scholarly journals Analysis of Soft Robotics Based on the Concept of Category of Mobility

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Hayato Saigo ◽  
Makoto Naruse ◽  
Kazuya Okamura ◽  
Hirokazu Hori ◽  
Izumi Ojima
Keyword(s):  
Category Theory ◽  
Soft Materials ◽  
Design Principles ◽  
Theoretical Background ◽  
Rigid Bodies ◽  
The Body ◽  
Soft Robotics ◽  
Soft Robots ◽  
Natural Processes ◽  
Rigorous Description

Soft robotics is an emerging field of research where the robot body is composed of flexible and soft materials. It allows the body to bend, twist, and deform to move or to adapt its shape to the environment for grasping, all of which are difficult for traditional hard robots with rigid bodies. However, the theoretical basis and design principles for soft robotics are not well-founded despite their recognized importance. For example, the control of soft robots is outsourced to morphological attributes and natural processes; thus, the coupled relations between a robot and its environment are particularly crucial. In this paper, we propose a mathematical foundation for soft robotics based on category theory, a branch of abstract mathematics where any notions can be described by objects and arrows. It allows for a rigorous description of the inherent characteristics of soft robots and their relation to the environment as well as the differences compared to conventional hard robots. We present a notion called the category of mobility to well describe the subject matter. The theory has been applied to a model system and analysis to highlight the adaptation behavior observed in universal grippers, which are a typical example of soft robotics. The aim of the present study is not to offer concrete engineering solutions to existing robotics but to provide clear mathematical description of soft robots by category theory and to imply its potential abilities by a simple soft gripper demonstration. This paper paves the way to developing a theoretical background and design principles for soft robotics.

scholarly journals Well, Actuate(ly)...: Parametric Multi-Material 3D Printed Soft Robotics

2021 ◽  
Author(s):  
Patrick Coulson
Keyword(s):  
Complex Geometry ◽  
Casting Process ◽  
Soft Materials ◽  
Research Field ◽  
Soft Robotics ◽  
Soft Robots ◽  
3D Print ◽  
Parametric Control ◽  
3D Printed ◽  
Polyjet Printing

<b>In recent years, soft robotics has gained wide interest in the research field and has also garnered some commercial success. This is because soft robots are comprised of soft materials that have inherent compliance which lends them to a wide variety of applications that are not suited to traditional hard-bodied robots. </b><p>Soft robots are generally created using a casting process, which comes with limitations to the geometry due to the removal of the cast body from the mould. This research seeks to enhance the capabilities of soft robotic limbs using multi-material Polyjet printing – a recently developed additive manufacturing technology – which allows for geometric freedom and variable materials within a singular soft 3D print which is not feasible using other fabrication methods. </p> <p>This research draws inspiration from natural mechanisms such as muscular hydrostats, to enable the exploration of singular channel soft robots that exhibit bending, twisting, elongation, and expansion all in one 3D print. The geometric freedom and variable materiality of the Stratasys J750 produce actuation results for each motion that cannot be easily replicated using traditional fabrication techniques. The printable materials of the Stratasys J750 were found to have tendencies to tear upon inflation, however, a large array of prints with complex geometry were able to successfully actuate despite this. In some areas, results outperformed actuators made using other fabrication techniques, as was particularly evident in the twisting actuators. Through fine-tuned parametric control with equation-driven modelling, this portfolio presents a method for soft robotic design and construction that can produce a limb with multiple motions and up to 5 axes of movement that can be tailored to specific pre-defined applications.</p>

scholarly journals Soft Adaptive Mechanical Metamaterials

2021 ◽  
Vol 8 ◽  
Author(s):  
Romik Khajehtourian ◽  
Dennis M. Kochmann
Keyword(s):  
Soft Materials ◽  
Building Blocks ◽  
Soft Robotics ◽  
Energy Potential ◽  
Soft Robots ◽  
Strongly Nonlinear ◽  
Mechanical Metamaterials ◽  
Unit Cells ◽  
Potential Applications ◽  
Mechanical Logic

Soft materials are inherently flexible and make suitable candidates for soft robots intended for specific tasks that would otherwise not be achievable (e.g., smart grips capable of picking up objects without prior knowledge of their stiffness). Moreover, soft robots exploit the mechanics of their fundamental building blocks and aim to provide targeted functionality without the use of electronics or wiring. Despite recent progress, locomotion in soft robotics applications has remained a relatively young field with open challenges yet to overcome. Justly, harnessing structural instabilities and utilizing bistable actuators have gained importance as a solution. This report focuses on substrate-free reconfigurable structures composed of multistable unit cells with a nonconvex strain energy potential, which can exhibit structural transitions and produce strongly nonlinear transition waves. The energy released during the transition, if sufficient, balances the dissipation and kinetic energy of the system and forms a wave front that travels through the structure to effect its permanent or reversible reconfiguration. We exploit a triangular unit cell’s design space and provide general guidelines for unit cell selection. Using a continuum description, we predict and map the resulting structure’s behavior for various geometric and material properties. The structural motion created by these strongly nonlinear metamaterials has potential applications in propulsion in soft robotics, morphing surfaces, reconfigurable devices, mechanical logic, and controlled energy absorption.

scholarly journals Soft robotics: the route to true robotic organisms

2021 ◽  
Author(s):  
Jonathan Rossiter
Keyword(s):  
Environmental Impact ◽  
Soft Materials ◽  
Soft Robotics ◽  
Biodegradable Materials ◽  
Soft Robots ◽  
Soft Systems ◽  
Biological Organisms ◽  
The Way

AbstractSoft Robotics has come to the fore in the last decade as a new way of conceptualising, designing and fabricating robots. Soft materials empower robots with locomotion, manipulation, and adaptability capabilities beyond those possible with conventional rigid robots. Soft robots can also be made from biological, biocompatible and biodegradable materials. This offers the tantalising possibility of bridging the gap between robots and organisms. Here, we discuss the properties of soft materials and soft systems that make them so attractive for future robots. In doing so, we consider how future robots can behave like, and have abilities akin to, biological organisms. These include huge numbers, finite lifetime, homeostasis and minimal—and even positive—environmental impact. This paves the way for future robots, not as machines, but as robotic organisms.

scholarly journals Well, Actuate(ly)...: Parametric Multi-Material 3D Printed Soft Robotics

2021 ◽  
Author(s):  
Patrick Coulson
Keyword(s):  
Complex Geometry ◽  
Casting Process ◽  
Soft Materials ◽  
Research Field ◽  
Soft Robotics ◽  
Soft Robots ◽  
3D Print ◽  
Parametric Control ◽  
3D Printed ◽  
Polyjet Printing

<b>In recent years, soft robotics has gained wide interest in the research field and has also garnered some commercial success. This is because soft robots are comprised of soft materials that have inherent compliance which lends them to a wide variety of applications that are not suited to traditional hard-bodied robots. </b><p>Soft robots are generally created using a casting process, which comes with limitations to the geometry due to the removal of the cast body from the mould. This research seeks to enhance the capabilities of soft robotic limbs using multi-material Polyjet printing – a recently developed additive manufacturing technology – which allows for geometric freedom and variable materials within a singular soft 3D print which is not feasible using other fabrication methods. </p> <p>This research draws inspiration from natural mechanisms such as muscular hydrostats, to enable the exploration of singular channel soft robots that exhibit bending, twisting, elongation, and expansion all in one 3D print. The geometric freedom and variable materiality of the Stratasys J750 produce actuation results for each motion that cannot be easily replicated using traditional fabrication techniques. The printable materials of the Stratasys J750 were found to have tendencies to tear upon inflation, however, a large array of prints with complex geometry were able to successfully actuate despite this. In some areas, results outperformed actuators made using other fabrication techniques, as was particularly evident in the twisting actuators. Through fine-tuned parametric control with equation-driven modelling, this portfolio presents a method for soft robotic design and construction that can produce a limb with multiple motions and up to 5 axes of movement that can be tailored to specific pre-defined applications.</p>

Ciało poza Człowiekiem, czyli Ciało Wyemancypowane w ujęciu Elizabeth Grosz

2012 ◽  
Author(s):  
Monika Rogowska-Stangret
Keyword(s):  
Women's Movement ◽  
Ways Of Knowing ◽  
Theoretical Background ◽  
The Body ◽  
Human Being ◽  
Biological Aspect ◽  
Theory Of Evolution

The article presents the philosophy of Elizabeth Grosz, its theoretical background and methods. It concentrates mainly on the category of the body which is present in her thought from the very beginning. The author pays particular attention to the problem of materiality of the body raised in The Nick of Time and Time Travels: why is the body docile? What makes it so vulnerable? What precedes social inscriptions? Those questions underline the problem of the biological aspect of the body as a part of nature which comes together with Grosz's interpretation of Darwin. The theory of evolution shows the temporality of human being and its culture and introduces future possibilities of overcoming the humankind and creating new ways of knowing, new sexes, new forms of living etc. The author suggests that this understanding of the body takes us beyond the human being and beyond subjectivity, it faces us with the process of becoming different which is perceived as emancipating. The author also suggests that Grosz's idea of the politics of imperceptibility is close to Foucault's recognition of the value of women's movement which, in his opinion, lies not in identity struggles but above all in struggles concentrating on broader cultural, social etc. changes. Both Foucault and Grosz aim at potential practices that involve giving up the question of our identities.

scholarly journals B-Spline Impulse Response Functions of Rigid Bodies for Fluid-Structure Interaction Analysis

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
S. Zhou-Bowers ◽  
D. C. Rizos
Keyword(s):  
Impulse Response ◽  
Dynamic Models ◽  
Interaction Analysis ◽  
Fluid Structure Interaction ◽  
Rigid Bodies ◽  
The Body ◽  
Impulse Response Functions ◽  
Fluid Structure ◽  
B Spline ◽  
Structure Interaction

Reduced 3D dynamic fluid-structure interaction (FSI) models are proposed in this paper based on a direct time-domain B-spline boundary element method (BEM). These models are used to simulate the motion of rigid bodies in infinite or semi-infinite fluid media in real, or near real, time. B-spline impulse response function (BIRF) techniques are used within the BEM framework to compute the response of the hydrodynamic system to transient forces. Higher-order spatial and temporal discretization is used in developing the kinematic FSI model of rigid bodies and computing its BIRFs. Hydrodynamic effects on the massless rigid body generated by an arbitrary transient acceleration of the body are computed by a mere superposition of BIRFs. Finally, the dynamic models of rigid bodies including inertia effects are generated by introducing the kinematic interaction model to the governing equation of motion and solve for the response in a time-marching scheme. Verification examples are presented and demonstrate the stability, accuracy, and efficiency of the proposed technique.

Design and Characterization of Edible Soft Robotic Candy Actuators

MRS Advances ◽  
2018 ◽  
Vol 3 (50) ◽  
pp. 3003-3009 ◽  
Author(s):  
Aditya N. Sardesai ◽  
Xavier M. Segel ◽  
Matthew N. Baumholtz ◽  
Yiheng Chen ◽  
Ruhao Sun ◽  
...  
Keyword(s):  
High School ◽  
The Body ◽  
Soft Robotics ◽  
Compression Tests ◽  
Pneumatic Actuators ◽  
School Division ◽  
Biologically Relevant ◽  
Elementary Aged Children ◽  
Design Competition ◽  
Robotic Devices

ABSTRACTOne of the goals of soft robotics is the ability to interface with the human body. Traditionally, silicone materials have dominated the field of soft robotics. In order to shift to materials that are more compatible with the body, developments will have to be made into biodegradable and biocompatible soft robots. This investigation focused on developing gummy actuators which are biodegradable, edible, and tasty. Creating biodegradable and edible actuators can be both sold as an interactive candy product and also inform the design of implantable soft robotic devices. First, commercially available gelatin-based candies were recast into pneumatic actuators utilizing molds. Edible robotic devices were pneumatically actuated repeatedly (up to n=8 actuations) using a 150 psi power inflator. To improve upon the properties of actuators formed from commercially available candy, a novel gelatin-based formulation, termed the “Fordmula” was also developed and used to create functional actuators. To investigate the mechanics and functionality of the recast gummy material and the Fordmula, compression testing and biodegradation studies were performed. Mechanical compression tests showed that recast gummy materials had similar properties to commercially available candies and at low strain had similar behavior to traditional silicone materials. Degradation studies showed that actuation was possible within 15 minutes in a biologically relevant solution followed by complete dissolution of the actuator afterwards. A taste test with elementary aged children demonstrated the fun, edible, and educational appeal of the candy actuators. Edible actuator development was an entry and winning submission in the High School Division of the Soft Robotics Toolkit Design Competition hosted by Harvard University. Demonstration of edible soft robotic actuators created by middle and high school aged students shows the applicability of the Soft Robotics Toolkit for K12 STEM education.

scholarly journals O Futuro de Soft Robotics: Uma Revisão Bibliográfica

2019 ◽  
Author(s):  
Paulo Dos Santos ◽  
Guilherme Da Silva ◽  
Juliana Silva
Keyword(s):  
Soft Robotics ◽  
Review Of The Literature ◽  
Soft Robots ◽  
Medical Area ◽  
The Future

This study seeks to explain a new theme that has a potential of great impact in the future. Soft robots are robots that, because they are soft and not limited by their axes, can go beyond how rigid robots work. The objective of this study is to present a review of the literature on soft robots. The literature shows little research on these robots, presenting difficulties mainly in the research of sensors and materials to be used in their construction. Despite the difficulties, the increase of research with this approach will have great impacts, mainly in the medical area.

A Semi-Discrete Approach for the Numerical Simulation of Freestanding Blocks

2016 ◽  
pp. 416-439
Author(s):  
Fernando Peña
Keyword(s):  
Differential Equation ◽  
Numerical Simulation ◽  
Numerical Modeling ◽  
Discrete Model ◽  
Mathematical Formulation ◽  
Equation Of Motion ◽  
Rigid Bodies ◽  
The Body ◽  
Discrete Approach ◽  
Rocking Motion

This chapter addresses the numerical modeling of freestanding rigid blocks by means of a semi-discrete approach. The pure rocking motion of single rigid bodies can be easily studied with the differential equation of motion, which can be solved by numerical integration or by linearization. However, when we deal with sliding and jumping motion of rigid bodies, the mathematical formulation becomes quite complex. In order to overcome this complexity, a Semi-Discrete Model (SMD) is proposed for the study of rocking motion of rigid bodies, in which the rigid body is considered as a mass element supported by springs and dashpots, in the spirit of deformable contacts between rigid blocks. The SMD can detect separation and sliding of the body; however, initial base contacts do not change, keeping a relative continuity between the body and its base. Extensive numerical simulations have been carried out in order to validate the proposed approach.

Hovering of a rigid pyramid in an oscillatory airflow

2010 ◽  
Vol 650 ◽  
pp. 415-425 ◽  
Author(s):  
ANNIE WEATHERS ◽  
BRENDAN FOLIE ◽  
BIN LIU ◽  
STEPHEN CHILDRESS ◽  
JUN ZHANG
Keyword(s):  
Body Mass ◽  
Rigid Bodies ◽  
The Body ◽  
The Asymmetry

We investigate the dynamics of rigid bodies (hollow ‘pyramids’) placed within a background airflow, oscillating with zero mean. The asymmetry of the body introduces a net upward force. We find that when the amplitude of the airflow is above a threshold, the net lift exceeds the weight and the object starts to hover. Our results show that the objects hover at far smaller air amplitudes than would be required by a quasi-steady theory, although this theory accounts qualitatively for the behaviour of the system as the body mass becomes small.

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