There has been a good amount of research and development in this field during the last two decades a lot remains to be explored and achieved. The objective of the proposed work is to design, simulate and develop a sensor integrated robotic hand. Its potential applications can be proposed for industrial environments and in healthcare field. The industrial applications include electronic assembly tasks, lighter inspection tasks, etc. Application in healthcare could be in the areas of rehabilitation and assistive techniques. The work also aims to establish the requirement of the robotic hand for the target application areas, to identify the suitable kinds and model of sensors that can be integrated on hand control system. Functioning of motors in the robotic hand and integration of appropriate sensors for the desired motion is explained for the control of the various elements of the hand. Additional sensors, capable of collecting external information and information about the object for manipulation is explored. Processes are designed using various software and hardware tools such as mathematical computation MATLAB, OpenCV library and LabVIEW 2013 DAQ system as applicable, validated theoretically and finally implemented to develop an intelligent robotic hand. The multiple smart sensors are installed on a standard six degree-of-freedom industrial robot KAWASAKI RS06L articulated manipulator, with the two-finger pneumatic SHUNK robotic hand or designed prototype and robot control programs are integrated in such a manner that allows easy application of grasping in an industrial pick-and-place operation where the characteristics of the object can vary or are unknown. The effectiveness of the actual recommended structure is usually proven simply by experiments using calibration involving sensors and manipulator. The dissertation concludes with a summary of the contribution and the scope of further work

10. Kolloquium Getriebetechnik: Technische Universität Ilmenau, 11. - 13. September 2013

In diesem Band sind die Beiträge des 10. Kolloquiums Getriebetechnik 2013 in Ilmenau zusammengestellt. Getriebe für Web- und Flechtmaschinen, für Schränke und Sessel, ein Schlagmechanismus für eine bevorstehende Marsmission, Robotersysteme für Mensch-Maschine-Schnittstellen, ein Mechanismus in einem Großteleskop oder Präzisionsmessgerät, ein einfacher Federbügel sowie nachgiebige Aktuatoren und Mechanismen – das sind nur einige von den hoch interessanten Systemen, die in diesem Band vorzufinden sind.This conference volume contains the contributions of the 10th "Kolloquium Getriebetechnik" 2013 in Ilmenau. Mechanisms for weaving and braiding machines, for boards and chairs, a hammering mechanism for an upcoming mission to Mars, robotic systems for human-machine interfaces, a mechanism in a large telescope or precision instrument, a simple spring clip and compliant actuators and mechanisms – these are just a few of the interesting systems that can be found in this volume