Wireless systems are being applied in not only consumer area but also industrial automation plants and factories. Industrial automation systems require high reliable and high available communication systems. And, several industrial wireless communication protocols have been developed and published as International Standards. Then industrial wireless communication systems compliant with such standards are provided and applied in many industrial automation plants and factories all over the world. Coexistence in industrial automation application is considered in IEC/SC65C/WG17, and IEC 62657 series has been developed and it is explained. And, actual procedures of wireless coexistence management and how to use templates for coexistence according to IEC 62657-2 are described and application for hydrogen station is considered in this paper.
This paper considers the serving task for the table tennis robot. Based on the physical models, the ball trajectory is formulated where the ball is hit by the racket and rebounds on the table in own court and in the opponent's court. Then the paper clarifies which variables among the ball's position, translational and rotational velocities can be controlled independently by the serving racket. Some numerical simulations verify the results work approximately well.
In this study, we consider a regulation problem for molecular robotics realized by DNA reactions. The control objective is to regulate the concentration of a target DNA strand to a desired level using practical DNA circuits. This is a challenging problem as regards to the architecture of the molecular robot, because of the corresponding positiveness, modularity, and finiteness problems. A DNA comparator-based controller with DNA amplifiers is proposed, and it is shown to successfully achieve the control objective. The properties and the stability of the system are evaluated in terms of both retroactivity and the Lyapunov stability theory for a positive second-order system. To the best of our knowledge, this is the first study to realize a regulator in a practical DNA reaction system for molecular robotics.
The quasi-linear ARX radial basis function network (RBFN) model has shown good approximation ability and usefulness in nonlinear system identification and control. It has an easy-to-use structure, good generalization and strong tolerance to input noise. In this paper, we propose a self-organizing quasi-linear ARX RBFN (QARX-RBFN) model by introducing a self-organizing scheme to the quasi-linear ARX RBFN model. Based on the active firing rate and the mutual information of RBF nodes, the RBF nodes in the quasi-linear ARX RBFN model can be added or removed, so as to automatically optimize the structure of the quasi-linear ARX RBFN model for a given system. This significantly improves the performance of the model. Numerical simulations on both identification and control of nonlinear dynamical system confirm the effectiveness of the proposed self-organizing QARX-RBFN model.
This paper describes optimal decentralized PID control with any controller structure for systems with relative degree no more than 2 from the viewpoint of an inverse linear quadratic problem. We have shown that the decoupling matrix is related to both in optimality and stability of the closed loop system so far. However, a condition for the LQ optimality has never been provided in the case where the inverse of the decoupling matrix does not belong to decentralized controller structure. In this paper, we derive a necessary and sufficient condition for the LQ optimality. Moreover, our approach for decentralized control is improved from block diagonal controller structure into any structure. We then provide concrete methods of optimal and stable decentralized controllers, respectively. Finally, we show that a desired transient response with decoupled input/output characteristics can be achieved by our decentralized controller, and illustrate the effectiveness of our proposed method by simulation.
Map matching, the ability to match a local map built by a mobile robot to previously built maps, is crucial in many robotic mapping, self-localization, and simultaneous localization and mapping (SLAM) applications. In this paper, we propose a solution to the “map-to-text (M2T)” problem, which involves the generation of text descriptions of local map content based on scene understanding to facilitate fast succinct text-based map matching. Unlike previous local feature approaches that trade discriminativity for viewpoint invariance, we develop a holistic view descriptor that is view-dependent and highly discriminative. Our approach is inspired by two independent observations: (1) The behavior of mobile robots given a local map can often be characterized by a unique viewpoint trajectory, and (2) a holistic view descriptor can be highly discriminative if the viewpoint is unique given the local map. Our method consists of three distinct steps: (1) First, an informative local map of the robot's local surroundings is built. (2) Next, a unique viewpoint trajectory is planned in accordance with the given local map. (3) Finally, a synthetic view is described at the designated viewpoint. Because the success of our holistic view descriptor depends on the assumption that the viewpoint is unique given a local map, we also address the issue of viewpoint planning and present a solution that provides similar views for similar local maps. Consequently, we also propose a practical map-matching framework that combines the advantages of the fast succinct bag-of-words technique and the highly discriminative M2T holistic view descriptor. The results of experiments conducted using the publicly available radish dataset verify the efficacy of our proposed approach.
This paper focuses on an asynchronous program evolution in evolutionary computation, which is hard to evolve programs effectively unlike a synchronous program evolution that evolves individuals effectively by selecting good parents after evaluations of all individuals in each generation. To tackle this problem, we explore the mechanism that can promote an asynchronous program evolution by selecting a good individual without waiting for evaluations of all individuals. For this purpose, this paper investigates the effectiveness of the proposed mechanisms in genetic programing (GP) domain by evaluating it in the two types of problems, the arithmetic and the Boolean problems. Through the intensive experiments of the eight kinds of testbeds under the two types of problems, the following implications have been revealed: (1) the program asynchronously evolved with the proposed mechanism can be completed with mostly the same or shorter execution steps than the program asynchronously evolved without the proposed mechanism, in particular the proposed mechanism improves the performance of the asynchronous evolution in the arithmetic problems; and (2) the program asynchronously evolved with the proposed mechanism can be completed with mostly the same or shorter execution steps than the program evolved by the conventional GP.
This paper addresses broadcast control for a group of Markov chains. The problem studied here is to find a controller governing multiple Markov chains by observing the group performance and sending the same signal (corresponding to the transition probability) to all the Markov chains indiscriminatingly. As a solution to the problem, we consider here integral-type broadcast controllers and provide a sufficient condition for the controller gain to stabilize the resulting broadcast control system. The condition enables us to design the gain without the precise information on the system, such as the number of Markov chains. This will be an advantage in dealing with large-scale systems having uncertainty. It is also demonstrated by numerical simulation that the result is useful for constructing broadcast control systems.