This paper reports on the development of a multi-robot cooperation system for human-robot communication. In the system, robots behave as if they are communicating by speech, while the system exchanges information through a network for keeping the timing of the communication natural. The exchanged information through the network is based on analysis of inter-human conversation. This system is based on a scripting language for coordinating multi-robot communication, which has a merit for developer of easy development. The developed system is used for Manzai, which is a Japanese comedy conversation mainly performed by two people. While the tempo and timing are particularly important in Manzai, the developed “robot Manzai” system was more highly evaluated than the Manzai shown in a video performed by humans. We believe that this system demonstrates the potentials of robots as a passive-social medium; like television and computers.

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This paper presents a new scan matching method for mobile robot localization and mapping. The proposed method utilizes Euclidean invariant features in order to match an input scan with a reference scan using no initial alignment. This method is capable of global scan matching in environments having curved objects. Experimental results show that our method successfully performed map building and global scan matching in a large environment (corridor) and a complex-shape environment (room) .

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This paper proposes a KDD (knowledge discovery and data mining) approach to motion control for humanoid robots. The aim of this approach is to discover the knowledge for generating stable motions in balance. In this paper, we propose a motion control system, which can generate a stable and anti-tumble motion by the concept learning and the searching in the motion space: extracting some generalized motion guideposts by decision tree learner and motion generation with tracking the guidepost by hill-climbing search. The motion control system has three parts: training, learning, and generating part. Former two parts are to acquire the balancing property of itself body and movement by decision tree learning for numbers of executed training motions, and latter one part provides the search technique for the motion control based on the acquired knowledge concerning balance and stability in the motion. In this paper, some performance results by humanoid robot HOAP-1 are reported: stable and anti-tumble motions to stand up from a chair. This paper also reports some performance for the change in the environments: standing up from a chair on slope and different in height.

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This paper discusses the mobile robot PMR-5 with the preliminary-announcement and display function which indicates the forthcoming operations to the people near the robot by using a projector. The projector is set on a mobile robot and a 2-dimensional frame is projected on a running surface. In the frame, not only the scheduled course but also the states of operation can be clearly announced as the information about movement. We examine the presentation of the states of operation such as stop or going back including the time information of the scheduled course on the developed robot. Scheduled course is expressed as the arrows considering the intelligibility at sight. Arrow expresses the direction of motion directly and the length of arrow can announce the speed of motion. Operation until 3-second-later is indicated and three arrows classified by color for each second are connected and displayed so these might show the changing of speed during 3-second period. The sign for spot revolution and the characters for stop and going back are also displayed. We exhibited the robot and about 200 visitors did the questionnaire evaluation. The average of 5-stage evaluation is 4.5 points and 3.9 points for the direction of motion and the speed of motion respectively. So we obtained the evaluation that it is intelligible in general.

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In this paper, a remote control mechanism for the crawler-type robot by use of flexible shafts is proposed. Since the robot does not have to mount any power unit for the locomotion on the body, the weight of the robot can be lightened and it can mount other devices alternatively. Furthermore, since the electric power is not used to the mobile mechanism on the body, the danger of fire is extremely low even if it performs rescue operation in collapsed building with gas leakage. To construct the proposed mobile mechanism, we devise the structure of the flexible shafts. We make up an experimental crawler-type robot which is composed of the proposed mechanism. Then the feasibility of the remote control system with the proposed mechanism is demonstrated by several experiments.

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This paper presents design of a new antagonistic variable stiffness hinge using noncircular gears. First, we show a method to convert a torsion spring to an arbitrary nonlinear torsion spring by nonuniform circular motion of noncircular gears. This nonlinear torsion spring is called ρ²-Spring. Next, a pair of ρ²-Springs are connected antagonistically to comprise a variable stiffness joint. Moreover, the design method of ρ²-Spring and β²-Hinge which have arbitrary characteristic is developed. We explain the characteristics of this joint theoretically and evaluate its capability of wide range stiffness. We also present experimental results of the prototype.

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The purpose of this paper is to realize a kind of more natural and efficient walking of a biped robot. In the beginning of paper, we discuss methods of walking based on passive dynamic walking mechanism and naturalness of walking. Next, we introduce some kinds of walking using variable length knees with constraint control of a body. Finally, our biped called Prototype Biped Emu IV (PBEmu-IV) is introduced, some experimented results are shown to verify the effectiveness of our strategy for biped walking, and the frequency analysis is introduced for walking. As the results, walking frequencies only depended on frequencies of knee length variations, and walking is excited around the characteristics frequency of legs. That is to say, some effective frequencies for biped walking are appeared in the sense of high walking gains.

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In this research, toward a realization of Mechanical Speech Synthesizer as a part of a man type utterance robot, we develop a element of the robot. Following a concept of biomimetics, artificial tongue constitutes elements taking finite triangle elements which imitated arrangement of man's Lingual muscle. And each element transforms under the constant volume, becouse some branches of that triangle shrink actively, some the branches become longer passively. These triangular elements are located in the shape of a mesh, and form lingual shape. At first, we consider the mechanism which can transform for a few elements with experiment and simulation.

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Marionette system provides an intuitive teleoperation system for the difficulty controlling whole-body motion of a multi-joint robot and the complicated observation of its condition. This system employs a small robot which has similar form to a control target as an operating/displaying device, so that the device provides an operational feeling like manipulating a doll, so it is named Marionette Device. Since the characteristics of the Marionette device and the target robot are synchronized bilaterally in the system, the operation of Marionette device is reflected intuitively in the target, and the robot motion is also displayed simultaneously by the Marionette device. In this paper, we develop a humanoid type device as Marionette device in order to operate a humanoid robot HRP-2 and implement a whole-body teleoperation method. The remote walking and manipulation experiments in an unknown environment are introduced. In this experiment, the operator should guess the remote environment using a head camera view and control legs and arms by the Marionette device. We propose a new operation method for controlling foot position and leg joints with the Marionette device. It makes possible to walk by pointing a foot stamp step by step in a stable place. To show the effectiveness of the proposed system, we compare another teleoperating system which employs a joystick and a 3DCG display for control and understanding the state of remote robot. The experimental result shows effectiveness of the Marionette system and it has potential of teleoperating humanoid robots with other devices for complementing each other.

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In this paper we realize a real-time communication on Ethernet and develop an onbody distributed I/O system for a humanoid robot, HRP-3P. Real-time communication on Ethernet is realized by (1) a communication method using the data link layer directly and (2) timing control using a real-time operating system ARTLinux. This enables us to reduce the cost of embedded systems and improve developmental efficiency. A CORBA implementation which works on this communication layer is also developed to increase compatibility with existing software. Finally a small-size distributed controller is developed for the onbody network of HRP-3P and a distributed I/O system is developed on top of this.

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In laparoscopic surgery, surgeons can use only rod-shaped instruments that can be inserted through a trocar and therefore high techniques are required. To overcome this problem, much work has been done to develop multi-degree-of-freedom forceps. However they are still inadequate to handle or retract large organs, like a spleen, pancreas, and liver. This paper proposes mechanical hands with detachable fingers that can be assembled in the abdominal cavity, each of whose parts is inserted through a trocar. Two types of such three-fingered hands are developed. The three fingers of one of them are dependently driven and those of the other are independently driven. For each hand, we show locking and power transmission mechanisms. Power of each hand is transmitted from operator's hand to its fingers by connecting wires with a ball and socket. Experimental results verify that both hands can grasp large and oily objects like organs. When rod-shaped instruments are not enough to accomplish laparoscopic surgery, hand assist laparoscopic surgery is often applied. The goal of this study is to develop robot hands that can replace surgeons' hands in hand assisted laparoscopic surgery.

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