Masahiko Minamoto

Tele-presence information and remote-controlled task execution

We developed a remote-controlled system which enabled us to effectively control remote construction machinery such as a backhoe shovel, wheel dump and bulldozer using video images at a safe distance and in a comfortable environment. We used this system for one year at Mt. Fugen, an active volcano in Shimabara City of Nagasaki Prefecture, which is known for the disaster in which a large scale pyroclastic eruption killed many people.

New stereoscopic video camera and monitor system with central high resolution

A new stereoscopic video system (the Q stereoscopic video system), which has high resolution in the central area, has been developed using four video cameras and four video displays. The Q stereoscopic camera system is constructed using two cameras with wide-angle lenses, which are combined as the stereoscopic camera system, and two cameras with narrow-angle lenses, which are combined (using half mirrors) with each of the wide-angle cameras to have the same optical center axis. The Q stereoscopic display system is composed of two large video displays that receive images from the wide-angle stereoscopic cameras, and two smaller displays projecting images from the narrow-angle cameras. With this system, human operators are able to see the stereoscopic images of the smaller displays inserted in the images of the larger displays. Completion times for the pick-up task of a remote controlled robot were shorter when using the Q stereoscopic video system rather than a conventional stereoscopic video system.

Effects of visual information on a remote-controlled robot

To efficiently perform work using a remote-controlled robot, an image display device that allows the operator to verify the working area from a single view is necessary. Furthermore, this device should provide high-resolution images of locations so that the operator can recognize depths in detail. To meet these requirements, conventional three-dimensional image devices used multiple cameras and display screens for the right and left eye. In this study, we developed a camera device using a camera and a display, which can provide a wide-range view while providing high resolution for the central part of images using a mirror. We evaluated the effectiveness and verified that operators can accurately conduct a remote operation in a short period of time; this was possible using high-definition spatial information from a composite screen and continually adapting to changes in the surrounding environment that could be viewed at a wide range. The experiment also revealed that the composite screen ratio can be altered as required.

Effects of visual information on a remote-controlled mobile robot

To efficiently perform work using a remote-controlled robot, an image display device that allows the operator to verify the working area from a single view is necessary. Furthermore, this device should provide high-resolution images of locations so that the operator can recognize depths in detail. To meet these requirements, conventional three-dimensional image devices used multiple cameras and display screens for the right and left eye. In this study, we developed a video device that employs a camera and a display, which records a wide range while providing high resolution for the central part of the images using a mirror. The effectiveness of our device was confirmed through an evaluation experiment using a remote-controlled work robot. The results indicated that using the transmitted complex display, the operator can utilize high-precision space information and respond to a wide range of changes in the surrounding environment. It was thus confirmed that the remote-controlled operation could be conducted with improved accuracy and in a shorter time.

Effect of robot operation by a camera with the eye tracking control

In this paper, we develop a control system for tele-operation of robots using an eye tracking control and confirm its effectiveness by experiments. A camera mounted on the robot provides a view to an operator via a monitor screen. The screen is divided into 3×3 grids. The robot stops when the gaze is on the center grid cell. When the gaze is on the other gird cells, the robot moves to the direction with a pre-defined constant speed. We apply the developed system to control a laparoscope holder robot and a crawler-type rescue robot. In the laparoscope holder robot, no sensor needs to be attached on the operator with the system while a gyroscope is mounted on the conventional system. In the tele-operation of the rescue robot, the control system is used to view the robot from an operation room. The travel time of a narrow pilot road becomes shorter in the proposed control system than the verbal instruction to the camera operator.

Effect of force feedback on a bulldozer-type robot

Utilizing remote-controlled robots in damage restoration activities in disaster-affected areas such as those affected by a debris avalanche or an earthquake has significantly increased. Various types of remote-controlled robots have been successfully used along with construction machines in damage restoration activities in disaster-affected areas. Recently, a bulldozer-type robot removed the earth and sand deposited over a wide area because of a debris avalanche. To enable prompt damage restoration activities in disaster-affected areas, an efficient remote operation using robots is required. We study a remote-controlled bulldozer-type robot that moves objects using a system wherein the status of the stress applied on the bulldozer blade is provided as a force feedback to the operator. After conducting evaluation experiments, we could verify that the operating system providing force feedback to the operator shortened the operation time compared with the one that displayed visual information only on the operating screen.