Query: Mayuko Iwamoto

title: Decentralised control of multiple mobile agents for quick, smooth, and safe movement
abstract: There are growing applications of multiagent systems in which each mobile agent moves towards its destination while avoiding others, e.g. robots in warehouses, self driving cars, and flying drones. In these systems, it is desirable that each agent moves quickly, smoothly, and safely. However, simple methods for satisfying these three functions simultaneously have not been developed. To address this challenge, we capture the essential control mechanism for achieving multiobjective tasks, drawing inspiration from pedestrian flow. We propose a decentralised control scheme, an extension of the social force model, which is a simple model of pedestrian flow, wherein agents can avoid other agents based on the prediction of their future motions. Through simulations, we demonstrate that the proposed control scheme enables agents to move quickly, smoothly, and safely.

title: Decentralized Control for Self driving Cars That can Freely Move on Two dimensional Plane
abstract: In the current traffic rules, cars have to move along lanes and to stop at red traffic lights. However, in the future when all cars become completely driverless, these traffic rules may vanish and cars may be allowed to move freely on two dimensional plane by avoiding others like pedestrian flow. This innovation could greatly reduce traffic jams. In this study, we propose a decentralized control scheme for future self driving cars that can freely move on two dimensional plane, based on the social force model widely used as the model of pedestrian flow. The performance of the proposed scheme is validated via simulation. Although this study is still conceptual and does not consider realistic details, we believe that it paves the way to developing novel traffic systems.

title: Basis of self organized proportion regulation resulting from local contacts.
abstract: One of the fundamental problems in biology concerns the method by which a cluster of organisms can regulate the proportion of individuals that perform various roles or modes as if each individual is aware of the overall situation without a leader. In various species, a specific ratio exists at multiple levels, from the process of cell differentiation in multicellular organisms to the situation of social dilemma in a group of human beings. This study determines a common basis for regulating collective behavior that is realized by a series of local contacts between individuals. In this theory, the most essential behavior of individuals is to change their internal mode by sharing information when in contact with others. Our numerical simulations regulate the proportion of population in two kinds of modes. Furthermore, using theoretical analysis and numerical calculations, we show that asymmetric properties in local contacts are essential for adaptive regulation in response to global information such as group size and overall density. Particle systems are crucial in allowing flexible regulation in no leader groups, and the critical condition that eliminates overlap with other individuals (the excluded volume effect) also affects the resulting proportion at high densities. The foremost advantage of this strategy is that no global information is required for each individual, and minimal mode switching can regulate the overall proportion. This simple mechanism indicates that proportion regulation in well organized groups in nature can be realized through and limited to local contacts, and has the potential to explain various phenomena in which microscopic individual behavior results in orderly macroscopic behavior.

title: Decentralized Control Scheme That Well integrates Peristaltic Movement with Friction Control

title: The advantage of mucus for adhesive locomotion in gastropods.
abstract: For many gastropods, locomotion is driven by a succession of periodic muscular waves (contractions and relaxations) moving along the foot. The force generated by these waves is coupled to the substratum by a thin layer of pedal mucus. Gastropod pedal mucus has unusual physical properties: the mucus is a viscoelastic solid at small deformation and shows a sharp yield point; then, at greater strains, the mucus is a viscous liquid, although it will recover its solidity if allowed to heal for a certain period. In this paper, to clarify the role of the mucus and the flexible muscular waves in adhesive locomotion, we use a simple mathematical model to verify that directional migration can be realized through the interaction between the periodic muscular waves and the specific physical features of mucus. Our results indicate that the hysteresis property of mucus is essential in controlling kinetic friction for the realization of crawling locomotion. Furthermore, our numerical calculations show that both the hysteresis property of mucus and the contraction ratio of muscle give rise to two styles of locomotion, direct waves and retrograde waves, which until now have been explained by different mechanisms. The biomechanical effectiveness of mucus in adhesive locomotion is also discussed.

title: Hand shape recognition using the sEMG of the upper extremity
abstract: In this paper, we propose a hand shape recognition method using the sEMG (surface electromyography) of the upper extremity. The upper extremity sEMG is acquired using Myo which is a wearable device. The target hand shapes are three: Rock, Paper, and Scissors. For hand shape recognition, four features obtained with FFT and wavelet transform are used. SVM and an improved k NN are used for classifiers. For hand shape recognition, the proposed method performs ensemble learning using these features and the classifiers. The ensemble learning to be used is AdaBoost.M1. As a result of the experiment, the recognition rate of Rock, Paper and Scissors are 86% 81.3% and 75.6% respectively.

title: Mechanism of spiral formation in heterogeneous discretized excitable media.
abstract: Spiral waves on excitable media strongly influence the functions of living systems in both a positive and negative way. The spiral formation mechanism has thus been one of the major themes in the field of reaction diffusion systems. Although the widely believed origin of spiral waves is the interaction of traveling waves, the heterogeneity of an excitable medium has recently been suggested as a probable cause. We suggest one possible origin of spiral waves using a Belousov Zhabotinsky reaction and a discretized FitzHugh Nagumo model. The heterogeneity of the reaction field is shown to stochastically generate unidirectional sites, which can induce spiral waves. Furthermore, we found that the spiral wave vanished with only a small reduction in the excitability of the reaction field. These results reveal a gentle approach for controlling the appearance of a spiral wave on an excitable medium.

title: Effects of an Obstacle Position for Pedestrian Evacuation: SF Model Approach
abstract: In order to study pedestrian dynamics, mathematical models play an important role. It is well known that a social force model exhibits clogging or what is called the "faster is slower effect" (Helbing et al.  2000) Also, the authors in Frank and Dorso ( 2011) and Kirchner et al. ( 2003) reported that an obstacle facilitates and obstructs evacuation of pedestrians trying to get out of a room with an exit, dependently on its position, size, and shape. In particular, as stated in Frank and Dorso ( 2011) an obstacle has a strong influence on pedestrians if it is put in a site shifted a little from the front of the exit. However, it has not been shown where and how it is the most efficiency to set up an obstacle. Thus we investigate the dynamics of pedestrians and clarify the effect of a disk shaped obstacle with various sizes placed in several positions via numerical simulations for a social force model. Finally, we calculate a leaving time of pedestrians for each size and position of an obstacle, and determine an "optimal size" of an obstacle in the case that it is set up in a site shifted from the front of the exit.

title: Basis of self organized regulation resulting from local communications

title: Collective Intelligence Self organized Regulation Resulting from Local Interactions