Recently, there has been significant research interest in homogeneous modular robots that can transform (i.e. reconfigure their overall shape). However, many of the proposed transformation mechanisms are too expensive and complex to be practical. The transformation process is also normally slow, and therefore the mechanisms are not suitable for situations where frequent, quick reconfiguration is required. To solve these problems, we have studied a transformable mobile robot composed of multiple homogeneous gear-type units. Each unit has only one actuator and cannot move independently. But when engaged in a swarm configuration, units are able to move rapidly by rotating around one another. The most important problem encountered when developing our multi-module robot was determining how units should join together. We designed a passive attachment mechanism that employs a single, six-pole magnet carried by each unit. Motion principles for the swarm were confirmed in simulation, and based on these results we constructed a series of hardware prototypes. In our teleoperation experiments we verified that a powered unit can easily transfer from one stationary unit to another, and that the swarm can move quickly in any direction while transforming.

We propose and develop a novel type of manipulator for the minute work. It can not only independently control the position and orientation of the end-effector, but also control the translational motion along with the axis of end-effector by only one actuator in any orientation. By this mechanism, it is able to achieve a larger workspace with high precision comparing with the traditional proposed manipulator for minute work. From the result of measurement of accuracy for our prototype manipulator, it is shown that the error of the end-effector tip is within 50.0 /spl mu/m and repeated positioning error is within 2.0 /spl mu/m in the changing orientation process.

A bilateral control system for scaled teleoperation provides the human operator with a feel of the task as well as the teleoperation between same-scale worlds. A maneuverability of the teleoperation system depends on the bilateral control scheme. This paper, first, reviews several bilateral control schemes for the scaled teleoperation, which have already been developed, and points out its dexterity issue of teleoperation. From these reviews with considering physical meaning of bilateral controllers, secondly, this paper proposes a novel bilateral control scheme that realizes macro-micro teleoperation with natural force feedback sensation. An idea of control scheme is come by taking notice that the system parameter values of master site and those of slave site are different. This control scheme is based on operational force feedforward type bilateral control with scaling gains. We also study the operational feeling of the proposed control scheme and compare with several bilateral control schemes in theory. Finally, we present experimental results that verify the validity of the proposed control scheme.

In the teleoperation between different-scale worlds, it is important to consider the scaling effect problem. An impedance shaping bilateral teleoperation that considers this problem is needed to provide the human operator with natural sensation while tele-manipulating objects in the micro world whose main physical characteristics are different from those in the macro world. In this paper, we propose a bilateral control scheme which provides the operator with an impedance shaped out of the real one. This control scheme is based on force feedback bilateral control with scaling transfer function gains. By choosing not only the geometrical scaling gains but also the dynamic scaling ones as the scaling transfer function gains, the impedance that is presented to the operator can be shaped out of the real one. Finally, we present experimental results that verify the validity of the proposed control scheme.

This paper present the design concept of a power assist system. In such system, when the controller is designed without considering the maximum torque of the actuators, the actuators can sometimes become saturated, resulting in a loss of stability and manoeuvrability. We propose a method for dealing with this problem. The load force is divided into gravitational and dynamic component, and each component is attenuated by an individual ratio. These ratios are determined considering the maximum power of the operator and the actuators.

Identifying and implementing high fidelity scaling laws in scaled teleoperated systems is still a challenge. We propose the use of additional information (e.g., auditory and tactile) to complement and supplement the normal visual and force channels and thereby provide sensory enhancement when performing delicate tasks. We support our proposal by presenting experimental results from tests performed by humans on a hybrid hardware-software telemanipulation system. Our results show that integrating auditory and tactile feedback improved the performance of the operator.