Survey on model-based manipulation planning of deformable objects

A systematic overview on the subject of model-based manipulation planning of deformable objects is presented. Existing modelling techniques of volumetric, planar and linear deformable objects are described, emphasizing the different types of deformation. Planning strategies are categorized according to the type of manipulation goal: path planning, folding/unfolding, topology modifications and assembly. Most current contributions fit naturally into these categories, and thus the presented algorithms constitute an adequate basis for future developments.Preprin

Modeling, Simulation, and Validation of Process-Structure-Property Relationships in Fused Filament Fabrication

As additive manufacturing (AM) grows in popularity, the need for better simulation tools to predict the process-structure-property relationships of AM parts becomes ever more necessary to employ the technology in design of functional parts with varying degrees of complexity and performance requirements. Many simulation tools and techniques have been developed that aim to achieve this goal, and the main purpose of this research is to explore how well different simulation tools and modeling approaches can capture various AM-specific features such as inter-raster and end-of raster voids, and residual stresses induced by dissimilar rates of thermal expansion. Process simulation of fused filament fabrication (FFF) through FEA-based code (ABAQUS) and affiliated programs combined with performance simulation through a nonlinear user-material model (GENOA) to predict the tensile and bending properties of Polylactic Acid (PLA) samples. Following the examination of different process parameters such as rate of extrusion per distance travel, fan speed, and nozzle temperature through a multi-factor design of experiments, an optimal setting was identified and used to explore the effect of raster architecture on tensile response of dog-bone specimens based on ASTM D638 standard, and bending response of rectangular beam specimens based on ASTM D790 standard. Comparison of the experimental data from nearly 300 tests with the simulation-based results indicate that the Young’s modulus, ultimate tensile strength, and bending strength predictions are very sensitive to how FFF-induced voids and temperature effects are modeled, and that it is possible to achieve reasonably good agreements