This paper describes a ground experiment system for space robots based on an improved version of predictive bilateral control and the results of simulated space telemanipulation experiments. The predictive bilateral control provides both the predictive and virtual contact forces/torque along six degrees of freedom by a force reflected master-arm. The virtual contact forces are produced by the collision with a virtual guide model to move the slave-arm to a desired position quickly and safely. Ground simulation models can be calibrated by means of visual sensing using target marks. The simulator for previewing is designed to be reconfigurable by modularizing the basic functions. The system executes tasks including manual operations according to a program written in an interpreter language for interactive operations. Coupling experiments using ETS-VII Antenna Assembling Mechanism (AAM) and peg-in-hole tests were carried out to evaluate the system's effectiveness and the results obtained demonstrate that it is in fact effective. Currently, we are improving the system for the use in actual ETS-VII AAM experiments in space.

This paper presents a dual-resolution local sensor based planning method for hyper-redundant robot mechanisms. Two classes of sensor feedback control methods, working at different sampling rates and different spatial resolutions, are considered: full shape modification (FSM), and partial shape modification (PSM). FSM and PSM cooperate to utilize a mechanism's hyper-redundancy to enable both local obstacle avoidance and end-effector placement in real-time. These methods have been implemented on a thirty degree of freedom hyper-redundant manipulator which has 11 ultrasonic distance measurement sensors and 20 infrared proximity sensors. The implementation of these algorithms in a dual CPU real-time control computer, an innovative sensor bus architecture, and a novel graphical control interface are described. Experimental results obtained using this test bed show the efficacy of the proposed method.

This paper describes a telerobot system and its application to space antenna assembly experiments. In this system, the operator utilizes an Integrated Teleoperation Console to operate multiple arms and cameras from a remote site, employing such system supports as visual guidance, ForcelTorque sensing, interactive user interface, and real-time graphic kzsk simulation. Visual guidance is semi-autonomous in that the robot itself is also capable of interpreting visual information and grasping target objects. In the study, assemblyldisassembly experiments are carried out on an space antenna consisting of a center dish surrounded by eight separate outer antenna segments. The accuracy of visual guidance positioning is evaluated experimentally. Results prove the effectiveness of both the telerobot experiment system and the space antenna structure. investigate this system's potential effectiveness for use in space. The antenna used was a version with improved assembly reliability. The positioning accuracy of the semi- autonomous visual guidance system was first evaluated experimentally, and then multiple segments were assembled and disassembled. In the segment grasping stage of the assembly experiments, the segment holder position was shifted to verify visual guidance. Positioning shifts were intentionally applied to robot motion commands in the assembly stage of the experiments to simulate actual robot motion in space. In spite of these shifts, accurate coupling was successfully achieved and the effectiveness of the system demonstrated.

A high-sample-rate robot controller has been designed to resolve computational requirements in advanced algorithms, such as the computed torque method or various impedance control algorithms. An active stiffness control algorithm for a six-degree-of-freedom manipulation has been implemented on the controller, and a 1 kHz sampling rate has been achieved. The design assumes no specific algorithm and robot configuration, and it is easy to increase the number of drive joints. The controller is equipped with a general-purpose vector/matrix calculation engine, servo drivers, and a 16-bit microcomputer system. The calculation engine, which accelerates hole computation for advanced control methods, is based on a 13.4 MFLOPS single-chip floating-point digital signal processor (DSP). This engine was developed to simplify DSP programming without degrading its high-performance computation capabilities. Basic vector/matrix functions and general functions for scalar value computation are mask ROMed on the DSP chip. The controller construction and calculation engine functions, and their performance, are addressed.>