Prikaz slobodnog prostora za dvonožne hodajuće robote

Motion planning for biped walking robots is a highly demanding task because of the complex kinematics of such machines and the many degrees of freedom involved. One approach to dealing with this problem is to determine a feasible path in a reduced configuration space of the robot and then to perform the motion planning by searching for an appropriate sequence of steps which allows the locomotion along this path. In this work, a novel method for creating a free space representation for biped walking robots is presented. The method rests upon the approximation of the robot by a set of 3D hulls whose shapes allow efficient determination of feasible paths in a 3D configuration space, involving stepping over obstacles and changing the walking level. The robot’s environment is partitioned into two regions. In the first region, 2D motion planning can be performed, while the complexity of 3D motion planning in the second region can be significantly reduced by considering only a restricted set of paths sufficient for solving a wide range of locomotion tasks.Planiranje kretanja dvonožnih hodajućih robota predstavlja iznimno zahtjevan zadatak zbog složenosti kinematike takvih strojeva i velikog broja stupnjeva slobode gibanja. Jedan pristup tom problemu je da se prvo pronađe izvediva staza u reduciranom konfiguracijskom prostoru robota te da se zatim traži odgovarajući niz koraka koji omogućuje kretanje tom stazom. U ovom radu predstavljena je nova metoda stvaranja prikaza slobodnog prostora za dvonožne hodajuće robote. Metoda se temelji na aproksimaciji robota skupom jednostavnih trodimenzionalnih geometrijskih tijela čiji oblici omogućuju učinkovito određivanje izvedivih staza u 3D konfiguracijskom prostoru, koje mogu uključivati prekoračivanje prepreka te prelazak između hodnih površina različitih visina. Okolina robota dijeli se na dva područja. U prvom području može se primijeniti 2D planiranje koraka, dok se složenost 3D planiranja koraka u drugom području može značajno smanjiti tako što se pri planiranju uzima u obzir samo jedan reducirani skup staza, koji je pak dostatan za rješavanje velikog broja praktičnih zadataka

Prikaz slobodnog prostora za dvonožne hodajuće robote

Motion planning for biped walking robots is a highly demanding task because of the complex kinematics of such machines and the many degrees of freedom involved. One approach to dealing with this problem is to determine a feasible path in a reduced configuration space of the robot and then to perform the motion planning by searching for an appropriate sequence of steps which allows the locomotion along this path. In this work, a novel method for creating a free space representation for biped walking robots is presented. The method rests upon the approximation of the robot by a set of 3D hulls whose shapes allow efficient determination of feasible paths in a 3D configuration space, involving stepping over obstacles and changing the walking level. The robot’s environment is partitioned into two regions. In the first region, 2D motion planning can be performed, while the complexity of 3D motion planning in the second region can be significantly reduced by considering only a restricted set of paths sufficient for solving a wide range of locomotion tasks.Planiranje kretanja dvonožnih hodajućih robota predstavlja iznimno zahtjevan zadatak zbog složenosti kinematike takvih strojeva i velikog broja stupnjeva slobode gibanja. Jedan pristup tom problemu je da se prvo pronađe izvediva staza u reduciranom konfiguracijskom prostoru robota te da se zatim traži odgovarajući niz koraka koji omogućuje kretanje tom stazom. U ovom radu predstavljena je nova metoda stvaranja prikaza slobodnog prostora za dvonožne hodajuće robote. Metoda se temelji na aproksimaciji robota skupom jednostavnih trodimenzionalnih geometrijskih tijela čiji oblici omogućuju učinkovito određivanje izvedivih staza u 3D konfiguracijskom prostoru, koje mogu uključivati prekoračivanje prepreka te prelazak između hodnih površina različitih visina. Okolina robota dijeli se na dva područja. U prvom području može se primijeniti 2D planiranje koraka, dok se složenost 3D planiranja koraka u drugom području može značajno smanjiti tako što se pri planiranju uzima u obzir samo jedan reducirani skup staza, koji je pak dostatan za rješavanje velikog broja praktičnih zadataka

Contemporary Robotics

This book book is a collection of 18 chapters written by internationally recognized experts and well-known professionals of the field. Chapters contribute to diverse facets of contemporary robotics and autonomous systems. The volume is organized in four thematic parts according to the main subjects, regarding the recent advances in the contemporary robotics. The first thematic topics of the book are devoted to the theoretical issues. This includes development of algorithms for automatic trajectory generation using redudancy resolution scheme, intelligent algorithms for robotic grasping, modelling approach for reactive mode handling of flexible manufacturing and design of an advanced controller for robot manipulators. The second part of the book deals with different aspects of robot calibration and sensing. This includes a geometric and treshold calibration of a multiple robotic line-vision system, robot-based inline 2D/3D quality monitoring using picture-giving and laser triangulation, and a study on prospective polymer composite materials for flexible tactile sensors. The third part addresses issues of mobile robots and multi-agent systems, including SLAM of mobile robots based on fusion of odometry and visual data, configuration of a localization system by a team of mobile robots, development of generic real-time motion controller for differential mobile robots, control of fuel cells of mobile robots, modelling of omni-directional wheeled-based robots, building of hunter- hybrid tracking environment, as well as design of a cooperative control in distributed population-based multi-agent approach. The fourth part presents recent approaches and results in humanoid and bioinspirative robotics. It deals with design of adaptive control of anthropomorphic biped gait, building of dynamic-based simulation for humanoid robot walking, building controller for perceptual motor control dynamics of humans and biomimetic approach to control mechatronic structure using smart materials

A Stability-Estimator to Unify Humanoid Locomotion: Walking, Stair-Climbing and Ladder-Climbing

The field of Humanoid robotics research has often struggled to find a unique niche that is not better served by other forms of robot. Unlike more traditional industrials robots with a specific purpose, a humanoid robot is not necessarily optimized for any particular task, due to the complexity and balance issues of being bipedal. However, the versatility of a humanoid robot may be ideal for applications such as search and rescue. Disaster sites with chemical, biological, or radiation contamination mean that human rescue workers may face untenable risk. Using a humanoid robot in these dangerous circumstances could make emergency response faster and save human lives. Despite the many successes of existing mobile robots in search and rescue, stair and ladder climbing remains a challenging task due to their form. To execute ladder climbing motions effectively, a humanoid robot requires a reliable estimate of stability. Traditional methods such as Zero Moment Point are not applicable to vertical climbing, and do not account for force limits imposed on end-effectors. This dissertation implements a simple contact wrench space method using a linear combination of contact wrenches. Experiments in simulation showed ZMP equivalence on flat ground. Furthermore, the estimator was able to predict stability with four point contact on a vertical ladder. Finally, an extension of the presented method is proposed based on these findings to address the limitations of the linear combination.Ph.D., Mechanical Engineering and Mechanics -- Drexel University, 201

Bio-Inspired Robotics

Modern robotic technologies have enabled robots to operate in a variety of unstructured and dynamically-changing environments, in addition to traditional structured environments. Robots have, thus, become an important element in our everyday lives. One key approach to develop such intelligent and autonomous robots is to draw inspiration from biological systems. Biological structure, mechanisms, and underlying principles have the potential to provide new ideas to support the improvement of conventional robotic designs and control. Such biological principles usually originate from animal or even plant models, for robots, which can sense, think, walk, swim, crawl, jump or even fly. Thus, it is believed that these bio-inspired methods are becoming increasingly important in the face of complex applications. Bio-inspired robotics is leading to the study of innovative structures and computing with sensory–motor coordination and learning to achieve intelligence, flexibility, stability, and adaptation for emergent robotic applications, such as manipulation, learning, and control. This Special Issue invites original papers of innovative ideas and concepts, new discoveries and improvements, and novel applications and business models relevant to the selected topics of ``Bio-Inspired Robotics''. Bio-Inspired Robotics is a broad topic and an ongoing expanding field. This Special Issue collates 30 papers that address some of the important challenges and opportunities in this broad and expanding field

Sensing and Control for Robust Grasping with Simple Hardware

Robots can move, see, and navigate in the real world outside carefully structured factories, but they cannot yet grasp and manipulate objects without human intervention. Two key barriers are the complexity of current approaches, which require complicated hardware or precise perception to function effectively, and the challenge of understanding system performance in a tractable manner given the wide range of factors that impact successful grasping. This thesis presents sensors and simple control algorithms that relax the requirements on robot hardware, and a framework to understand the capabilities and limitations of grasping systems.Engineering and Applied Science

Mobile Robots Navigation

Mobile robots navigation includes different interrelated activities: (i) perception, as obtaining and interpreting sensory information; (ii) exploration, as the strategy that guides the robot to select the next direction to go; (iii) mapping, involving the construction of a spatial representation by using the sensory information perceived; (iv) localization, as the strategy to estimate the robot position within the spatial map; (v) path planning, as the strategy to find a path towards a goal location being optimal or not; and (vi) path execution, where motor actions are determined and adapted to environmental changes. The book addresses those activities by integrating results from the research work of several authors all over the world. Research cases are documented in 32 chapters organized within 7 categories next described

Affective Computing

This book provides an overview of state of the art research in Affective Computing. It presents new ideas, original results and practical experiences in this increasingly important research field. The book consists of 23 chapters categorized into four sections. Since one of the most important means of human communication is facial expression, the first section of this book (Chapters 1 to 7) presents a research on synthesis and recognition of facial expressions. Given that we not only use the face but also body movements to express ourselves, in the second section (Chapters 8 to 11) we present a research on perception and generation of emotional expressions by using full-body motions. The third section of the book (Chapters 12 to 16) presents computational models on emotion, as well as findings from neuroscience research. In the last section of the book (Chapters 17 to 22) we present applications related to affective computing

Dynamic state estimation for mobile robots

The scientific goal of this thesis is to tackle different approaches for effective state estimation and modelling of relevant problems in the context of mobile robots. The starting point of this dissertation is the concept of probabilistic robotics, an emerging paradigm that combines state-of-the-art methods with the classic probabilistic theory, developing stochastic frameworks for understanding the uncertain nature of the interaction between a robot and its environment. This allows introducing relevant concepts which are the foundation of the localisation system implemented on the main experimental platform used on this dissertation. An accurate estimation of the position of a robot with respect to a fixed frame is fundamental for building navigation systems that can work in dynamic unstructured environments. This development also allows introducing additional contributions related with global localisation, dynamic obstacle avoidance, path planning and position tracking problems. Kinematics on generalised manipulators are characterised for dealing with complex nonlinear systems. Nonlinear formulations are needed to properly model these systems, which are not always suitable for real-time realisation, lacking analytic formulations in most cases. In this context, this thesis tackles the serial-parallel dual kinematic problem with a novel approach, demonstrating state-of-the-art accuracy and real-time performance. With a spatial decomposition method, the forward kinematics problem on parallel robots and the inverse kinematics problem on serial manipulators is solved modelling the nonlinear behaviour of the pose space using Support Vector Machines. The results are validated on different topologies with the analytic solution for such manipulators, which demonstrates the applicability of the proposed method. Modelling and control of complex dynamical systems is another relevant field with applications on mobile robots. Nonlinear techniques are usually applied to tackle problems like feature or object tracking. However, some nonlinear integer techniques applied for tasks like position tracking in mobile robots with complex dynamics have limited success when modelling such systems. Fractional calculus has demonstrated to be suitable to model complex processes like viscoelasticity or super diffusion. These tools, that take advantage of the generalization of the derivative and integral operators to a fractional order, have been applied to model and control different topics related with robotics in recent years with remarkable success. With the proposal of a fractional-order PI controller, a suitable controller design method is presented to solve the position tracking problem. This is applied to control the distance of a self-driving car with respect to an objective, which can also be applied to other tracking applications like following a navigation path. Furthermore, this thesis introduces a novel fractional-order hyperchaotic system, stabilised with a full-pseudo-state-feedback controller and a located feedback method. This theoretical contribution of a chaotic system is introduced hoping to be useful in this context. Chaos theory has recently started to be applied to study manipulators, biped robots and autonomous navigation, achieving new and promising results, highlighting the uncertain and chaotic nature which also has been found on robots. All together, this thesis is devoted to different problems related with dynamic state estimation for mobile robots, proposing specific contributions related with modelling and control of complex nonlinear systems. These findings are presented in the context of a self-driving electric car, Verdino, jointly developed in collaboration with the Robotics Group of Universidad de La Laguna (GRULL)