Procedural band patterns

We seek to cover a parametric domain with a set of evenly spaced bands which number and widthvaries according to a density field. We propose an implicit procedural algorithm, that generates theband pattern from a pixel shader and adapts to changes to the control fields in real time. Each band isuniquely identified by an integer. This allows a wide range of texturing effects, including specifying adifferent appearance in each individual bands. Our technique also affords for progressive gradationsof scales, avoiding the abrupt doubling of the number of lines of typical subdivision approaches. Thisleads to a general approach for drawing bands, drawing splitting and merging curves, and drawingevenly spaced streamlines. Using these base ingredients, we demonstrate a wide variety of texturingeffects

Procedural band patterns

International audienceWe seek to cover a parametric domain with a set of evenly spaced bands which number and widthvaries according to a density field. We propose an implicit procedural algorithm, that generates theband pattern from a pixel shader and adapts to changes to the control fields in real time. Each band isuniquely identified by an integer. This allows a wide range of texturing effects, including specifying adifferent appearance in each individual bands. Our technique also affords for progressive gradationsof scales, avoiding the abrupt doubling of the number of lines of typical subdivision approaches. Thisleads to a general approach for drawing bands, drawing splitting and merging curves, and drawingevenly spaced streamlines. Using these base ingredients, we demonstrate a wide variety of texturingeffects

A brick in the wall: Staggered orientable infills for additive manufacturing

International audienceAdditive manufacturing is typically conducted in a layer-by-layer fashion. A key step of the process is to define, within each planar layer, the trajectories along which material is deposited to form the final shape. The direction of these trajectories triggers an anisotropy in the fabricated parts, which directly affects their properties, from their mechanical behavior to their appearance. Controlling this anisotropy paves the way to novel applications, from stronger parts to controlled deformations and surface patterning.This work introduces a method to generate trajectories that precisely follow an input direction field while simultaneously avoiding intra- and inter-layer defects. Our method results in spatially coherent trajectories - all follow the specified direction field throughout the layers - while providing precise control over their inter-layer arrangement. This allows us to generate a staggered layout of trajectories across layers, preventing unavoidable tiny gaps from forming tunnel-shaped voids throughout a part volume.Our approach is simple, robust, easy to implement, and scales linearly with the input volume. It builds upon recent results in procedural generation of oscillating patterns, generating a signal in the 3D domain that oscillates with a frequency matching the deposition beads width while following the input direction field. Trajectories are extracted with a process akin to a marching square

CurviSlicer: Slightly curved slicing for 3-axis printers

International audienceMost additive manufacturing processes fabricate objects by stacking planar layers of solidified material. As a result, produced parts exhibit a so-called staircase effect, which results from sampling slanted surfaces with parallel planes. Using thinner slices reduces this effect, but it always remains visible where layers almost align with the input surfaces. In this research we exploit the ability of some additive manufacturing processes to deposit material slightly out of plane to dramatically reduce these artifacts. We focus in particular on the widespread Fused Filament Fabrication (FFF) technology, since most printers in this category can deposit along slightly curved paths, under deposition slope and thickness constraints. Our algorithm curves the layers, making them either follow the natural slope of the input surface or on the contrary, make them intersect the surfaces at a steeper angle thereby improving the sampling quality. Rather than directly computing curved layers, our algorithm optimizes for a deformation of the model which is then sliced with a standard planar approach. We demonstrate that this approach enables us to encode all fabrication constraints , including the guarantee of generating collision-free toolpaths, in a convex optimization that can be solved using a QP solver. We produce a variety of models and compare print quality between curved deposition and planar slicing

Spatial 3D printing methods

Tato bakalářská práce pojednává o metodách prostorového 3D tisku, pomocí nichž je možné řešit řadu problémů, které se k výrobě vytlačováním nataveného termoplastu vážou. Cílem textu je tyto metody přiblížit čtenáři a seznámit ho s jejich silnými a slabými stránkami, požadavky na software, hardware a jejich přínosem pro oblast 3D tisku. První část práce se věnuje představení jednotlivých metod, obsahem druhé části je pak jejich kritické zhodnocení a seřazení dle připravenosti řešit problémy technické praxe.This bachelor's thesis deals with methods of spatial 3D printing, which can solve many problems of manufacturing by fused deposition modelling. The aim of this thesis is to describe their strengths and weaknesses, requirements for hardware, software and their benefits to the world of 3D printing. Methods are introduced in the first part of the thesis, while the final evaluation is placed further.