Design and Experimental Investigations of Shape and Attitude Carding System for the Wires of Micro Coreless Motor Winding

The shape and attitude (S&A) of the electrode wire are important characteristics of micro coreless motor winding. The purpose of this paper is to present the design of a robotic micro-manipulation system for micro wire carding with arbitrary S&A, which can be used as the pretreatment system for wire micro-gripper systems. The system is based on the principle of flexible carding, and uses nylon, bristle, nanometer-silk and wool as materials for the brushing micro-manipulator. The trajectory of the brushing micro-manipulator is designed, and the S&A of the electrode wires are straightened through the combined motion mode of horizontal and vertical brushing micro-manipulators. The experimental results show that the material of the brushing micro-manipulator has a great impact on the carding quality. Nanometer-silk material is more suitable for horizontal brushing micro-manipulators, and wool material is more suitable for vertical brushing micro-manipulators. The geometric dimension of the brushing micro-manipulator also affects the carding quality. When the diameter is in the range of 1 mm, the carding effect of the horizontal brushing micro-manipulator with a length of 4.9–8 mm is better. The system can realize the automatic carding of flexible electrode wires with arbitrary S&A, and it will not damage the structure of wires in the process.

Unsupervised Learning based Degradation Estimation and Abnormal Working Condition Detection for a Class of Anthropomorphic Robotic Hand

Grasping is one of the most common tasks related to robotics and manipulation which has received an extensive amount of contributions from the research community. From a design point of view, the robotic gripper systems are generally manufactured using a significant amount of small moving parts, in order to establish a balance between size, weight and performance. This balance leads to designs and components that are less robust than those of, for example, pneumatic grippers. To the best of our knowledge, most of the literature related to robotic grasping concentrates and focuses on grasping from a cognitive perspective. However, in order to ensure the execution of grasping tasks over extended periods of time, reducing down times and increasing gripper availability, even in demanding scenarios without access to maintenance, other phenomena such as component tear and degradation have to be monitored and analysed. This paper proposes an unsupervised learning model based approach for the estimation of the degradation states and the detection of abnormal working conditions of the actuator components for a class of robotic anthropomorphic hand. The approach allows an easy implementation and establishes the basis for the development of remaining useful life estimation algorithms for the components of other gripper systems. Our proposed architecture consists of an automatic degradation estimator and working condition detector, based on an unsupervised model combining K-means and Gaussian Mixture Models. The model estimates the hand's actuators degradation and determines its working condition from the online data collected during grasping tasks considering different objects. The proposed method was experimentally tested on a real Schunk SVH Hand used to assist humans during the assembly process in the automobile industry.

3D truss structures with coreless 3D filament winding technology

A coreless manufacturing process for generic 3D rigid frame topologies will be introduced in this paper. The aim is to extend the field of filament winding from mainly 2D-shells and some exceptional cases of 3D rigid frames. This manufacturing process employs a coreless translation cross-winding method in order to continuously deposit a roving around deflection points in space. On this basis, a design methodology is being created and deductively verified by designing a beam for a three-point bending load case. The composite beam is designed on a macro level simulation approach to match the stiffness of a reference aluminum profile, which is commonly employed as structural component for robotic gripper systems in automotive assemblies. The performance of the beams is subsequently compared by three-point bending experiments. This demonstrates that the composite beam offers equivalent stiffness and strength properties with a weight-reduction potential of nearly 50% for bending loads.

Elektrostatische Greifersysteme für den Leichtbau*/Electrostatic grippers for lightweight productions - Form- and area-adaptive electrostatic gripper systems for high-performance materials

In der Herstellung von Leichtbaukomponenten aus faserverstärkten Kunststoffen treten Handhabungsvorgänge mit empfindlichen, luftdurchlässigen, biegeschlaffen Materialien auf. Um diese Vorgänge in der Produktion etwa in RTM (Resin Transfer Moulding)-Prozessketten zu automatisieren, hat das Fraunhofer IPT einen Greifer für die Handhabung textiler Materialien entwickelt. Dieser Greifer basiert auf der elektrostatischen Adhäsion und ermöglicht automatisiertes Handhaben und Drapieren textiler Hochleistungsmaterialien.   Handling operations with sensitive non-rigid, air-permeable materials are often found in the production of lightweight products made out of fiber-reinforced plastics. In order to further automate the production of light-weight components, for instance in RTM-process-chains, Fraunhofer IPT developed a gripping system especially suitable for sensitive textile materials. This gripper is based on the electro-adhesive effect and enables for the automated handling and draping of textile materials.

Pneumatic Muscle Actuated Parallel Asymmetric Gripper System with a Mobile and a Fixed Jaw

Pneumatically actuated gripper systems are frequently used in various applications due to their multiple advantage, and particularly to their specific feature known as compliance. This is what allows manipulation of fragile objects and ensures their soft contact with the gripper jaws. The paper presents and discusses such a gripper system actuated by a pneumatic muscle. Structural, constructive and functional models of a novel gripper system are presented and its main motion characteristics highlighted.