The paper describes development of prototype of the novel sensor node with impact resistance capability for gathering disaster area information. We have been discussing the development of the gathering information system for disaster area by utilizing rescue robots and wireless sensor networks. Then we propose launching deployment method of the sensor node for deploying dangerous place where a human and robot cannot enter. In order to realize launching deployment, the sensor node has to be protected from dropping impact. Therefore, we covered the sensor node by impact-resistance structure. Prototype of the sensor node consists of plastic ball for the impact-resistance structure and the sensor node core for sensing, communication and information processing. Experiment confirmed that prototype of the sensor node was able to communicate and launch.
When multiple robots perform a cooperative task that a single robot cannot solve with its capabilities, such as transportation or monitoring, the robot system achieves efficient operation by controlling a robot swarm with the density that is suitable for the task. For instance, the robot swarm requires high- and low-density structures for transporting heavy objects and monitoring a large area, respectively. Thus far, researchers have studied lattice-structure-based collective movement with regular organizations and amorphous-structure-based flocking behavior with irregular organizations. However, both control methods use a high-density swarm or aim for that state. In this study, we propose distance and angular potentials to control the filling density of robots based on regular tessellations and a collective movement method to maintain the latticed structure constructed by these potentials. This study demonstrates the collective movement of the robot swarm with lattice structures with different densities and quantitatively evaluates the structural changes caused by the movement.
Users of smartphones and/or tablet terminals browse and download confidential document files routinely. Therefore, a higher security level is needed for smartphones and tablet terminals than conventional mobile phones. From this kind of background, Takahashi and Uchida proposed an image-based user authentication method for touch screen devices by using the latest image shot by the user as the pass-image. The proposed authentication method is resistant to smudge attacks, one of the most serious threats for touch screen devices. However, the security strength of the method is low. Therefore, in this paper, we propose SWIPASS, an image-based user authentication method for touch screen devices that has higher security strength, by improving on the method proposed by Takahashi and Uchida. This improves the security strength without any change in either the resistance to smudge attacks or the users' burden of memorizing. Although Takahashi and Uchida implemented their method only as a prototype system in their study, we implement SWIPASS as a real Android application in this study. Moreover, we also examined the usability and the resistance of SWIPASS against observation attacks by conducting several experiments in this paper.
This article discusses functions of a stationary underwater sensor node (S-USN) with attached algae removal ability for constructing underwater monitoring sensor network (UMSN) that is used to support coral ecological system survey activities. The experiments of attached algae growth was conducted in Okinawa coast. Based on knowledge obtained by the experiments and coral researcher's advice, container surface wiping function was implemented to S-USN.
Swarm robotic systems control multiple robots in a coordinated manner for using this flexible coordination to solve complex tasks in various environments. Such systems can utilize the individual capabilities of robots scattered within the swarm as well as the collective capabilities of the assembled robots. By coordinating these capabilities, swarms can solve tasks with a range of purposes, including carrying out rough sweeps of the overall environment using scattered robots or detailed observation of a part of the environment using assembled robots. This study developed a self-organization method for constructing regular groups of robots from scattered robots to achieve coor-dination between individual and collective states. An approach that integrates elements of self-organization with different input information requires centralized control to manage them. To provide this self-organization without centralized control, we focus on using the phase-field method and cellular automata to facilitate crystal growth that produces ordered structures from scattered particles. We formulate a method for arranging robots in a self-organizing manner based on the geometrical regularities of tile-able lattices (honeycomb, square, and hexagonal lattices) on a two-dimensional plane, demonstrate the process undertaken in carrying out the proposed method, and quantitatively evaluate the effectiveness of the lattice-based geometrical regularity approach. The proposed method contributes to carrying out tasks with a range of purposes by organizing states with either individual or collective capabilities of robot groups.
This paper describes a model of passer's kick behavior considering cooperative pass play for a RoboCup middle size soccer player agent. In the RoboCup middle size league, realization of advanced cooperative pass play with improvement of players' autonomy is expected. However, such advanced pass play couldn't be seen yet in a present RoboCup game. Generally, it is necessary to control a landing position of kicked ball by a passer for an effective pass in soccer game. Therefore, a kick behavior of passer was modeled to realize advanced cooperative pass play in this paper. A passer's behavior was modeled based on mechanical features of a kick device installed on a player robot. Experimental results showed that a ball can be controlled for pass to an arbitrary position by using a proposed model.
In this paper, we describe a position determination method using the Reinforcement Learning in the RoboCup soccer. In the RoboCup Soccer, one of the aims is a realization of cooperative action among multiple robots. In previous studies, a localization algorithm in dominant area has been proposed. However, it is difficult that multiple robots behave adaptively using existing methods in a dynamic environment like the RoboCup Soccer. In order to solve the maladjustment of such an environment, we propose a method for position learning method using the dlaunay triangulation and the reinforcement learning,. The proposed method is applied to the RoboCup soccor simulation and usefulness of the method is confirmed.
In the Middle Size Robot League (MSL) of RoboCup Soccer, many studies have been discussing about various approaches for realizing cooperative play. However, they are mainly discussing offensive behaviors such as a pass, a dribble and a shoot action, and then it is not including defensive behavior. Hence, we have been discussing cooperative defensive behavior for RoboCup Soccer. In order to achieve proposal system, we have developed and implemented DELAY behavior to our RoboCup MSL team "The_Nishikey" as the first step. DELAY is a part of action of cooperative defensive behavior of the robot. DELAY is a defensive behavior which keeps distance with the enemy carrying ball constant, and intercepts continuous cooperative play such as the pass and the shoot to delay the enemy action. This paper describes a development of DELAY. Through an experiment, we confirmed that DELAY was available for cooperative defensive behavior.
Purpose The purpose of this paper is to propose a novel wireless sensor node (SN), with impact resistant capability, for launch deployment into closed areas. In disaster areas, gathering disaster area information is crucially important to prevent secondary disasters. However, gathering information is usually associated with the risk of death and/or accident for rescue workers in closed areas. The authors propose the SN for gathering information in dangerous places, inaccessible to rescue workers and robots, by utilizing launch deployment. Design/methodology/approach Buffer material is essential when designing an impact‐resistant structure. The authors adopted the air cushion as general buffer material when considering the directional characteristics of sensor mounting and wireless communication quality and developed the expression for determining the thickness of the air cushion using the parameters of SN size, mass, air pressure and acceleration. The authors developed a sensor node with impact resistant structure by utilizing the proposed determination method of air cushion thickness. Findings In the evaluation of impact resistant structure in free fall, launch deployment, the authors verified that the impact resistant structure protected the SN, and the performance of configured devices on the SN. Then, the authors examined the effect of the impact‐resistant structure on wireless communication between SNs. The structure had no effect on electric field intensity, throughput, or packet jitter, which confirmed that the wireless communication capacity was unaffected by the structure. Originality/value In this paper, a new design method is stated for a sensor node with an impact‐resistant structure by utilizing an air cushion as a general buffer material.
