Stereoscopic human interfaces

This article focuses on the use of stereoscopic video interfaces for telerobotics. Topics concerning human visual perception, binocular image capturing, and stereoscopic devices are described. There is a wide variety of video interfaces for telerobotic systems. Choosing the best video interface depends on the telerobotic application requirements. Simple monoscopic cameras are good enough for watching remote robot movements or for teleprogramming a sequence of commands. However, when operators seek precise robot guidance or wish to manipulate objects, a better perception of the remote environment must be achieved, for which more advanced visual interfaces are required. This implies a higher degree of telepresence, and, therefore, the most suitable visual interface has to be chosen. The aim of this article is to describe the two main aspects using stereoscopic interfaces: the capture of binocular video images, according to the disparity limits in human perception and the proper selection of the visualization interface for stereoscopic images

Real-time kinematics for accurate geolocalization of images in telerobotic applications

The paper discusses a real-time kinematic system for accurate geolocalization of images, acquired though stereoscopic cameras mounted on a robot, particularly a teleoperated machinery. A teleoperated vehicle may be used to explore an unsafe environment and to acquire in real-time stereoscopic images through two cameras mounted on top of it. Each camera has a visible image sensor. For night operation, or in case temperature is an important parameter, each camera can be equipped with both visible and infrared image sensors. One of the main issues for telerobotic is the real-time and accurate geolocalization of the images, where an accuracy of few cm is required. Such value is much better than that that provided by GPS (Global Positioning System), which is in the order of few meters. To this aim, a real-time kinematic system is proposed which acquires the GPS signal of the vehicle, plus through an RF channel, the GPS signal of a reference base station, geolocalized with a cm-accuracy. To improve the robustness of the differential GPS system, also the data of an Inertial Measurement Unit are used. Another issue addressed in this paper is the real-time implementation of a stereoscopic image-processing algorithm to recover the 3D structure of the scene. The focus is on the 3D reconstruction of the scene to have the reference trajectory for the actuation done by a robotic arm with a proper end-effector

Aerospace medicine and biology: A continuing bibliography with indexes (supplement 341)

This bibliography lists 133 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during September 1990. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance

Operator vision aids for space teleoperation assembly and servicing

This paper investigates concepts for visual operator aids required for effective telerobotic control. Operator visual aids, as defined here, mean any operational enhancement that improves man-machine control through the visual system. These concepts were derived as part of a study of vision issues for space teleoperation. Extensive literature on teleoperation, robotics, and human factors was surveyed to definitively specify appropriate requirements. This paper presents these visual aids in three general categories of camera/lighting functions, display enhancements, and operator cues. In the area of camera/lighting functions concepts are discussed for: (1) automatic end effector or task tracking; (2) novel camera designs; (3) computer-generated virtual camera views; (4) computer assisted camera/lighting placement; and (5) voice control. In the technology area of display aids, concepts are presented for: (1) zone displays, such as imminent collision or indexing limits; (2) predictive displays for temporal and spatial location; (3) stimulus-response reconciliation displays; (4) graphical display of depth cues such as 2-D symbolic depth, virtual views, and perspective depth; and (5) view enhancements through image processing and symbolic representations. Finally, operator visual cues (e.g., targets) that help identify size, distance, shape, orientation and location are discussed

Real-time, interactive, visually updated simulator system for telepresence

Time delays and limited sensory feedback of remote telerobotic systems tend to disorient teleoperators and dramatically decrease the operator's performance. To remove the effects of time delays, key components were designed and developed of a prototype forward simulation subsystem, the Global-Local Environment Telerobotic Simulator (GLETS) that buffers the operator from the remote task. GLETS totally immerses an operator in a real-time, interactive, simulated, visually updated artificial environment of the remote telerobotic site. Using GLETS, the operator will, in effect, enter into a telerobotic virtual reality and can easily form a gestalt of the virtual 'local site' that matches the operator's normal interactions with the remote site. In addition to use in space based telerobotics, GLETS, due to its extendable architecture, can also be used in other teleoperational environments such as toxic material handling, construction, and undersea exploration