Contributions to the modelling and control of two-wheeled mobile robots

Wheeled mobile robots moving on uneven terrain are attracting interest at an impressive pace. In the work reported here two distinct architectures of two-wheeled mobile robots are proposed.The first architecture, corresponding to the case where the two wheels linked by a frame lie in a vertical plane, constitutes the material of our earlier research and is laid out in the appendix. The system being unilaterally constrained by the environment, slipping or losing contact with the ground can occasionally occur. Therefore, nine distinct topologies are identified and accounted for in the model describing all the possible motion modes of the system. The mathematical model is formulated using the Natural Orthogonal Complement (NOC) and takes into account the terrain geometry. Additionally, the model includes necessary conditions for the switching between the distinct topologies.The second architecture pertains to an Anti-Tilting Outdoor Mobile robot, ATOM, composed of two spherical wheels and a cylindrical central body. The spherical shape of the wheels allows the robot to restore its posture after flipping over, thus giving it the anti-tilting property. Moreover, this particular shape ensures pure-rolling motion on uneven terrain without resorting to any adaptive structure; i.e., without increasing the complexity of the system. Here, also, the mathematical model is developed using the NOC, while taking into account the terrain geometry. Moreover, constraints on the terrain curvatures are derived in order to ensure pure rolling. Although the design of ATOM is simple, this brings about new challenges in terms of control. According to its structure, ATOM pertains to the class of Mobile Wheeled Pendulums (MWP). A feature common to MWPs, that is not encountered in other wheeled robots, is that their central body, which constitutes the platform of the robot, can rotate about the wheel axis. Therefore, aside the nonholonomy aspects encountered in conventional wheeled robots; the central body stabilization problem is pointed out here and rigorously treated in order to avoid unstable zero-dynamics. For that, an intrinsic dynamcal property, referred to as the natural behaviour of the system, is brought forward and employed to control the heading velocity of the robot using the inclination of the central body. Moreover, a particular selection of the generalized coordinates and the system outputs allows a global stabilization of the system without resorting to any linearization. Furthermore, a posture control (preceded by a velocity and orientation control) is proposed based on sliding mode and Lyapunov function for navigation. Finally, the robust aspect of the controller is underlined by showing the control behaviour versus an over/under estimation of system parameters

Climbing and Walking Robots

With the advancement of technology, new exciting approaches enable us to render mobile robotic systems more versatile, robust and cost-efficient. Some researchers combine climbing and walking techniques with a modular approach, a reconfigurable approach, or a swarm approach to realize novel prototypes as flexible mobile robotic platforms featuring all necessary locomotion capabilities. The purpose of this book is to provide an overview of the latest wide-range achievements in climbing and walking robotic technology to researchers, scientists, and engineers throughout the world. Different aspects including control simulation, locomotion realization, methodology, and system integration are presented from the scientific and from the technical point of view. This book consists of two main parts, one dealing with walking robots, the second with climbing robots. The content is also grouped by theoretical research and applicative realization. Every chapter offers a considerable amount of interesting and useful information

Towards understanding of climbing, tip-over prevention and self-righting behaviors in Hexapoda

Die vorliegende Dissertation mit dem Titel “Towards understanding of climbing, tip-over prevention and self-righting behaviors in Hexapoda” untersucht in drei Studien exemplarisch, wie (i) Wüstenameisen ihre Beine einsetzen um An- und Abstiege zu überwinden, wie (ii) Wüsten- und Waldameisen ein Umkippen an steilen Anstiegen vermeiden, und wie sich (iii) Madagaskar-Fauchschaben, Amerikanische Großschaben und Blaberus discoidalis Audinet-Servill, 1839 aus Rückenlagen drehen und aufrichten. Neuartige biomechanischen Beschreibungen umfassen unter anderem: Impuls- und Kraftwirkungen einzelner Ameisenbeine auf den Untergrund beim Bergauf- und Bergabklettern, Kippmomente bei kletternden Ameisen, Energiegebirge-Modelle (energy landscapes) zur Quantifizierung der Körperform für die funktionelle Beschreibung des Umdrehens aus der Rückenlage

Aerial Vehicles

This book contains 35 chapters written by experts in developing techniques for making aerial vehicles more intelligent, more reliable, more flexible in use, and safer in operation.It will also serve as an inspiration for further improvement of the design and application of aeral vehicles. The advanced techniques and research described here may also be applicable to other high-tech areas such as robotics, avionics, vetronics, and space

Climbing and Walking Robots

Nowadays robotics is one of the most dynamic fields of scientific researches. The shift of robotics researches from manufacturing to services applications is clear. During the last decades interest in studying climbing and walking robots has been increased. This increasing interest has been in many areas that most important ones of them are: mechanics, electronics, medical engineering, cybernetics, controls, and computers. Today’s climbing and walking robots are a combination of manipulative, perceptive, communicative, and cognitive abilities and they are capable of performing many tasks in industrial and non- industrial environments. Surveillance, planetary exploration, emergence rescue operations, reconnaissance, petrochemical applications, construction, entertainment, personal services, intervention in severe environments, transportation, medical and etc are some applications from a very diverse application fields of climbing and walking robots. By great progress in this area of robotics it is anticipated that next generation climbing and walking robots will enhance lives and will change the way the human works, thinks and makes decisions. This book presents the state of the art achievments, recent developments, applications and future challenges of climbing and walking robots. These are presented in 24 chapters by authors throughtot the world The book serves as a reference especially for the researchers who are interested in mobile robots. It also is useful for industrial engineers and graduate students in advanced study