Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
  • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
  • G01C21/10—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration
  • G01C21/12—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning
  • G01C21/16—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
  • G01C21/165—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation combined with non-inertial navigation instruments
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
  • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
  • G01S19/13—Receivers
  • G01S19/14—Receivers specially adapted for specific applications
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
  • G01S19/38—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system
  • G01S19/39—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system the satellite radio beacon positioning system transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
  • G01S19/53—Determining attitude

Definitions

• the present in ention relates to a camera guidance system as described in the preamble to re ⁇ end ⁇ cat ⁇ on 1
• GPS svstems Global Positioning Svstems
• IMUs inertial measurement units
• the attitude of a target, camera, platform or relay station more generally called an object, equipped with only a GNSS receiver and an IMU can be determined provided that this object moves with sufficient speed on any path the three-dimensional space speed must simply be sufficient to allow proper operation of the MU, but need not be predetermined, nor is the trajectory of the object such svstem is functionally comparable to a svstem attitude determination comprising several GNSS receivers, but the same receiver is used here to measure several different positions in three-dimensional space While the position measurements by this receiver are made at time intervals, the IMU is used
• IMU measurements are vitiated by errors known as de ⁇ ve errors, but these errors can be easily corrected by adapting the duration of the intervals separating two GNSS measurements to the required precision These GNSS measurements, more precise, allow these errors to be controlled expires at the end of each interval
• the trajectory of the objects or vehicles is not arbitrary, but is insc ⁇ te within known and listed limits, such as for example the track of a racing circuit
• the limits of the track and its three-dimensional topography comprising for example altitude variations, crossing of passes, bridges, and more particularly tunnels, can be pre-recorded by the information processing movens From then on, the position and the attitude of a vehicle or object fitted simply with an IMU, and moving within such known and pre-recorded limits, can be determined by correlation of the three-dimensional accelerations and rotations recorded by the IMU
• This correlation process has moreover, sufficient information to also calculate the deviation errors of the accelerometers of the IMU and its gyroscopes II is simply t necessary to obtain really precise results, that the vehicle or object approaches from time to time the trajectory limits, like the edge of the track in the aforementioned case More precisely, when the vehicle or object grazes the edge of the track caused by the change of surface are immediately detected by
• the initialization of the system can be facilitated and made faster if the means for processing the information is supplied with additional indicia of orientation, for example by signals emitted by a photoelectric cell arranged on the trajectory
• additional indicia of orientation for example by signals emitted by a photoelectric cell arranged on the trajectory
• the location of the cell is recorded in the memories of the information processing means, and the signals , emitted by the cell each time a vehicle or object passes in front of this cell, then allow the system to follow with ce ⁇ itude the evolution of the position of the vehicle or object
• wheel rotation sensors or bodies direction are arranged on the objects to provide the movens of information processing with additional data.
• the GNSS satellites can be replaced by pseudo-satellites, commonly known recently as "pseudolites", which are mounted in the immediate vicinity of the ceiling of the room.
• pseudolites have functions comparable to GNSS satellites and can effectively provide platforms and cameras with the data necessary for taking pictures of targets, via information processing means
• the cameras are at least two in number, and the information processing means have the capacity to analyze the filmed images.
• This capacity allows the system to operate without having to the need, for the objects, to constantly provide data for the calculation of their position and attitude by the information processing means
• the information processing means analyze the images filmed by this camera, the position of which is known by the information processing means It is then possible to recognize one or more targets by image analysis and undertake an estimation of their position in the plane considered, even if these c ibles do not directly transmit information about their position or movement.
• This estimate can be refined in a similar way by one or more other cameras, closer to the targets, the position of which is also known by the information processing means. Thanks to such image analysis capabilities, the system can work even with non-cooperating targets, i.e. targets that do not directly reveal their position.
• GNSS pseudolites in an indoor sports event or demonstration.
• Sources of electromagnetic signals are arranged on the pseudolites, themselves fixed in the immediate vicinity of the room ceiling, for example in the manner of ceiling lights.
• the distance separating these various sources electromagnetic signals from receivers, or points of reception or transmitters of these signals is measured and used as a basis for calculations of information processing movens, aimed at determining the position of these receivers or reception points
• the speed of the signals concerned is close to the speed of light, and the distance traveled by a signal is evaluated using the time taken by this signal to travel the distance from the source or a transmitter to a receiver or point.
• FIG. 1 represents a target filmed by a camera on its platform
• FIG. 2 shows an embodiment with at least two cameras and non-cooperating targets
• the system represented in FIG. 1 comprises a target 8, equipped with a receiver
• This assembly comprising the platform 7 moves on a t ⁇ -dimensional trajectory
• Platform 7 is equipped with a GNSS receiver and an IMU (not shown)
• the IMU Simultaneously with these position measurements by GNSS, the IMU also records the accelerations undergone by the platform, and also measures the position of points 3, 4 and
• Information processing movens use these position measurements (which must be at least six in number) to calculate the precise position and attitude of platform 7, i.e. its Euler angles by relative to the fixed reference 2
• the position of the target 8 is determined by its GNSS receiver
• the information processing movens then deduce from the position of the target 8, as well as from the position and attitude of the platform 7, the camera pointing angles relative to the platform, as well as the zoom data of this camera, to keep the target 8 in the field of the camera at all times with the desired focus
• FIG. 2 represents the concrete case of a car race filmed by at least two cameras
• One of these cameras is on board an aircraft 9 flying over the racing circuit, which in the present case does not include tunnels
• the processing means information include capabilities for analyzing the images filmed by this camera and estimate the position of targets 10 and 1 1, which are two competitors of the race They provide the second camera 12 with elements of guidance to the most suitable target, for example 10, but which can be chosen according to criteria known per se, for example from the request PCT / IB94 / 0043 1
• the second camera 12 also provides images capable of processing by the abovementioned scanning capabilities, which makes it possible to refine the position location of the selected target 10, and allow a satisfactory framing of this camera
• the shots taken are commercially exploitable, particularly when the camera is located at a location considered too dangerous to risk the life of a cameraman, such as for example in the immediate vicinity of the runway. It is conceivable that the two cameras, thanks to the capabilities analysis of images associated with these cameras, help each other in monitoring the chosen target 10 assumed to be non-cooperative

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• Engineering & Computer Science (AREA)
• Radar, Positioning & Navigation (AREA)
• Remote Sensing (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Automation & Control Theory (AREA)
• Computer Networks & Wireless Communication (AREA)
• Position Fixing By Use Of Radio Waves (AREA)
• Navigation (AREA)

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Publications (1)

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Family Applications (1)

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• 1997
  • 1997-10-24 WO PCT/CH1997/000405 patent/WO1998019176A1/fr not_active Application Discontinuation
  • 1997-10-24 EP EP97944674A patent/EP1025452A1/de not_active Withdrawn

Non-Patent Citations (1)

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