One of the methods known to stabilize a passive dynamic walk is to restrict a hip joint angle. This effects as resetting the walking dynamics every time at the beginning of the walk. A Constraining Foot Shape is known to give the same effect by a more compact configuration. However, it was not clear how much this dynamics resetting effect will be given for a specific design parameter such as a length of the foot. This paper shows a numerical approach for mis. Firstly, we show a dynamics of walking by 2D stick model with foot length. This is realized by considering a support point exchange effect. Secondly, we show a simulation results by this model. From mis, we show that a longer foot will give a more strong effect of resetting walking dynamics. Finally, we demonstrate the validity of this model by making an actual hardware of 2D stick model with foot length. In this model, a scaffolding effect was avoided by using landing islands on a slope.

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In this paper, the stability of the rimless wheel with the telescopic legs (RW) and the compass-like biped robot (CBR) with the telescopic legs is investigated. The locomotion of RW and CBR is generated by controlling the telescopic legs and hip joint angle. The linearized equations of motion of RW and CBR are approximately rewritten as the linear time-varying system, and the transition equations of RW and CBR are derived. The effects of the control parameters on the stability of RW and CBR are investigated. It is found from numerical results that locomotion of RW and CBR becomes stable as extention and contraction distance and settling time of the telescopic legs increase.

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In this paper, we discuss the possibility and properties of passive bipedal walking on a slippery downhill. First, we develop 4-DOF equations of motion and collision for the passive biped robot that contacts with the ground incorporating sliding friction. We reproduce the sliding frictional force acting on the contact point as the Coulomb friction. Second, we show that a stable walking gait can be generated with suitable initial condition and physical parameters through numerical simulations. Furthermore, we discuss the validity of the instantaneous stance-leg exchange through analysis of the collision dynamics.

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The level walking of the passive walker that is realized only by a waist assist is high transfer efficiency very much. We studied the walking assist device based on human-assisted passive walking. In this paper, we introduce the legged assist walker harmonized with human and demonstrate its effects.

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The aim of this study is to realize the experiment of biped running, and we focus on the bouncing rod dynamics and its mechanism. The key point of bouncing rod dynamics is to transfer horizontal velocity into lifting momentum. In this study, we try to reduce assist force In order to realize it, we attach leg-swing accelerator.We observe diversified it phenomenon.Finally, we make the basis of full independence running in future.

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The aim of this study is to understand the walking mechanism. We particularly focus on the stabilization mechanism of 3D motion. We experimentally demonstrated that 3D motion of rimless wheel is stable. It is important to understand a stabilization mechanism of the rimless wheel by model analysis. In this paper, we construct a model of 3D rimless wheel, and show a simulation result.

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The aim of this study is to understand the mechanism of human walking. We particularly focus on the stabilization mechanism of 3D walking motion. We demonstrated that a simple model of human walking is 3D rimless wheel. In this paper, detailed experimental results of 3D rimless wheel are reported.

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In this study, a passive joint mechanism is attached to the hand of each manipulator to prevent the generation of the internal forces during cooperative transportation by multiple mobile manipulators. The mechanism enables cooperative transportation by position control. However the loads for each manipulator changes according to the grasping pose by the characteristics of the mechanism. In this paper, first, we propose a method of transportation considering the characteristics of the mechanism. Then, we verify the effectiveness of the proposed method by experiments.

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When multiple robots cooperate within same environment, collision avoidance is essential technology for each robot. In order to achieve effective collision avoidance, it is desired to recognize surrounding robot's motion each other. For this purpose, it is appropriate to exchange motion information by inter-robot communication. In this paper, we propose a local communication system for collision avoidance based on inter-robot communication. By rotating a transmitter and a receiver using a motor, spatially seamless communication toward every direction of robot's surroundings is achieved, and spatial resolution of transmission information which changes according to transmitting direction is also improved. We introduce wireless power supply system to rotary transmitter and receiver. Finally, we conducted experiments to confirm performance of the wireless power supply system and communication quality of the local communication system.

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In this research, connective type swarm robots are developed for motion on irregular ground and narrow space in the disaster area and searching tasks. This robot system satisfies two conflicting properties - large body size for overcoming irregular ground and small body size for entering narrow space, by its connection and separation function. Moreover, this system can adapt to the trouble of its unit of swarm, separating its troubled unit and connecting to new one. In this presentation, the concept of connective swarm robot is proposed and basic movement on irregular ground and narrow area of this robot system is simulated and evaluated using 3DCG.

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This paper deals with a monitoring robot system which gives a visual assistance to the operator for tele-operation task. Objective visual information from other viewpoint including the work robot and peripheral environment is important in order to reduce the burden on the operator. In tele-operation task, viewpoint to minimize the ambiguity of region of interesting (ROI) is important. The visual information from this viewpoint is effective in reducing ambiguity space, such as extravisual space and occluded space. In order to capture an effective scene that gives a proper overview for tele-operation task, we introduce method for calculating the spatial entropy and selecting viewpoint based on spatial entropy.

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We propose a method of allocating multiple tasks among heterogeneous robots. The method is based on the theory of comparative advantage which is an economic theory. In this theory, an optimal allocation which is on the Pareto front is given. As an example, we apply this theory to a tidying task and a exploring task performed by two types of robots. In our experiments, we show that both tasks are finished earlier on condition that the allocation is on the Pareto front in the theory of comparative advantage, compared with the case where the allocation is not.

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In this paper, on-line collision avoidance of n-robot industrial manipulators considering whole body has been addressed. AH robots are controlled using unpredictable PTP commands. We have improved the collision map method to be able to detect any potential collisions between all links of the robots. Furthermore, the map has been used skillfully to avoid the collisions by means of time scheduling of command execution times, and to avoid deadlocks which may occur if any robot blocks the movement of the others.

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In our lives, there are a lot of situations in which we need to comer the targets. For example, we need to corner the targets in security, shepherding or sports. The purpose of our research is cornering the target by robots in a finite plane. The task is similar to that of pursuit-evasion games. In pursuit-evasion game, the purpose of pursuers is catching evaders. In many researches, they define touching evaders as catching evaders. However, in real situations, the pursuer cannot catch the evader by touching it. Therefore, in our research, we focus on the area that evaders reach faster than pursuers, and the task is that pursuers decrease the evader's area without crash. To accomplish this task, we combine Voronoi diagrams method and artificial potential method to corner the targets in the finite plane. In addition, we conduct simulation experiments with some participants to show the effectiveness of our algorithm.

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The hearing sense on a mobile robot is important because it requires low calculation cost than camera image and laser-range-finder. However, it is difficult to estimate location of robot using only its hearing sense in noisy indoor environment. In this paper we present acoustic conditions, which robot can follow, of a sound following robot using an array of 2 microphones under multiple sound source. According to the experiment saying Signal (leading robot sound)-to-Noise ratio and noise source direction, the robot can correctly the direction of leading robot estimate in a range of 2 to 2.5 meters with SNR of 6 dB.

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Some complex and diverse behaviors of robot can be represented by hybrid dynamical system which contains both continuous and discrete dynamics. This paper proposes a method that generates motion based on a framework to carry out tasks of cooperative pushing by multiple robots using mode-transition under a framework of the hybrid dynamical system. In particular,we divide the pushing behavior into two modes, "non-contact mode" and "contact mode". We set the motion of robot to move a position where the robot can press the object as "non-contact mode" and the motion of robot to push the object till goal as "contact mode". We generate an appropriate behavior of multiple robots in simulation and demonstrate the effectiveness of the proposed method.]

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We propose a new transfer mechanism for the depalletizing automation of logistics site. We developed a primary prototype of the transfer mechanism which is composed of four linear drive mechanisms, a transfer belt conveyer and a vacuum gripping device with elastic passive joint. Our experiments confirmed that the primary prototype can transfer a cardboard box in 20 degrees rotational shift.

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This study treats the defect detection of the gear parts with image processing. The gear was put on the turn table and its side part was lightened by the LED light equipped on the USB camera. The obtained image was converted to the binalization one. Here, we focused on the fact that the reflection points appeared at the top of the gear. When the gear was rotated on the turn table, the black and white oblong domains on the banalization image were alternately appeared due to the relation between the gear convex-concave shapes. It was divided into three domains to find the reflection points. As a result, it became easy to find the edge line of the gear because the reflected points were always located at the extension of the edge line.

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In this research, the way to support to design automated production line by making a correlation between human working and robot's based on analyzing of human motion was developed. It was seen assembling works as the combination of simple motions of work. The motion of work was became segmented by measuring acceleration and angular speed data and acknowledging motions of simple works and transient states them by using Support Vector Machine(SVM).The working within segmented motions was extracted by using Self-Organizing Maps (SOM) and made correlation between human workings and robot's functions. By the medium of them, the basis of the system to derive robot's features for automated production line was developed.

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Recently, a lot of industrial robots are used in factories. But in spite of spread of industrial robots, finishing robots are not widely used. Because, force control robots are very difficult to set a parameter for pressing workpiece to tool with appropriate force. Moreover, it is necessary to set various parameters according to a process condition. And every time when the new polishing operation is executed, it is necessary to set new parameters. In this study, we aim to achieve the automatic setting system of the task parameter for polishing operation by robot arm. When robot arm executes the polishing operation, influential parameters are press power, grain size of grind stone and hardness of work. Therefore, to realize the automatic setting system of the task parameters, we considered relation between each parameter and final surface roughness.

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Due to introducing robots to industrial production lines, it is expected that the productivity is increased, labor costs are reduced, and regular production is kept. At present, however, dexterity embedded into the robots is much inferior to skills of human beings. To improve the dexterity, we investigate robotic assembly of fixtures used in the production lines. To assemble the fixtures, we use a 4-finger 12 d.o.f. hand with a camera on the palm. In this paper, we investigate a grasp and insertion task of a bolt to a hole. And we investigate a grasp and insertion task of a slide unit to another slide unit. In these tasks, uncertainty of grasping by the hand occurs. To overcome the problem, we utilize the information of a 6-axis force sensor equipped in the robot wrist and the camera image.

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This paper presents a practical usefulness of a proposed method which realizes precise motion control of a SCARA robot by the integration of PWM signals and visual information. In our previous work, a precise reaching task of an end-effector of a SCARA robot was accomplished. In this paper, Pick-and place tasks are demonstrated by the method as an example for more practical. The task is performed by a SCARA robot which has 4 DOFs.

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This paper proposes a novel robotic hand that can grasp objects of various shapes used for assembly tasks. The proposed hand uses granular jamming combined with a multiple finger mechanism. Due to the effect of granular jamming, the pose of a grasped object does not change during an assembly operation. The proposed hand has four fingers where two are active ones and the other two are passive ones. We use the passive fingers to orient an object placed on a table before the active fingers are closed to grasp it. The active fingers can adapt to the shape of an object due to its underactuated mechanism. Experimental results on assembly of two kind of parts are shown to validate the effectiveness of our proposed hand.

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A basic procedure to tune force-based control of peg-in-hole assembly was developed based on the parameter effect analysis using dynamics simulations. With respect to each stage of the generalized programming process that was distilled from the observations of professional engineers' demonstrations, relations between performance indices and control parameters were investigated and organized into a parameter-tuning procedure. The resultant procedure's utility was tested with a real robot system.

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NC (Numerical Control) machine tools is the device which automated operation of a machine tools by numerical control, and it is contributing to rationalization of production at a factory and so on. Machine operation of the NC machine tools is automated, but a human operator needs to determine a processing parameters. An inappropriate parameter causes high loading state operation or cause any problems. In this paper, force sensor-less cutting resistance detection using observers on NC machine tools.

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