In this research, we have developed a robot called D-PaDY, to work in cooperation with workers in the automobile door assembly line. In this paper, we specifically describe the concept and the design of the Door Gripper. The Door Gripper is a component of the D-PaDY, which automatically grasps a car door. By using the Door Gripper, the D-PaDY cooperates with the worker in the process of assembling the door into the vehicle body, allowing to reduce assembly time and improve the efficiency of the process.
The endoskeleton humanoid robot needs an artificial muscle that is comparable with a human muscle from a viewpoint of form, flexibility, output force, output displacement and the responses. For this realizing, we are studying a Shape Memory Alloy (SMA) actuator that protected by a rolled film tube have the high heat resistance and the high flexibility. In this study, this actuator is inserted into a natural rubber tube for mobilizing and experimented about its antagonistic stiffness control.
Short-circuit faults in windings due to the deterioration of insulation is one of the most common faults in motor drive systems. An easy and effective fault diagnosis method is urgently required to ensure a highly reliable operation. The magnetic field in the stator of motor is found to change after the occurrence of the short-circuit fault and it is clear that a change of magnetic field is affected by the frequency of voltage applied to the winding. In this paper, based on this phenomenon, a new identifying system which diagnose a stator slot in which a short-circuit fault has occurred is developed. In this paper, firstly, a new means of identifying a stator slot with a short-circuit fault is explained. Secondly, in order to realize the method as an identifying system, the prototype system is developed. Finally, by using this identifying system, magnetic flux density of each slot directly above are measured, the effectiveness of the system is evaluated.
Sensory disturbance is a very common following stroke, and severe sensory loss may inhibit the ability of patients to use the affected upper limb in daily activities, even when they have good motor function. We hypothesized that task-specific training with sensory feedback may improve patients' ability to manipulate objects. We developed a system of sensory feedback using transcutaneous electrical nerve stimulation (SENS) for stroke rehabilitation and investigated its effectiveness. In this study, we conducted a case studies with stroke patients. The instability of tip pressure during a cube pinch and lifting task was improved after one hour's training with SENS, although it was not changed by training without SENS. We concluded that SENS would be useful in the rehabilitation of stroke patients with sensory loss.
This paper describes a method for detection of change of enviornmental conditions using analysis of series of wireless LAN signals. The method uses the charcteristics that the signal strength of the wireless LAN changes according to the conditions of the indoor environment such as the number of persons surroundings of the wireless LAN access points and clients. The paper discusses the method for validating the change of the conditions using the measurement of the indoor environment using the imaging devices and the change detection result of the series of the signal strength of wireless LAN system using singular spectrum transformation. We show the feasibility of the proposed method through the system integration and experimental results.
Recently, the importance of 3D interaction is increasing. We realize immersive 3D environment based on eyeware-free 3D image and high-speed hand gesture interface. For the aerial image, we use a display technology called AIRR and the 3D high-speed handtracking and gesture recognition make it possible to manipulate the aerial image in high-speed. The system we integrated is called “AIRR Tablet” which recognizes hands or any other objects in high-speed beyond human perception. We achieved immersive input and output having a small delay. We can perform operations without any physical contact (Drag&Drop, Punch, Drawing, and Pinching).
High-speed vision technology in which not just image capturing and recording but also image processing are executed simultaneously at high frame rates, exceeding video rates (30Hz), has recently been considered an important technology for various applications, such as robotics, and man-machine interfaces. However, the image processing performed in conventional high-speed vision systems is mainly based on two-dimensional pattern recognition. In order to extend the possibilities of this technology, here we focus on real-time three-dimensional sensing at the speeds achievable by high-speed vision systems. Although a related approach for high-speed 3D sensing can achieve a frame rate of over 200 fps, there are disadvantages, including the need for multiple captured frames during sensing, a limited measurement range and low resolution. Our proposed real-time 3D sensing system consists of a projector and two cameras. By projecting a well-designed segmented pattern and using three-viewpoint epipolar constraints, the proposed system can obtain 3D points at high speed. The developed system robustly obtained a 3D shape at 500fps in real time.
This paper describes the extraction method of low up and down steps and objects in urban area. For autonomous mobile robots, one of the most important technologies is a travelable area extraction. It is similar to extract the low obstacles. However, the position of the laser scanner is unstable since the most of road surface is rough. Therefore, low objects are often confused with the ground and it is difficult to distinguish them by measurement of height. On the other hand, the horizontal distance measured by the 3D-laser scanner has a difference. The measurement distance to the low object is shorter than ground. The distance table as reference is adopted. The scan data from a 3D-laser scanner is compared with the table to extract the low object. On the experiments in outdoor environment, the curb stones of the load under 10cm were extracted correctly in several scene. This method contributes navigation scene that a robot avoids contact with most of the objects in urban area.
This paper propose a novel deployment method of Wireless Mesh Network (WMN) using a group of mobile robots equipped with a wireless transceiver. Our proposed method utilize rough relative positions of the robots estimated by Radio Signal Strength Indicators (RSSI) to deploy WMN. Our algorithm is consist of following two parts; (1) Fully distributed and dynamic role decision method among robots and (2) Adaptive direction control using time difference of RSSI. In this research, we evaluate performance of proposed and conventional methods which use RSSI at simulated disaster area including radio-wave propagation and wireless communication protocol models. As a result of simulations and real robots experiments, our proposed method outperformed conventional methods in aspects of required deployment time and traveled distance of the robots.
This paper proposes a design of RTC (Robotics Technology Component specified by OMG) for MIDI (Musical Instrument Digital Interface), which is a standard interface for electronic musical instruments. It is also useful for entertainment robots, as well as electric musical instruments, that play a musical instrument. In face, MIDI is often used for music playing robots to enable them to cooperate with other robots and musical instruments, so it is useful to provide the interface to MIDI on common robotics frameworks. This paper describes how to handle MIDI on RTM (Robotics Technology Middleware). First, the structure of a MIDI RTC is proposed, and then, based on it, basic MIDI RTCs are implemented. These RTCs are verified by constructing a simple music system that controls a MIDI keyboard and a software synthesizer. Next, a practical music playing robot system that plays the handbells is implemented based on our proposal. The robot gave musical performances of handbells to several audiences. Through questionnaire to the audience, the effectiveness of the proposed framework is verified.
Coherence of a network means that it is made up of functions of nodes glued together. In our previous work [Haruna, T., 2013. BioSystems 114, 125-148], we showed that coherence of directed networks can be captured by the lateral path which is dual to the usual directed path. In this paper, we study coherence along lateral paths emerging from random Boolean network dynamics. A stochastic way to walk on a directed network along lateral paths based on sensitivity of random Boolean dynamics is proposed and coherence percolation is introduced. We develop mean-field and semi-mean-field theories for coherence percolation and derive the critical condition. As an application to real-world networks, we show that coherence percolation on the gene regulatory network of a bacterium Escherichia coli can be well-captured by the semi-mean-field theory. For the bacterium gene regulatory network, the coherence criticality precedes the dynamical criticality. We discuss the relationship between coherence of the network and the degree distribution in terms of the dynamical criticality hypothesis of real-world gene regulatory networks.
To establish an estimation method of beef marbling score in live beef cattle, we have investigated correlations among bioelectrical impedance properties in the sirloin part, the content of crude fat in the ribulose part and the sirloin part, and the Beef Marbling Standard (BMS) number. The measurement was conducted with 42 beef cattle one month before slaughter treatment. We adopted the four-electrode method robustly to measure the bioelectrical impedance properties. The needle electrodes were inserted into the four points: 100, 125, 225, 250 [mm] in a line from the last lumbar vertebra. The extracellular resistance Rex, the intracellular resistance Rin, and the cellular membrane capacitance Cm were calculated using the measured data. As the result, a significant correlation was found between Rin, and BMS number. The results suggest that the Bioelectrical Impedance Analysis (BIA) can be useful to estimate the BMS number of live fattening cattle.
This paper describes a case study of the thermal and humidity measurement in the agricultural environment. In this case study, we intend to observe a spatial distribution of the thermal and humidity in the cultivation environment. Generally, artificial cultivation methodology, such as a precision agriculture or a smart agriculture, uses an environmental control technology that makes a proper condition for the crop growth. Main objective of this measurement is observing and analyzing an effectiveness of the environmental control precisely. In this paper, we propose a multi-point sensing method and report current results of the case studies in the practical agriculture field.