Patent Application
20100204919
Whenever military or emergency medical services are performing landing in the field, often there are obstacles that must be avoided when approaching the landing zone. Avoiding these obstacles is imperative to a successful landing. The problem becomes acute at night when visibility is reduced. A device that could automatically survey a site to locate and map obstacles would greatly improve the operation ability and safety of these types of landings and significantly expand the areas into which landings could safely occur.
In an embodiment, an imaging system includes a processor, a detection assembly configured to collect survey data characterizing a respective height and location of physical features of a geographic region, a receiver assembly configured to provide location data characterizing a geolocation of the geographic region, a tilt sensor configured to provide tilt data characterizing an inclination of the detection assembly with respect to gravity, and a magnetic-field sensor configured to provide field data characterizing a magnetic field associated with the geographic region. The processor is configured to perform processing of the survey data and tilt data to yield a first corrected data set, obtain magnetic-deviation data associated with the geographic region, determine an indication of true north, and process the first corrected data set and true-north indication to yield a second corrected data set comprising the first corrected data set oriented to true north.
Preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings.
An embodiment of the invention automatically surveys the terrain of a target landing zone for dimensions and locations of potential obstacles to landing therein. This survey information is corrected for inclination of the surveying system of the embodiment and oriented to true north. The resultant data is processed to produce a three-dimensional image or map of approaches to the landing zone, as well as the landing zone itself This data and/or the 3-D image can be transmitted to the flight crews of one or more aircraft desiring to enter the landing zone. Using this data, the flight crews can plot a safe approach to the landing zone through a virtual image of the obstacles. Alternatively, the survey data can be used to calculate safe approach paths consisting of directions and altitudes, and the safe approaches and this information can be transmitted to the flight crews of one or more aircraft desiring to enter the landing zone. An embodiment may be mounted to, or otherwise carried by, a platform, such as a stationary platform or a mobile platform, such as a manned aircraft, an unmanned aerial vehicle, or a land-based vehicle.
The invention may be described in the general context of computer-executable instructions, such as program modules, executed by one or more computer processors or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Typically the functionality of the program modules may be combined or distributed as desired in various embodiments.
Referring again to
In operation, and in an embodiment, the system 10 is brought into a proximity of a desired landing zone 34 (
The rotating LIDAR unit 14 is then programmed, or is otherwise configured, to automatically scan the terrain of the landing zone 34 and approach zone 36 to survey one or more obstacles 32 (e.g., trees, rock formations, buildings, etc.) present therein. More specifically, the LIDAR unit 14 may determine the locations/coordinates and one or more dimensions (e.g., height and/or area) of a predetermined threshold dimension (e.g., minimum height and/or area of a specified measurement-unit quantity) of the obstacles 32. The LIDAR unit 14 may be moved or transported to other locations in the landing zone if necessary to gain a complete picture of the landing zone.
The inclinometer 18 is configured to measure a tilt angle of the LIDAR unit 14 with respect to a reference, such as gravity. This tilt-measurement information may then used by the computer 12 to correct the measured obstacle dimension and location.
The GPS receiver 16 is configured to provide the geolocation of the landing zone 34. The magnetometer 20 is configured to provide field data characterizing the terrestrial magnetic field associated with the location of the system 10. The magnetometer 20 and inclinometer 18 combine to provide the functionality of a three-axis compass that indicates to the computer 12 the direction of magnetic north, regardless of the tilt angle of the magnetometer. Alternatively, the direction of magnetic north may be determined using solely the field data provided by the magnetometer 20.
The system 10 may further include a memory device 50 operable to store data retrievable by the computer 12. Specifically, the memory device 50 may be configured to store a look-up table of magnetic-field-deviation data associated with the GPS position of the zones 34, 36. Alternatively, the field-deviation data may be stored in a location external to the system 10 and retrievable by the computer 12. The computer 12 may use this field-deviation data to correct the magnetometer 20 measurement of north relative to true north. Consequently, the orientation of the survey data collected by the LIDAR unit 14 can be oriented relative to true north without having to physically rotate or otherwise reorient the system 10 to align with true north.
Subsequently, the comprehensively corrected data can be processed by the computer 12 to produce a three-dimensional obstacle map referenced to the GPS position of the zones 34, 36. For example, such a map may depict a virtual rendering of the location and orientation of the detected obstacles 32, as well as numerical data characterizing the coordinates and dimensions of the obstacles. Additionally, the map may be produced in a format allowing a heads-up or other display, in conjunction with onboard aircraft avionics, to provide a full-motion 3-D virtual image of obstacles 32 present in the approach and landing zones 34, 36 and corresponding to the aircraft's movement therethrough.
The radio link 22 and antenna 24 can be used to transmit the corrected data and or data representing the 3-D GPS-referenced map to the flight crews of selected aircraft desiring to approach and land in landing zone 34, or to a centralized collection point for distribution to pilots flying to the landing zone.
As illustrated in
While a preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow.
