Geometric optimal control of a snake robot

Tato bakalářská práce se zabývá popisem robotického hada tzv. trident snake robota, který z hlediska teorie řízení patří mezi neholonomní systémy. Řiditelnost robotického hada je určena základními vektorovými poli avšak pro zajištění lokální řiditelnosti systému je nutné pomocí operace Lieova závorka vytvořit další řídící vektorová pole. Dále jsou navrženy základní algoritmy pohybu hada v prostoru. V závěru jsou pak některé z pohybů hada simulovány v prostředí V-rep.This thesis deals with the description of robotic snake the trident snake robot. From a viewpoint of control theory the robot is classified as a nonholonomic system whose controllability is determined by vector fields. We use the operation Lie bracket to create other necessary control vector fields to ensure local controllability of this system. Then we propose the motion planning algorithm. Finally some of the motions caused by the control vector fields are verified in a simulation environment called V-rep.

Geometric approach in robotic snake motion control

Tato diplomová práce se zabývá popisem řiditelnosti specifického robotického hada, který se nazývá trident snake robot. Tento robot je řazen mezi neholonomní systémy. Model je převeden do jazyka diferenciální geometrie a řízen pomocí vektorových polí a operace na nich zavedené (Lieova závorka). Je také uvažována aproximace řídicí distribuce. Dále jsou formulovány pohyby hada ve směru vektorových polí a jejich kombinace, které zajišťují základní pohyby v prostoru (rotace a translace). Tyto pohyby jsou na závěr simulovány v prostředí V-REP.This thesis deals with the description of controllability of a specific robotic snake named trident snake robot. This robot is classified as a nonholonomic system. The kinematics model is converted into the language of differential geometry and controlled by vector fields and their operation Lie bracket. Approximation of the controlling distribution is also considered. Next, vector field motions are described and also their combinations which provide basic planar surface motions (rotation and translation). Finally, these motions caused by vector fields are simulated in V-REP.

Geometrically controlled snake-like robot model

This master’s thesis describes equations of motion for dynamic model of nonholonomic constrained system, namely the trident robotic snakes. The model is studied in the form of Lagrange's equations and D’Alembert’s principle is applied. Actually this thesis is a continuation of the study going at VUT about the simulations of non-holonomic mechanisms, specifically robotic snakes. The kinematics model was well-examined in the work of of Byrtus, Roman and Vechetová, Jana. So here we provide equations of motion and address the motion planning problem regarding dynamics of the trident snake equipped with active joints through basic examples and propose a feedback linearization algorithm.This master’s thesis describes equations of motion for dynamic model of nonholonomic constrained system, namely the trident robotic snakes. The model is studied in the form of Lagrange's equations and D’Alembert’s principle is applied. Actually this thesis is a continuation of the study going at VUT about the simulations of non-holonomic mechanisms, specifically robotic snakes. The kinematics model was well-examined in the work of of Byrtus, Roman and Vechetová, Jana. So here we provide equations of motion and address the motion planning problem regarding dynamics of the trident snake equipped with active joints through basic examples and propose a feedback linearization algorithm.

Foundations of geometric control theory

Táto bakalárska práca sa zaoberá popisom algoritmu riadenia trident snake robota. Jeho model je vytvorený pomocou prostriedkov diferenciálnej geometrie. Ovládateľnosť robota zabezbečuje Lieova algebra, generovaná základnými vektorovými polami a ich Lieovými zátvorkami. Systém je aproximovaný pomocou nilpotentnej aproximácie. V práci je navrhutý a popísaný algoritmus riadenia s počastiach konštantným vstupom. Tento algoritmus je navyše odvodený pre trident snake robota. Nakoniec sú simulované a vykreslené vybrané pohyby trident snake robota v prostredí MATLAB.This bachelor thesis deals with the description of algorithm for motion planning of trident snake robot. His model is created by means of differential geometry. The controllability of the robot is provided by Lie algebra, generated by elementary vector fields and their Lie bracket. The system is approximated by nilpotent approximation. In this thesis is proposed and described algorithm of motion planning with piecewise constant input. This algorithm is further derived for trident snake robot. Finally, selected motions of trident snake robot are simulated and portrayed in enviroment called MATLAB.

Optimization of Snake-like Robot Locomotion Using GA: Serpenoid Design

This work investigates the locomotion efficiency of snake-like robots through evolutionary optimization using the simulation framework PhysX (NVIDIA). The Genetic Algorithm (GA) is used to find the optimal forward head serpentine gait parameters, and the snake speed is taken into consideration in the optimization. A fitness function covering robot speed is based on a complex physics simulation in PhysX. A general serpenoid form is applied to each joint. Optimal gait parameters are calculated for a virtual model in a simulation environment. The fitness function evaluation uses the Simulation In the Loop (SIL) technique, where the virtual model is an approximation of a real snake-like robot. Experiments were performed using an 8-link snake robot with a given mass and a different body friction. The aim of the optimization was speed and length of the trace

SUAS: A Novel Soft Underwater Artificial Skin with Capacitive Transducers and Hyperelastic Membrane

The paper presents physical modeling, design, simulations, and experimentation on a novel Soft Underwater Artificial Skin (SUAS) used as tactile sensor. The SUAS functions as an electrostatic capacitive sensor, and it is composed of a hyperelastic membrane used as external cover and oil inside it used to compensate the marine pressure. Simulation has been performed studying and modeling the behavior of the external interface of the SUAS in contact with external concentrated loads in marine environment. Experiments on the external and internal components of the SUAS have been done using two different conductive layers in oil. A first prototype has been realized using a 3D printer. The results of the paper underline how the soft materials permit better adhesion of the conductive layer to the transducers of the SUAS obtaining higher capacitance. The results here presented confirmed the first hypotheses presented in a last work and opened new ways in the large-scale underwater tactile sensor design and development. The investigations are performed in collaboration with a national Italian project named MARIS, regarding the possible extension to the underwater field of the technologies developed within the European project ROBOSKIN

NASA Tech Briefs, February 1988

Topics covered include: New Product Ideas; NASA TU Services; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Systems; and Life Sciences

CREATING A COHERENT SCORE: THE MUSIC OF SINGLE-PLAYER FANTASY COMPUTER ROLE-PLAYING GAMES

This thesis provides a comprehensive exploration into the music of the ludic genre (Hourigan, 2005) known as a Computer Role-Playing Game (CRPG) and its two main sub-divisions: Japanese and Western Role-Playing Games (JRPGs & WRPGs). It focuses on the narrative category known as genre fiction, concentrating on fantasy fiction (Turco, 1999) and seeks to address one overall question: How do fantasy CRPG composers incorporate the variety of musical material needed to create a coherent score across the JRPG and WRPG divide? Seven main chapters form the thesis text. Chapter One provides an introduction to the thesis, detailing the research contributions in addition to outlining a variety of key terms that must be understood to continue with the rest of the text. A database accompanying this thesis showcases the vast range of CRPGs available; a literature review tackles relevant existing materials. Chapters Two and Three seek to provide the first canonical history of soundtracks used in CRPGs by dissecting typical narrative structures for games so as to provide context to their musical scores. Through analysis of existing game composer interviews, cultural influences are revealed. Chapters Four and Five mirror one another with detailed discussion respectively regarding JRPG and WRPG music including the influence that anime and Hollywood cinema have had upon them. In Chapter Six, the use of CRPG music outside of video games is explored, particularly the popularity of JRPG soundtracks in the concert hall. Chapter Seven concludes the thesis, summarising research contributions achieved and areas for future work. Throughout these chapters, the core task is to explain how the two primary sub-genres of CRPGs parted ways and why the music used to accompany these games differs so drastically

Astronautics and aeronautics, 1977: A chronology

This publication is a chronology of events during the year 1977 in the fields of aeronautical and space research, development, activity, and policy. It includes appendixes, an index, and illustrations. Chronological entries list sources for further inquiry