A tension controller for the tether system using the 50 kg-class microsatellite, which has been studied mainly by National Aerospace Laboratory in Japan, is designed. First, the optimal reference motion of the system is designed by using a simple model that ignores the tether flexibility. Then, the controller to make the system track the reference motion is designed by also using the simple model. The effect of the tether flexibility is not considered in the design of the controller, but is dealt with as disturbance in this simple model. In order to make a reference motion that is easy to follow, a certain measure of the difficulty of tracking is selected as the objective functional, which is to be minimized. Finally, the tracking controller is applied to the model in which the tether flexibility is considered to test how the designed controller can deal with flexibility. The validity of the controller is verified through numerical simulations.

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The purpose of this study is to establish the technique of solving large scale problems associated with multi-body dynamics simulation and to break through the limitations imposed on the traditional methods. It is necessary to compute on computer, which is faster and has larger memory, for multi-body analysis of LSS. But, the sequential algorithm of numerical computation on traditional computer such as PC, EWS, and vector supercomputer has the limitation of capability itself. We have been developing a multi-body dynamics simulation code which is called CNBODY(Constrained N BODY), and renewing for parallel multi-processor computer. The algorithm of CNBODY has been established based on a unified matrix method which is called extended inertia matrix. It is very important to solve the linear system with efficiency for the large scale problem. On distributed parallel machine, the large size extended inertia matrix is divided some regions and set on each node(processor) by appropriate manner. The new CNBODY has several data distribution method, and solves the linear system by direct method. This is a report about the part of performance new CNBODY.

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In this paper, the authors propose an image processing technique for supporting ground-based teleoperation using texture mapped lifelike images, and show some results of a flight experiment conducted as a part of the Manipulator Flight Demonstration (MFD) space shuttle flight experiments operated by NASDA on the STS-85 mission launched on July 17, 1997. In the experiment, the quality of the virtual multiple view images and the time needed for generation were evaluated, and the results have shown an improvement, over existing user interfaces in interpreting the real time status of a remote manipulator system during teleoperation.

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When the vehicle which attaches conducting coils moves across planetary magnetic field, an electromotive force arises and supplies current and power to certain electrical equipment. We show this power supplying mechanism and discuss about the validity as power supply system.

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