Trimble Navigation Limited

Hewlett-packard Company

James L Sorden

Mark Edward Nichols

Michael Timo Allison

Michael V McCusker

Eric A Klein

Peter Raby

Terry J Smith

A first position determining device at a known position transmits a data signal identifying the known position. A second position determining device is responsive to the data signal and movable to a position near but displaced from a survey point. The position of the second position determining device is determined relative to the known position, and the range and bearing of the survey point is determined relative to the second position determining device.

Location and generation of high accuracy survey control marks using satellites

A lane change alarm using data for a highway track. A highway track database provides geographical location points for a track of a highway lane. A differential global positioning system (DGPS) receiver provides a vehicle location. A longitudinal track matching code matches the vehicle location against a track location and provides a longitudinal direction and a transverse distance to an alarm gate. The alarm gate indicates an alarm condition unless a lane change signaler is operated for indicating that the lane change is intentional. The highway track database is created using a similar DGPS receiver by determining and recording highway track location points for a selected highway lane while driving on the highway lane.

Lane change alarm for use in a highway vehicle

An electronic distance meter comprises an integrated circuit from a GPS navigation receiver having a local pseudo-random number code generator for code demodulation that is connected to modulate either a polychromatic or a monochromatic light source. An optical system focuses the light on a distant target with an unknown range. Reflections from the distant target are focused on a light detector that produces a phase-delayed copy of the original pseudo-random number code. The time-of-flight to and back from the distant target is a function of the distance. The GPS receiver integrated circuit computes the range based on the code-phase delay to a precision better than one centimeter. The position of a remote target can be triangulated from several electronic distance meters each having known positions, e.g., determined by included GPS navigation receivers. Conversely, the position of a single electronic distance meter can be determined by triangulation by ranging to several remote targets each having known positions.

Code-space optical electronic distance meter

A method for accurately determining the location of a pre-selected survey or construction mark, or for accurately identifying the survey position for a new mark with pre-selected location coordinates. A Satellite Positioning System (SPS), such as GPS or GLONASS, with at least two SPS stations (antennas and receiver/processors) is used to receive and analyze SPS signals from four or more SPS signal satellites. An SPS signal reference station is placed at a position with known location coordinates, which can be stationary or be known functions of time. An SPS signal roving station receives the location coordinates of the reference station and determines its own location coordinates relative to the reference station, using SPS differential positioning. The roving station is then moved to a pre-selected survey mark or position, either to locate that survey mark or to identify (by marking) a new survey position from pre-selected location coordinates. The reference station analyzes the satellite signals received and transmits this measurement information and the reference station location to the roving station. The roving station independently makes similar measurements using satellites signals it receives. The roving station can contain a data-base of pre-selected positions that are to be located, which may or may not have corresponding physical marks. A handheld survey controller incorporating a visual or audible display is attached to the roving station, which guides the user to one or more of the pre-determined positions. Suitable radio communication apparatus is provided to allow the reference receiver to broadcast information to the roving receiver, even if the roving receiver is not directly visible from the reference receiver.

Location and generation of high accuracy survey control marks using

Apparatus that is carried on a land vehicle, a marine vehicle or vessel, or an airborne vehicle or vessel for notifying others that a vehicle accident or other abnormal situation has occurred and for notifying others of the location of the vehicle at the time of the accident. The vehicle carries an distance measuring system (DMS) signal antenna and receiver/processor that receives DMS-type signals from one or more DMS signal broadcasters and determines the present position of the vehicle, plus an activatable transmitter. The vehicle also carries an abnormality sensing means that senses the occurrence of an accident or other abnormal situation involving the vehicle or a vehicle occupant. When an abnormal situation is sensed, the abnormality sensing means automatically activates the transmitter, which then communicates the fact that an abnormal situation has occurred and the location of the vehicle at the time the event occurred. Alternatively, the abnormality sensing means can activate the transmitter only after a vehicle operator has taken affirmative action indicating that the transmitter should be activated. Optionally, the transmitter can also communicate the time the event occurred. If the abnormal situation is (1) a vehicle accident, (2) inoperability of the vehicle, (3) inability of the vehicle operator or other vehicle occupant to continue (e.g., because of a rapid change in a present health condition of the occupant), the transmitter can also communicate information on (1) the severity of the accident, (2) the type or cause of vehicle inoperability, (3) the reason the operator or other occupant is unable to continue. Optionally, the system can also transmit, or hold for future analysis, the values of one or more vehicle operating parameters sensed at a sequence of times preceding occurrence of the abnormal situation. The DMS may be a Satellite Positioning System, such as the Global Positioning System (GPS) or the Global Orbiting Navigation System (GLONASS), or a ground-based radionavigation system, such as LORAN, Shoran, Decca or TACAN.

Event-activated reporting of vehicle location

An averaging frequency counter for determining the frequency of recurrence of input signals has an event counter for counting a number of the input signals, a gate counter for counting a number of time intervals during which the input signals are counted, and a time interval measurement circuit for measuring the cumulative duration of the time intervals. A systematic error associated with the measurement of the duration of each time interval is determined during an application of a calibrated frequency to the averaging frequency counter by dividing a calculated total time error by the number of time intervals. The systematic error is subsequently used to correct a measurement of an unknown frequency during an application of the unknown frequency to the averaging frequency counter by subtracting a product of the number of the time intervals and the systematic error from the cumulative duration.

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Saratoga, CA, United States of America

James L Sorden