This paper deals with control of crane tele-operation system considering power assisted conveyance. We design a new crane tele-operation system using zero phase notch filter and model predictive control. We apply the zero phase notch filter to power assist controller in master enviroment and apply the model predictive control to feedback controller in slave enviroment respectively. The zero phase notch filter enables to modify frequency characteristics of operating torque without signal distortion on the line in oder to suppress vibration of the load-rope of crane. The model predictive control enables to suppress vibration of the load-rope of crane sufficently in comparison with conventional system. Some results of simulation and experiment are given in order to verify the usefulness of our proposed system.
This paper proposes a multi-joint-gripper that achieves envelope grasping for unknown shape objects. Proposed mechanism called Driving Mechanism (DM) is based on a chain of Planetary Gear Systems (PGS) controlled by only one motor. It also has a Variable Stiffness Mechanism (VSM) that controls joint stiffness to relieve interfering effects suffered from grasping environment. The experiments elucidate that the developed gripper achieves envelop grasping; the posture of the gripper automatically fits the shape of the object with no sensory feedback. And they also show that the VSM effectively works to relieve external interfering. This paper shows the detail of the mechanism and the experiments of its motion.
Animal collective behaviours are regarded as emergent properties that result from local interaction between individuals in a swarm. Then we discern between individual movements and swarm behaviour. Dynamic swarm, however, might manage both of them in parallel. Swarm of soldier crabs seemed to change individual behavioural rules in water-crossing behaviours. We conducted experiments where the regular oscillations by soldier crabs resulted from collective movements triggered by cohesion. Then we focus on effects from a collective to individuals and vice versa. We demonstrate bidirectional characteristics that swarm of soldier crabs have.
For the lane departure warning system or the lane keeping system, it is important to detect lane lines stably in images from vehicle onboard cameras. We have developed the lane line detection system for platooning. This system can detect various kinds of lane markings stably and robustly because it uses a multi-information map containing road marking information, such as a kind of road marking, the width of a lane line or degree of blur, to detect lane markings. A multi-information map is tied to position data obtained from GPS system. Therefore, a vehicle can obtain information about lane markings to detect at the present position from a multi-information map. This paper proposes the method to construct a multi-information map automatically by recognizing road markings in images from an onboard front camera. Input images are transformed to inverse perspective projection images. In these transformed images, seven features are extracted to discriminate road markings. Experiments conducted in real road scenes show the effectiveness of the proposed method for constructing a multi-information map.
In most study of collective behavior, many numerical models have been developed. However, there is little field data collected for comparison with the models. We observed soldier crabs in Iriomote Island, Japan, which live in tideland forming big swarms, and analyzed their collective motion by transforming their positions on two-dimensional coordinates. The results of analysis show that the fluctuation of their motion positively contributes to maintenance and/or formation of a swarm, in contrast to the fluctuation of classical model, which is given as just random noise.
This paper proposes a new reinforcement learning approach for acquiring conflict avoidance behaviors in multi-agent systems. Multi-agent systems are able to establish orderly systems autonomously through interaction with autonomous agents. We expect to be able to construct flexible and robust systems for the environmental changes by using multi-agent system approaches. However, it is difficult for designers to preliminarily embed appropriate behaviors to avoid conflict because complex dynamics emerges by interaction between many agents. We apply the proposed method to the narrow road problem that many agents go by each other in a narrow road, and verify the effectivity of the proposed method. In the narrow road problem, it is the optimal strategy that an agent selects going forward and another agent selects giving way. However, it is difficult for agents to decide which strategy to select because they cannot predict other agents' behaviors beforehand. The proposed method can differentiate into agents preferring to go forward and agents preferring to give way, by using Q-learning that can adjust discount rates. We solve conflict problems in multi-agent systems through autonomous functional differentiation of many learning agents. Through experimental results, we showed that agents differentiated into two type of agents, and acquired stable conflict avoidance behaviors with high probability than a conventional Q-learning.
Our objective is to understand behavioral versatility of animals from the perspective of well-coordinated rhythmic and non-rhythmic movements. To this end, we focus on an ophiuroid as a simple good model living organism that exhibits self-organized role assignment of rhythmic and non-rhythmic arm movements in locomotion. Although we have reproduced such versatile arm movements by using an active rotator model that can describe both oscillatory and excitatory properties, coordination of movements has been achieved in a specifically limited situation. In order to overcome this issue, we reexamine the model so that the role assignment of arm movements is realized in more general situations. Simulation results show that the ophiuroid omnidirectional locomotion in response to an attractant or repellent stimulus is successfully realized by using the proposed model.
We performed label-free detection of β-lactoglobulin and compared sensitivity of metallic mesh sensors with different size of periodic structure. Since transmission property of the metallic mesh is affected by refractive index around openings, application for a refractive index sensor has also been studied. In this work, 3 types of metallic meshes (estimated resonance frequency at 3, 10 and 40THz) were prepared and β-lactoglobulin was fixed on the surface of the metallic mesh. We succeeded to acquire transmission property of metallic meshes performed in mid-infrared using 7-µm grid constant and 50 times higher sensitivity than 3THz mesh (76-µm grid constant). The result suggests small scale of periodic structure is advantageous for applications such as trace detection of protein reaction.
A power assist glove supporting the finger motions has been developed. Its control based on a human intention is desired. Then EMG is introduced to measure the human intention. In the proposed method, EMG signals are used to discriminate the finger motions from the wrist motions. In this paper, the discriminating method using EMG and neural network is proposed, and then the effectiveness of proposed one is experimentally verified.
In the stock-raising industry, it is known that beef fat quality is related to texture and scent. However, in meat markets, there is currently no method of directly evaluating fat quality on-line. Using near-infrared imaging, we have developed new equipment for evaluating the fat quality in beef rib eye. It consists of three selected, spectral wavelength LEDs and a near-infrared camera. In order to test the accuracy of this equipment, a series of prediction tests were carried out using 33 independent samples in the meat market. According to the cross-validation, the standard margin of error for the estimated accuracy of oleic acid was 2.34%. These results showed that this equipment is a rapid and non-destructive method for visualizing and evaluating the distribution of oleic acid in stock at meat markets.
RT Middleware is useful as a framework for a robot's productivity drive. However, in advancing spread and promotion, subjects occur. They are the difficulty of introduction of technological know-hows of RT Middleware, and the little of those who can develop corresponding software. Then, we thought that we would enable it to treat RT Middleware on the Android framework who has spread widely all over the world quickly. Therefore, we developed “RTM on Android”, a RT-Middleware for the Android platform. By using our “RTM on Android”, you are able to develop application-RT-Components for Android easily, now.
This paper describes a method for automated THA planning incorporating joint functionalities. The optimal planning is formulated as maximum a posterior (MAP) estimation, which ensures the best-balance of joint functionalities and bone-implant spatial relations based on their statistical models derived from the training datasets prepared by an experienced surgeon. According to the performance evaluation, two of the three functionalities were significantly improved by incorporating the statistical model of the functionalities when compared with the previous method and all of the average values of joint functionalities were higher than the surgeon's plans. Implant Size error in 33 cases out of 37 cases were within one size. We consider these results showed a potential usefulness of the proposed method. Future work will include the clinical validation of the method and a full automation of preoperative planning.
It is necessary for the patient who met with a traffic accident to perform echography immediately. We have developed the tele-echography device which the doctor who is in the hospital during transportation can inspect by remote control. In this paper, we report new attachment mechanisms of the device. Conventional system has an attachment mechanism with a corset. This mechanism has to pass a corset through between patient's body and ground. It is hard to attach this device to patient used by this method. Furthermore patient suffers damage by moving their body. We developed, therefore, new mechanisms which we can put it on the front of the body and evaluated their installability and robustness in a vehicle.
This paper describes a development of a robot cart platform for intelligent personal mobility. Recently, a lot of personal mobility has been used by aged and handicapped people. Intelligent mobility provides safer and more convenient transfer service such as driving support and automatic transfer. It is necessary to develop a platform equipped with sensors and electronic devices intelligent navigation functions. In this paper, we describe the hardware components and the software configuration of the robot platform. The navigation system, including the functions of localization using grid map matching, path following, and obstacle avoidance, is implemented on the proposed robot platform. We also present the results of an open-field experiment in Tsukuba Challenge 2011 and evaluate the proposed systems.
When we teach motions to conventional industrial robot arms by Hand-Guiding instruction, the bad manipulability of the robot arms sometimes prevents us from teaching motions to them. In this paper, we apply the robot dual shell to an industrial robot arm. The robot dual shell has no contact with the robot arm. And the robot arm tracks the motion of the robot dual shell. Therefore introducing the robot dual shell improves the manipulability of the robot arm and maintains the range of movement of the robot arm. As a result, we can teach motions to the robot arm by Hand-Guiding instruction. Through the quantitative evaluation of manipulability and the practical operation, we show that the robot dual shell structure is indeed effective in improving manipulability.
We are developing a mobile robot system which searches targeted industrial tools and clears up them in the laboratory room. First, this robot moves to the front of tool board and checks the tools which are not returned, and registers them as the clearing targets. Then, this robot runs round in the room and searches them from desks, to bring them back to the board. There are many technological subjects to realize such a robot. In these subjects, searching targeted tools are essential one. In this paper, we propose a method for searching targeted tools by image processing. And, we show implementation of the prototype robot and experimental results of searching targeted tools in the laboratory room.
The objective of this research is autonomous path following control for head-feeding combine robot, especially improvement of turning control. An RTK-GPS and a GPS compass are used as navigation sensor. The combine robot obtains its position and heading angle information from them to go straight and turn along target path. Kalman filter estimates lateral and heading angle errors from data of position, heading and traveling speed for steering control. In the experiment, the combine robot followed spiral path harvesting rice. And then, lateral error, heading angle error and the size of space required for the turn control were evaluated. The rms lateral error was observed to be less than 0.06m and the rms heading angle error was less than 2.35 degree in the straight path. The average lateral and heading error in the turning control were 0.13m and -2.49 degree, respectively. The size of space required for the turn control was 4.4m×4.5m. It is almost equivalent to the operation by human.
In this paper, we show that ankle elasticity of biped robots improves energy-efficiency of walking. One of major issues in studies of humanoid robots is the realization of energy-efficient walking. To realize biped robots achieving energy-efficient walking, researchers have studied flat-footed biped robots with mechanical impedance at each ankle from a viewpoint of biomechanics. Although they achieved energy-efficient robotic walking using the ankle elasticity, they have not clearly shown that the effects of the ankle elasticity improve the walking performance yet. To analyze the effects of the ankle elasticity, we first show an equivalence between walking of flat-footed biped robots with ankle impedance and that of arc-footed biped robots using Extended-Roll-Over-Shape (EROS). We then discuss effects of the ankle elasticity from the viewpoint of this equivalence.
Recently, autonomous robots have been actively developed in manufacturing due to orbital space-free and personnel reduction for production line. Especially, in the plants treating a liquid such as foods, chemicals and molten metal, the liquid transferring robots with an open container are used. However, in the case of the packaging for liquid medicine products and transferring molten metal, liquid containers are transferred slowly to prevent outflow and intervention of air or gas. Thus, transfer motion spends a lot of time and delays tact time. Therefore, in this paper, the sloshing suppression control in open liquid container transfer system is proposed. In many previous sloshing control researches, mathematical models of pendulum type that can be estimated firstmode sloshing are mainly built. These models can express the behavior of liquid at the side-wall of a container. Although these approach can suppress the sloshing, the liquid surface is tilted by the effect of inertia while a liquid container is accelerated with high-speed. Therefore, in this research, the sloshing suppression control method with transferring and tilt motion is proposed. This paper proposes to completely suppress sloshing (liquid vibration) by both of transfer and tilt control using Generalized Predictive Control (GPC).
This research aims to develop a mobile system with long-thinned cord-like structure for searching and inspection tasks in confined deep space. The system is designed to provide certain mobility capability, localization ability, and flexibility in system composition to adapt to the searching environments. A simple new Active Joint Mechanism is introduced to meet long-thinned cord-like requirements, with its complete kinematic analysis provided. Active- and passive-segmentalization and hybrid train structure for the system are proposed to enable the adjustment of mobility capability, internal sensor based localization ability, and variable-length composition of the system. A realization on a prototype system with a multimodal searching sensor mounted, communication networks for motion control and sensor information embedded, and user interface provided, is presented.
This paper proposes a method to construct a three-dimensional (3D) model of an outdoor scene containing a large amount of information by combining local stereo images which are acquired from multiway. It is difficult to reconstruct outdoor scenes accurately using a single view of a stereo camera because the distance to a target is very far compared with the stereo camera's baseline length. Therefore the proposed method makes the 3D model accurately by reducing the uncertainties of a 3D point from various angles to the region which includes the correct point. Multi-view stereo images are captured using a rotational stereo camera that swings back and forth and can capture not only the upper surface of an object but also the side surface of the object. As an experiment, a blimp robot with a rotational stereo camera is used to capture aerial stereo images of the ground. The proposed method achieves the dense and accurate reconstruction of the outdoor 3D model.
We propose a motion curve optimization method based on a genetic algorithm. A motion curve is a function of displacement of a drive part of a machine with respect to time. In a curve optimization using a standard genetic algorithm, an optimized curve is searched by repeatedly applying genetic operations to design variables that define the shape of motion curves. In contrast, the algorithm we proposed directly treats curves as solutions without design variables, and we also propose genetic operations for motion curves. These are methods that can generate a new curve by numerically synthesizing several curves; even more complex curves could be created by applying the operations repeatedly. The effectiveness of the proposed algorithm is demonstrated through optimization of a motion curve to decrease vibration at the surface of a liquid in bottles for a bottling machine.
The purpose of this study is to develop a wearable master-slave upper limb training device, which can be used to a passive training for a trainee who cannot move by oneself. Developed device has 7 D.O.F by using three kinds of pneumatic artificial muscles, which are chosen as suitable actuators to move each human joint. In this paper, cooperated movements are experimented to verify a capability of slave device. It is confirmed from the result that a subject who uses the slave device can follow the trainer movement. Therefore, this device may be possible to train all upper limb joints independently and cooperatively.
To realize a non-invasive hands-free interface for use in daily life, we propose a head-motion interface using an air pillow. This air pillow consists of four air bags in a layered overlapping pattern whose air pressures are measured to control the cursor's position as well as click and drag operations on a PC screen. In accordance with the initial condition of the pillow and the user's head movement ability, rapid and user-friendly cursor manipulation is implemented. Based on the throughput and click time performance indices, a comparison is made with an existing interface to evaluate the proposed method as a practical hands-free interface.
Recently, robotics systems are focused to assist in Single Port Endoscopic Surgery (SPS). However, the existing system required a manual operation of vision and viewpoint, hindering the surgical task. We proposed a surgical endoscopic robot for SPS with dynamic vision control, the endoscopic view being manipulated by a master controller. The prototype robot consists of a manipulator for vision control, and dual tool tissue manipulators (gripping: 5DOFs, cautery: 3DOFs) can be attached at the tip of sheath manipulator. Feasibility of the robot was demonstrated in vitro experiment. The “cut and vision control” is suitable for precise cutting tasks in risky areas while a “cut by vision control” is effective for rapid macro cutting of tissues. A restriction task was accomplished using a combination of both methods. Moreover, this paper addresses an in vivo experiment. We showed that vision control in the stomach and a cautery task by a cautery tool could be effectively achieved.
Researches on co-creation systems and that on internal measurement share some basic views on complex systems. These are the researches on features of complex systems which include some duality such as explicit/implicit information or global/local interaction, etc. For experiments and analyses based on the views, we need a theoretical framework describing the duality. In this study, two types of interaction are introduced. One is “explicit interaction” which is defined by conventional usage of functions, and the other is “implicit interaction” which is defined by a generalized determination process of function parameters. These interactions are formalized via duality on vector spaces and generalized inverse matrices. Implicit interaction is defined by the form which is similar to statistical parameter estimation but is not the same. It derives a Cauchy distribution on parameter fluctuation and structural branch on parameters.
Cells are the main component of our structures and functions, but the effective methods to examine the viability and activity of cultured cells in a non-invasive and unlabeled measurement haven't been fully developed. In this study, we demonstrated a completely new cell measuring technique based on an attenuated total reflection (ATR) spectroscopy in terahertz (THz) region, which is emerging with promising biological science. The cultured cell showed lower absorption than the medium between 1 and 13THz, and the decrease of the cell viability indicates a good correlation to the ATR signal.