Showing papers on "Turn-by-turn navigation published in 1988"

Visual Attentional Demand of An In-car Navigation Display System

Abstract: Two research studies were performed in which an operational in-car navigation display system was tested and evaluated. In the first study, the visual attentional demand requirements for specific tasks associated with the navigation system were compared with those of a wide variety of conventional (though modern) instrument panel tasks. The purpose in gathering these data was to evaluate whether or not the navigation tasks created demands that were greater than those of conventional tasks, and if so, by how much. The second study addressed the effectiveness, efficiency, and strategy associated with three different kinds of route guidance, memorized route, conventional paper map, and the navigation system. Results of the studies indicate that drivers are able to use the navigation system effectively and that it compares favorably with paper maps. However, visual scan patterns are changed when using the navigation system. Furthermore, drivers use a visual sample process which is quite different from that used for either paper maps or memorized route. Other findings indicate that the visual attentional demand of most navigator tasks is within the range of that for conventional tasks, however, a few tasks do have high visual attentional demand. These latter tasks could be modified to reduce their visual attentional demand.

System of navigation for vehicles

Abstract: A system of navigation for vehicles is proposed, which is provided with a device (14) for representing a road map as well as with a composite navigation apparatus (10, 11, 12) for the continuous instantaneous determination of the location of the vehicle and with a location display (16) on the representation of the road map. Deviations of the location from the course of the roads on the road map are detected and corrected. In order to be able to input a desired trip route (21) into the navigation system without an additional representation of the road map, prior to the beginning of the trip the desired trip route is traced by hand, using an input device (17, 18) connected to a trip route memory, with a wand (19) on the existing representation (14) of the road map, and thereby stored in the trip route memory (13). (Fig. 1).

Concepts and technology for navigation equipment

Abstract: The author reviews technology for supporting automated vehicle navigation. This technology ranges from simple map displays showing the current location of the vehicle to complex interactions between onboard electronics and a supporting infrastructure to provide intelligent guidance on the selection of driving routes. It is concluded that an infrastructure-intensive route guidance environment does not provide the functionality, the reliability, the flexibility, the coverage, or the performance that is necessary to make in-vehicle navigation viable in the marketplace. It is further concluded that distributed route guidance does provide these characteristics, using proven technology, at significantly lower costs than central systems. >

Global Positioning System (GPS) Autonomous User System

Abstract: A GPS autonomous navigation system will be operational with the GPS Block IIR satellites in the first decade of the twenty-first century. This system will provide the user with full navigation accuracy for 180 days even if the GPS Operational Control Segment (OCS) is inoperable. Until such a system is operational, GPS navigation accuracy depends on a functioning OCS. If the OCS fails, the navigation accuracy degrades rapidly. To provide interim full-system accuracy in the event of loss of the OCS, an Autonomous User System (AUS), requiring user segment modification only, has been designed, implemented, and field tested. In this paper, the AUS is described, and test results are presented. These results indicate that, in the 180-day period, the autonomous user can achieve a navigation accuracy of the same order of magnitude as is obtained when the OCS is functioning. The AUS concepts are also applicable to other navigation systems.

Hyperpyramids For Vision-Driven Navigation

Abstract: If an autonomous vehilce is to operate in an environment of arbitrary complexity, it must be able to perceive the locations of the obstacles in its environment and store this information in a world model. It is important that the world model be structured in such a manner that the information may be easily utilized. An object-oriented data structure called Hyper-Pyramids is presented for representing the environment in the navigation problem. A summary of preliminary research efforts on the navigation problem is also presented. This includes work on the implementation and manipulation of octtree-like data structures, and the introduction of a new technique for the recovery of depth information from grey-scale images.