A bilateral master-slave control method for manipulators with different configurations is proposed to efficiently control remote robots working in harzadous and critical fields such as nuclear power plants, space and underwater. In this method any types of master device and slave manipulator are able to be connected with each other. Therefore it has some advantages over the conventional method in which the same types of master device and slave manipulator are employed. The first advantage of this method is to improve manoeuvrability in operation, the second to increase versatility and the third to be applied to a teaching operation of complex tasks in industries. The basic experiments using three types of manipulators have been done to check the feasibility of the proposed method. In these experiments the force trackerbility, the position trackerbility of the slave and the computing time of the digital computer required for the operations of coordinates transformations, position and force servos, are examined. The results of these experiments and more practical experiments, such as a crank turning motion, show the reasonable feasibility and the broad applicability of the proposed method.

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A high performance teleoperation system is required to carry out tasks of various kinds efficiently in critical and hazardous areas in place of human beings. The bilateral control method for manipulators with different configurations has been proposed to provide the conventional master-slave control method with good manoeuvrability and dexterity. In this paper the improvement of the formerly proposed method is considered. In the newly developed method manipulators with different numbers of degrees of freedom as well as different configurations are able to be used. In the process of coordinate transformations the concept of the common space and its subspace is introduced. The basic experiments using two types of manipulators with two and three degrees of freedom have been done to check the feasibility of the method. The effect of the joint dynamics is analyzed and its compensation methodd is also discussed.

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In this paper, the mechanics of coordinative manipulation by multiple robot manipulators or a multi-fingered robot hand is discussed. The coordinative manipulation problem is divided into two phases. One is determining the resultant force by multiple robotic mechanisms, and the other is determining the inner force between them. The resultant force is used for the manipulation of an object subjected by external forces or environmental constraints. The inner force is used for adapting the mechanisms to uncertainty or variety of the maximum static friction coefficient. Dynamic coordinative control scheme is proposed for determining the resultant forces. A method is also proposed to verify the coordinative manipulation ability, that is, the ability for generating an arbitrary acceleration of the object under the constraints of the maximum static friction. Finally, the optimal inner force is defined as the minimal-norm inner force necessary for satisfying maximum static friction constraints, and a non-linear programing method is applied to obtain the optimal solution. The optimal solution is necessarily obtained by solving, at most, mΣj=1 jΣi=0 _jC_i sets of algebraic equations, as long as it exists.

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A locomotive robot have to avoid moving obstacles not only fixed obstacles.
This paper describes a solution of the collision avoidance problem of a locomotive robot for a moving ostacle.
The presented solution includes three steps.
The first step is a method to evaluate a dangerous states of a colliding obstacle.
The second is a method to plan a collision avoidance route against a colliding obstacle.
The third is a method to control a velocity of a robot.
And we also show the result of computer simulation of moving collision avoidance behavior of a robot based on presented methods.

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