Exploring Convergence of Snake Skin-Inspired Texture Designs and Additive Manufacturing for Mechanical Traction

This research focuses on the understanding, development, and additive manufacture of a 3D printed snake skin-inspired texture pattern. The design functionalities of snake skin were determined through the study of the snake species Python Regius otherwise known as the ball python. Each scale of a snake has hierarchical texture with hexagonal macro-patterns aligned on the ventral surface of the skin with overriding anisotropic micro textured patterns such as denticulations and fibrils. Using a laser-powder bed fusion (L-PBF) process, 420 stainless steel samples were 3D printed which closely resemble the above described directional texture of natural snake skin. This printed surface was tested for the understanding of friction management using a pin-on-disk tribometer in relation to the directional antislippery behavior of the snake. This thesis explores the convergence of a bio-inspired design with additive manufacturing for realization of functional surfaces

Modeling and simulation in tribology across scales: An overview

This review summarizes recent advances in the area of tribology based on the outcome of a Lorentz Center workshop surveying various physical, chemical and mechanical phenomena across scales. Among the main themes discussed were those of rough surface representations, the breakdown of continuum theories at the nano- and micro-scales, as well as multiscale and multiphysics aspects for analytical and computational models relevant to applications spanning a variety of sectors, from automotive to biotribology and nanotechnology. Significant effort is still required to account for complementary nonlinear effects of plasticity, adhesion, friction, wear, lubrication and surface chemistry in tribological models. For each topic, we propose some research directions

Kinematics and Robot Design I, KaRD2018

This volume collects the papers published on the Special Issue “Kinematics and Robot Design I, KaRD2018” (https://www.mdpi.com/journal/robotics/special_issues/KARD), which is the first issue of the KaRD Special Issue series, hosted by the open access journal “MDPI Robotics”. The KaRD series aims at creating an open environment where researchers can present their works and discuss all the topics focused on the many aspects that involve kinematics in the design of robotic/automatic systems. Kinematics is so intimately related to the design of robotic/automatic systems that the admitted topics of the KaRD series practically cover all the subjects normally present in well-established international conferences on “mechanisms and robotics”. KaRD2018 received 22 papers and, after the peer-review process, accepted only 14 papers. The accepted papers cover some theoretical and many design/applicative aspects

Processo para medição e avaliação de atrito com fins de facilitar movimentação de robô ápode

Trabalho de Conclusão de Curso (graduação)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Mecânica, 2018.Todos os seres vivos são resultados de um processo de validação e otimização de, no mínimo, milhares de anos, período de testes superior à quaisquer teorias ou mecanismos desenvolvidos por seres humanos. Por isso, o uso de tecnologias bioinspiradas é algo até óbvio, principalmente em situações onde animais tem desempenho melhor do que máquinas tradicionais, como busca e salvamento de sobreviventes em destroços. Em verdade, já existe na literatura uma série de projetos de robôs bioinspirados em cobras, os quais buscam fazer uso do estilo de locomoção de fácil equilíbrio do animal e sua adaptabilidade a diversos terrenos. Contudo, a existência de tais projetos não significa nem sua aplicação prática de maneira satisfatória nem o melhor uso das possibilidades que estes trazem, o que se explica em parte pelo fato de muitos dos robôs presentes na literatura sofrem do mesmo mal: a falta do estudo adequado sobre os efeitos do atrito na movimentação e de como o tornar útil. Uma falha que poderia ser perdoada em vários projetos que não exijam precisão fina de deslocamento, mas que traz perdas de informação e otimização enquanto considerados robôs inspirados em cobras. Nada na natureza é por acaso, e se estes animais possuem acabamentos superficiais nanométricos em suas escamas ventrais diferentes dos observados em suas escamas dorsais, os quais alteram o coeficiente de atrito em três direções das escamas, há uma razão por trás. E é por essa lógica que o principal objetivo deste trabalho não foi desenvolver soluções inovadoras para melhorar a movimentação dos ditos robôs cobra, mas sim buscar respostas simples que tenham ficado pra trás durante a evolução destes. Como por exemplo, a explicação lógica e física do porquê as cobras enrolam seus corpos enquanto de movem e como esse fenômeno pode ser aplicado. Em suma, para se seguir adiante em robôs cobra com aplicação melhor e mais ampla, esse trabalho propõe olhar para trás, para o começo. Foram selecionadas três frentes de desenvolvimento: geometria e morfologia do robô, desenho e teste de escamas artificiais e determinação de uma rotina baseada em relações trigonométricas através da qual um robô seja capaz de obter um senso quanto ao atrito do terreno onde se encontre. Todas as três etapas pediram por um estudo morfológico e físico de robótica modular, movimentação cobra, anatomia e comportamento de cobras além de definições quanto ao fenômeno de atrito e seus modelos. Com isso, a presença de uma extensa revisão bibliográfica em diferentes conteúdos foi inevitável, porém os resultados foram mais que satisfatórios, enquanto compostos por uma validação quanto a aplicabilidade de soluções simples bioinspiradas, as quais podem ser aplicadas à quaisquer robôs com movimentação cobra.All living beings are the result of a validation and optimization process of at least thousands of years, to superior test period than any mechanism or theory developed by humans. Therefore, the use of bioinspired technologies is obvious, especially in conditions where animals have better performance than traditional machinery, such as search and rescue of survivors in accident debris. In fact, the already exist to sieries of projects the snake inspired robots in literature, whose made use of the stable locomotion gait of the animal and it’s adaptability to unknow terrain. However, the existence of such project does not translate into it’s optimal application nor in the better use of it’s inehenrent possibilities, what can be explained in part by tha fact that most of the robots found in the literature commit the same sin: the lack of a proper study about friction effects on locomotion and how to make it valuable. A mistake that could be forgiven in most projects that do not call for fine movement precision, but that causes loss of information and optimization while considering snake bioinspired robots. Nothing is done in nature without a reason, and if those animals have nanometric superficial characteristics in it’s ventral scales that are different from it’s dorsal ones, and if those characteristics alter the scale friction coefficiente in three different directions, there is a reason behind it. And this is why the main objective of this work was not to develop a brand new solution to optimize the locomotion of so said robots, but rather look for simple answers that have been left behing during the robots evolution. For example, the logical and physical reason for why they snake wrap their bodies during it’s movement and how this phenomenon can be applied. In short, to move ahead with snake robots with a better and wider application, this work proposes to look back, to the starter point. Three development fronts where selected: geometry and morphology of the robot, design and test of artificial scales and determination of the routine based on trigomometric relations such that it allows the robot to get a sense of the it’s terrain friction. All three fronts required a morphological and physic studie of modular robotics, snake locomotion, snake anatomy and behavior as well as definitions of the friction phenomena and it’s models. With that, the presence of an extense literature review was inescapable, but the results here are more satisfactory, while presentis to validation of the applicability of simple bioispires solutions that can be applied in any robot with snake locomotion

Engineering derivatives from biological systems for advanced aerospace applications

The present study consisted of a literature survey, a survey of researchers, and a workshop on bionics. These tasks produced an extensive annotated bibliography of bionics research (282 citations), a directory of bionics researchers, and a workshop report on specific bionics research topics applicable to space technology. These deliverables are included as Appendix A, Appendix B, and Section 5.0, respectively. To provide organization to this highly interdisciplinary field and to serve as a guide for interested researchers, we have also prepared a taxonomy or classification of the various subelements of natural engineering systems. Finally, we have synthesized the results of the various components of this study into a discussion of the most promising opportunities for accelerated research, seeking solutions which apply engineering principles from natural systems to advanced aerospace problems. A discussion of opportunities within the areas of materials, structures, sensors, information processing, robotics, autonomous systems, life support systems, and aeronautics is given. Following the conclusions are six discipline summaries that highlight the potential benefits of research in these areas for NASA's space technology programs