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Dynamical colony pattern formation in motile cyanobacteria Pseudanabaena sp. was investigated. Collectives of the bodies are self-organized and form various motile colony patterns on agar plates. The coexistence of collective movements of four types was observed: translationally moving single strands, bundles, comet-like colonies, and a rotating disk. Additionally, the colony patterns switch to others...
In this study, changes in the pulse direction and flight path of bats during an obstacle-avoiding flight were experimentally investigated. While flying in unfamiliar space, bats often produced pairs of emissions (double pulses) and shifted the pulse direction between immediate obstacles and their intended flight direction. To confirm the practical effectiveness of the bats' behaviour, the observed...
The purpose of the research is to develop a myriapod robot i-CentiPot ??? that achieves significant mobility against unpredictable environment via passive dynamics. In the paper, we change foot phase, and observe locomotion. We also consider about the analogy between i-CentiPot ??? and some myriapoda.
The plasmodium of the true slime mold, physarum polycephalum is a large amoeboid organism, and it can sense environmental information and change its behavior depending on the situations. For example, when the expanding front touches the wall, other part will start to move and become a new front in a few minutes. It seems physarum transmits information from one side to another. This property must be...
The coordination of body and limbs motions contributes to effective propulsion in limed locomotion. However, there is lack of understanding that characterizes the mechanism underlying the body-limb coordination. The aim of this study involves clarifying the mechanism through mathematical modeling and dynamic simulation. To this end, a body-limb coordination model was designed based on a simple rule...
The ant Ondontomuchus kuroiwae has a trap jaw that snaps quickly to capture a prey. The ant opens the trap jaw, locks it and closes quickly if it detects a prey using a sensory hair on the jaw. We here analyze 3-dimensional structure of the trap jaw muscles by using a micro volume imaging with an X-ray micro-computed tomography (micro-CT) to elucidate the mechanism of the exoskeletal muscular system...
This paper discusses numerical experiments by the fast computation method of hydraulic robot dynamics. This paper shows a new proposed model with a special nondmensional representation which is based on the proposed model. The four methods are compared with each other with respect to computation time.
Unlike the conventional gravity compensations, this paper provides simpler gravity compensations based on a Casimir function. First, we propose an impedance control approach by which the gravity is compensated. Second, we propose a force control approach by which the gravity is compensated. Finally, the effectiveness of both approaches is confirmed by numerical simulations.
The drones are used for many purposes such as structure inspections, pesticide sprayings, photographys, load carriages and investigations in the world. The drones have a week point that it is difficult to fly them in the strong wind. However, it is an important task to fly in the strong wind for the disaster relieves. In this paper, we show the modeling and the attitude control system design of a...
Typically, crop-sprayers are designed to be used at the farmland located far from residence. However, farmlands may be found often in the middle of residence. Crop-sprayer for such dotted farmland should be designed specifically not to distribute chemicals outside of the farmland. The purpose of this research is to figure out the optimum configuration for spraying chemicals for dotted farmland.
This paper proposes a visual servo control design for a wheeled mobile robot. This control is for a passing system between a moving object. The controller detects the passable space based on optical flow, and a reference marker on image plane generates automatically by using the optical flow. The mobile robot goes through between a moving object, e.g., a transport robot in a factory. The system is...
In this paper, we improve a running speed of a biped robot by using a control law of a new wobbling mass. In the model of the biped robot, the running speed decreases when using a conventional control law of the wobbling mass. We first describe the conventional running control law of the biped robot and propose a control law that moves the wobbling mass up and down so that the forward direction component...
In this paper, we propose an optimization model for planning a robust path against changes in traffic volume. Robustness is based on the form of the travel time function. The proposed model can be applied not only when traffic volume increases but also when it decreases. In addition, the proposed model can set the ratio of consideration by a parameter depending on whether the traffic volume is increasing...
This study investigates the effects on optimal merging trajectories due to the trade-off between fuel consumption and terminal time. The merging optimization method that simultaneously optimizes arrival trajectories and the sequence of aircraft has the potential to improve future decision support systems for air traffic control. In previous work, the merging optimization method minimized only the...
This paper present a tabu search based method for train crew scheduling. Methods for generating an initial train crew schedule and neighborhood schedules are developed in this paper. The proposed method is applied to a simple train timetable. The results indicate that the proposed method can generate an appropriate schedule for the applied train timetable.
This paper addresses the vibration control problem of a nuclear refueling machine (RM) that transports fuel rods to given reactor locations in water. First, Hamilton's principle is used in developing a hybrid lumped-mass and distributed-parameter model of the RM to investigate the underwater vibrations of the fuel rods caused by the RM's movements. In deriving the control law, the hydrodynamic force...
This paper presents a proportional integral-proportional derivative (PI-PD) control with feedforward compensation for positioning control of a magnetic levitation (maglev) system. Maglev system has gained numerous attention in high speed and precision engineering applications. However, it remains a challenging task to obtain a satisfactory positioning performance for the maglev system due to its inherently...
In this paper, we propose a robust steering pinion angle control of Column mounted Electric Power Steering (C-EPS) for autonomous vehicle lateral control. An augmented observer was utilized for a rejection of external disturbances such as road reaction torque. By considering C-EPS mechanical structure, a reduced C-EPS dynamic model is utilized when constructing proposed controller. Also, the stability...
Simulation of the traffic flow is an effective approach to resolve the traffic congestion problem and expect to elucidate the traffic congestion mechanism. In this paper, we propose a traffic flow model based on the MLD (Mixed Logical Dynamical) system approach which regard the lane change and overtaking behavior. The research revealed that traffic jam spreads from driving lane to overtake lane.
A driver assistance control algorithm for a vehicle with an active front steering system is proposed in this paper. The control algorithm is designed so as to optimize the turning performance and realize the collision avoidance simultaneously under the constraints on the front wheel turn angle and the lateral tire force. The control algorithm is developed based on a model predictive control law for...
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