In this paper we present a model in which the motions of two families of beams constituting a pantographic sheet, when described with two independent placement fields, allows to correctly simulate the points of fracture onset in axial tension test. The deformation energy is postulated in function of these independent displacements as involving an additive quadratic term of deformation energy depending on the squared norm of their difference. The first performed numerical simulations establish that the most strained pivots are exactly the ones where one observes the first rupture

For certain additive manufacturing technologies the choice of available materials is currently limited. The development of process parameters is especially elaborate for powder bed technologies. Currently, there is no common approach concerning the procedure and documentation. This work proposes a methodology for the initial development of process parameters for new L-PBF (laser powder bed fusion) alloys. Key elements are the examination of the laser–powder-bed interaction by single laser track experiments and an iterative design of experiment (DoE) approach for the development of volumetric parameters. Two types of single laser track experiments are presented and provide information regarding the laser track width and depth as well as the resulting surface roughness and melt pool classification. Based on the information gained, suitable process windows for a DoE study can be defined by avoiding parameter settings unsuitable for production or measurement. Gradually, input variables are identified and iterative steps reduce the process window in order to optimize the desired target values. Near-surface exposure parameters are developed by a one-dimensional parameter variation and metallographic investigations. The approach is primarily designed for the initial development of process parameters for new L-PBF alloys. However, the information gained can also be used to optimize established parameter sets regarding new target values (productivity, mechanical properties), optimize process parameters for specific components or for a microstructural design.

The next step in minimally invasive surgery is the further reduction of incisions by surgery through natural orifices (NOTES) or one single artificial incision (Single-Port). However, physicians pointed out, that those procedures are only possible if new technologies will increase the dexterity of the instruments inside of the body. Especially the missing ability to manipulate tissue from two sides (triangulation), needs to be obtained. This article is about the development of different kinematics for a Multi Arm Snake-Like Robot to manipulate flexible endoscopic instruments at the tip of a flexible endoscope. By using Selective Laser Sintering (SLS) it is feasible to create various shapes and designs, custom made for different patients. We are using flexure hinges and compliant mechanisms to create defined movements in serial kinematic structures. In the experiments, the relation between different structures and the influence of the inserted flexible endoscopic instrument are compared. The proposed kinematics are able to manipulate flexible endoscopic instruments. That proves that SLS structures get more advances towards a use for a flexible Single-Port Multi Arm Snake-Like Robot.