Evolutionary Fabrication: An Autonomous System of Invention

Evolutionary algorithms have had success in designing complex objects, ranging from antennae used in NASA\u27s Space Technology 5 mission to astronomical telescope lenses. However, evolutionary design is limited by the ability of a simulation to accurately represent the physical world. Addition-ally, evolved designs may be well described, but they carry no set of speci˝c instructions describing how to physically create such a design. Evolutionary Fabrication (EvoFab) recti˝es this: EvoFab is a machine built upon a process that can, in principle, automatically invent and build anything, from soft robots to new toys, by evolving the process, not the product. We have designed EvoFab, which consists of four components: A) a genotype for printing objects, consisting of a linear set of instructions sent to a Fab@Home, an open-source 3D printer; B) a way to evaluate printed objects using custom machine vision algorithms; C) a way to automate printing by implementing a cus-tom conveyor belt; D) a way of elaborating upon designs by implementing a genetic algorithm. In the near term, we aim to produce an evolved arch. Current results indicate increased ˝tness over time. Future improvements are possible through restrictions in extrusion along the Y-axis as well as re˝ning ˝tness evaluation to be less exploitable

Effective ANN Topologies for Use as Genotypes for Evaluating Design and Fabrication

There is promise in the field of Evolutionary Design for systems that evolve not only what to manufacture but also how to manufacture it. EvoFab is a system that uses Genetic Algorithms to evolve Artificial Neural Networks (ANNs) which control a modified 3d-printer with the goal of automating some level of invention. ANNs are an obvious choice for use with a system like this as they are canonically evolvable encodings, and have been successfully used as evolved control systems in Evolutionary Robotics. However, there is little known about how the structural characteristics of an ANN affect the shapes that can be produced when that ANN controls a system like a 3d-printer. We consider the relationship between certain structural characteristics of an ANN and the ability of that ANN to produce complex geometric shapes by controlling a 3d-printer. We develop an understanding of shape complexity for 2d shapes in a simulated 3d-printer in order to use Genetic Algorithms to optimize ANNs with fixed structures to produce complex outputs and assess the relationship between topologies of ANNs and the systems success in producing complex outputs under evolutionary optimization

Morphological Evolution of Physical Robots through Model-Free Phenotype Development.

Artificial evolution of physical systems is a stochastic optimization method in which physical machines are iteratively adapted to a target function. The key for a meaningful design optimization is the capability to build variations of physical machines through the course of the evolutionary process. The optimization in turn no longer relies on complex physics models that are prone to the reality gap, a mismatch between simulated and real-world behavior. We report model-free development and evaluation of phenotypes in the artificial evolution of physical systems, in which a mother robot autonomously designs and assembles locomotion agents. The locomotion agents are automatically placed in the testing environment and their locomotion behavior is analyzed in the real world. This feedback is used for the design of the next iteration. Through experiments with a total of 500 autonomously built locomotion agents, this article shows diversification of morphology and behavior of physical robots for the improvement of functionality with limited resources.This study was supported by the Swiss National Science Foundation Grant No. PP00P2123387/1 and the ETH Zurich Research Grant ETH-23-10-3. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.This is the final version of the article. It first appeared from [publisher] via http://dx.doi.org/1371/journal.pone.012844

Development of a toolhead for fused filament extrusion applied to additive manufacturing

Orientador: João Maurício RosárioDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia MecânicaResumo: O processo mais difundido de Manufatura Aditiva baseia-se no princípio da deposição de termoplástico fundido e extrudado por um bico. Grande parte dos equipamentos comerciais de Manufatura Aditiva é de projeto fechado e isso dificulta sua aplicação em pesquisas, sobretudo na área de biofabricação, no entanto, outra linha de equipamentos vem surgindo com iniciativa de projetos de código aberto que permitem livremente a sua modificação para aplicações específicas. Este trabalho apresenta o desenvolvimento de um cabeçote para Manufatura Aditiva baseado na extrusão de filamento fundido, que permite o uso de diversos polímeros termoplásticos na máquina de código aberto Fab@CTI. A metodologia do desenvolvimento constituiu de melhorias sucessivas de projetos. A concepção preliminar do cabeçote se deu por meio dos requisitos de usuário e de projeto e outras duas versões foram criadas como conseqüência das melhorias implementadas. Foi dado foco maior na região aquecida a fim de possibilitar o uso do maior número de polímeros possível. O cabeçote desenvolvido permite extrudar materiais termoplásticos com diferentes pontos de fusão e diferentes diâmetros de filamento (1,8 mm à 3,0 mm). Para pesquisa na fabricação de scaffolds, o cabeçote mostrou-se funcional para os polímeros policaprolactona, poli(ácido) lático e polihidroxibutirato, os quais foram estruturados tridimensionalmente com poros a partir de 250 µm e camada mínima de 0,3 mm. A extrusão do acrilonitrila butadieno estireno se mostrou desafiadora e exige maiores investigações embora tenha-se impresso algumas geometrias. Conclui-se que o cabeçote desenvolvido neste trabalho se mostrou funcional, permitindo o processamento de polímeros termoplásticos e estruturar geometrias tridimensionaisAbstract: The most widespread Additive Manufacturing process is based on the principle of deposition of thermoplastic extruded through a nozzle. Much of the commercial Additive Manufacturing equipment are closed project and this complicates its application in research, especially in the field of biomanufacturing, however, a line of equipment with open source projects, allows the free modification for a specific applications. This work shows the development of an Additive Manufacture toolhead based on the fused deposition thermoplastic, which allows the use of various thermoplastics polymers in the open source platform Fab@CTI machine. The development methodology consisted of successive improvements projects. The preliminary design of the toolhead was through the user and design requirements. Two others versions were created as a result of the improvements implemented. Greater focus has been given in the heated region to enable the use of the largest number of polymers as possible. The toolhead developed is able to extrude thermoplastic materials with different melting points and different filament diameters (1.8 mm to 3.0 mm). For the research in scaffolds, the toolhead proved functional for polycaprolactone polymers and polyhydroxybutyrate polylactic acid, which were three dimensionally structured with pore size of 250 micrometers and a minimum of 0,3 mm layer. The extrusion of acrylonitrile butadiene styrene was challenging and requires further investigation although some geometries were printed. It was concluded that the head developed in this study proved to be viable and successfully met its proposal, to process thermoplastic polymers with three-dimensional geometries. Although it was originally developed for the Fab@CTI platform, the system is possible to be adapted to other machinesMestradoMecanica dos Sólidos e Projeto MecanicoMestre em Engenharia Mecânic

Automatically Designing and Printing 3-D Objects with EvoFab 0.2

Although Evolutionary Design has had great success in creating virtual objects, very few of these evolved designs have been manufactured. Standing in the way is the fabrication gap caused by a reliance on prescriptive rather than descriptive representations of evolved objects. Evolutionary Fabrication describes an alternative process which evolves how rather than what to build. In this paper we describe EvoFab 0.2, a completely automated physically embodied machine which implements Evolutionary Fabrication and evolves three dimensional objects. We describe the mechanism and underlying algorithms in detail, and show how it can be used to create novel structures

Never Too Old To Learn: On-line Evolution of Controllers in Swarm- and Modular Robotics

Eiben, A.E. [Promotor