Snake Aerial Manipulators: A Review <s> B. DESIGN CONSIDERATIONS OF FLIGHT TO THE WORKING AREA AND TRANSFORMATION SEQUENCE 1) COORDINATION AND PARALLEL PROGRAMMING IN PHYSICALLY RESTRICTED FLIGHT OF MULTIPLE UAVs <s> This paper provides a theoretical framework for analysis of consensus algorithms for multi-agent networked systems with an emphasis on the role of directed information flow, robustness to changes in network topology due to link/node failures, time-delays, and performance guarantees. An overview of basic concepts of information consensus in networks and methods of convergence and performance analysis for the algorithms are provided. Our analysis frame- work is based on tools from matrix theory, algebraic graph theory, and control theory. We discuss the connections between consensus problems in networked dynamic systems and diverse applications including synchronization of coupled oscillators, flocking, formation control, fast consensus in small- world networks, Markov processes and gossip-based algo- rithms, load balancing in networks, rendezvous in space, distributed sensor fusion in sensor networks, and belief propagation. We establish direct connections between spectral and structural properties of complex networks and the speed of information diffusion of consensus algorithms. A brief introduction is provided on networked systems with nonlocal information flow that are considerably faster than distributed systems with lattice-type nearest neighbor interactions. Simu- lation results are presented that demonstrate the role of small- world effects on the speed of consensus algorithms and cooperative control of multivehicle formations. <s> BIB001 </s> Snake Aerial Manipulators: A Review <s> B. DESIGN CONSIDERATIONS OF FLIGHT TO THE WORKING AREA AND TRANSFORMATION SEQUENCE 1) COORDINATION AND PARALLEL PROGRAMMING IN PHYSICALLY RESTRICTED FLIGHT OF MULTIPLE UAVs <s> Cooperative Control of Multi-Agent Systems extends optimal control and adaptive control design methods to multi-agent systems on communication graphs. It develops Riccati design techniques for general linear dynamics for cooperative state feedback design, cooperative observer design, and cooperative dynamic output feedback design. Both continuous-time and discrete-time dynamical multi-agent systems are treated. Optimal cooperative control is introduced and neural adaptive design techniques for multi-agent nonlinear systems with unknown dynamics, which are rarely treated in literature are developed. Results spanning systems with first-, second- and on up to general high-order nonlinear dynamics are presented. Each control methodology proposed is developed by rigorous proofs. All algorithms are justified by simulation examples. The text is self-contained and will serve as an excellent comprehensive source of information for researchers and graduate students working with multi-agent systems. <s> BIB002 </s> Snake Aerial Manipulators: A Review <s> B. DESIGN CONSIDERATIONS OF FLIGHT TO THE WORKING AREA AND TRANSFORMATION SEQUENCE 1) COORDINATION AND PARALLEL PROGRAMMING IN PHYSICALLY RESTRICTED FLIGHT OF MULTIPLE UAVs <s> Team Cooperation in a Network of Multi-Vehicle Unmanned Systems develops a framework for modeling and control of a network of multi-agent unmanned systems in a cooperative manner and with consideration of non-ideal and practical considerations. The main focus of this book is the development of synthesis-based algorithms rather than on conventional analysis-based approaches to the team cooperation, specifically the team consensus problems. The authors provide a set of modified design-based consensus algorithms whose optimality is verified through introduction of performance indices. <s> BIB003 </s> Snake Aerial Manipulators: A Review <s> B. DESIGN CONSIDERATIONS OF FLIGHT TO THE WORKING AREA AND TRANSFORMATION SEQUENCE 1) COORDINATION AND PARALLEL PROGRAMMING IN PHYSICALLY RESTRICTED FLIGHT OF MULTIPLE UAVs <s> Introduction.- Robotic Networks and the Consensus Problem.- The Data Association Problem.- D-RANSAC: Distributed Robot Consensus.- Fast Consensus with Chebyshev Polynomials.- Cooperative Topological Map Building Using Distributed Consensus.- Conclusions. <s> BIB004 </s> Snake Aerial Manipulators: A Review <s> B. DESIGN CONSIDERATIONS OF FLIGHT TO THE WORKING AREA AND TRANSFORMATION SEQUENCE 1) COORDINATION AND PARALLEL PROGRAMMING IN PHYSICALLY RESTRICTED FLIGHT OF MULTIPLE UAVs <s> We propose a novel multi-rotor flying platform, ODAR (omni-directional aerial robot), which is fully-actuated (i.e., can assume arbitrary motion in SE(3) or generate arbitrary control wrench in se(3)) by six opportunistically distributed rotors, each driven by reversible ESC (electronic speed controller) for bi-directional thrust generation. Due to this omni-directional wrench generation, the ODAR system can realize such powerful behaviors impossible with conventional multi-rotor flying platforms as: 360° photo/video shooting while holding its position for VR scene generation; or resisting sideway gust while keeping its attitude and exerting downward pushing force larger than its own weight for aerial manipulation applications. This paper presents optimal mechanical design, modeling and control, hardware and software implementation, and experimental verification of the ability of the ODAR system to attain those behaviors impossible with the conventional drones as stated above. <s> BIB005 </s> Snake Aerial Manipulators: A Review <s> B. DESIGN CONSIDERATIONS OF FLIGHT TO THE WORKING AREA AND TRANSFORMATION SEQUENCE 1) COORDINATION AND PARALLEL PROGRAMMING IN PHYSICALLY RESTRICTED FLIGHT OF MULTIPLE UAVs <s> In this study, we investigated a novel type of the multirotor aerial vehicle with two-dimensional multilinks to demonstrate stable aerial transformation for high mobility in three-dimensional environments. Our goal was to tackle the challenge of traversing narrow spaces or gaps, which is one of the difficulties for existing structure of multirotors, especially in the cluttered indoor environment of disaster sites. The research involved three steps. First, we developed the modeling of the link modules that compose a multirotor with two-dimensional multilinks and conducted a quadrotor prototype. Second, we derived a stable flight control method for aerial transformation on the basis of linear-quadratic-integral optimal control. Third, we investigated the motion planning for the aerial transformation using a state validation method and path optimization in the joint space to maintain the stability during transformation. Successful aerial transformation and the ability of the prototype to negotiate narrow gap... <s> BIB006 </s> Snake Aerial Manipulators: A Review <s> B. DESIGN CONSIDERATIONS OF FLIGHT TO THE WORKING AREA AND TRANSFORMATION SEQUENCE 1) COORDINATION AND PARALLEL PROGRAMMING IN PHYSICALLY RESTRICTED FLIGHT OF MULTIPLE UAVs <s> In this letter, we introduce a novel transformable aerial robot called DRAGON, which is a dual-rotor-embedded multilink robot with the ability of multi-degree-of-freedom (DoF) aerial transformation. The new aerial robot can control the full pose in $\mathsf {SE}(3)$ regarding the center of gravity (CoG) of multilinks and can render the multi-DoF aerial transformation, which is accomplished by the original two-DoF force vectoring mechanism on each link called the dual-rotor gimbal module. The dynamics is derived on the basis of the special definition of CoG orientation, followed by a control method decoupled into thrust force control and rotor gimbal control. In the thrust force control, the minimum force norm is considered to avoid force saturation, and the rotor gimbal control method is developed to enhance both translational and rotational stabilities during hovering and large-scale aerial transformation. The prototype composed of four links is constructed, and associated preliminary experiments are performed. The feasibility of the novel mechanical design and the proposed control method for the aerial transformation is demonstrated. <s> BIB007
This can be centralized if a single processor is used and the system it is viewed not as a set of collaborative UAVs but as a set of propellers with full-body interaction. In this case a novel and complex model of equations is needed and a first approach was recently developed by BIB007 ,  , BIB005 , BIB006 . On the other hand, the flight can be decentralized (multiprocessor) if each UAV uses its respective processor and in this way, the whole system is viewed as a coordinated group of autonomous UAVs. The Pixhawk autopilot is capable of performing both modes of operation with aerial manipulators having up to 8 propellers (i.e 2 quadrotors or either 4 coaxial aircrafts or maybe eight single-copters). The problem of centralized operation is the surcharge of data-processing and control tasks for a single processor unit, and also the modeling and control. The main problem of decentralized control is regarding with coordination and consensus  , BIB002 ,  BIB001 BIB003 BIB004 .