Location device with a gravity measuring device

A location device has a gravity measurement instrument in communication with a database which has the locations relative to time of an astronomical object. The location device also has a timepiece indicating the time which may be used to determine the location of the astronomical object.

BACKGROUND OF THE INVENTION

In many instances the location of an object may be critical to the success of a project. Many locating systems such as Global Positioning Systems have been implemented to assist in the location of objects.

U.S. Pat. No. 5,379,224 which is herein incorporated by reference for all that it contains, discloses a Global Positioning system used in applications involving radiosondes, sonobuoys, and other objects. The GPS data is processed in a data processing workstation where the position and velocity of a sensor, at the time the data was sampled, is computed. A data buffer in the sensor is periodically refreshed, and the workstation periodically computes the new position and velocity of the sensor.

U.S. Pat. No. 5,983,161 which is herein incorporated by reference for all that it contains, discloses GPS satellite ranging signals at one of a plurality of vehicles/aircraft/automobiles that are computer processed to continuously determine the one's kinematic tracking position on a pathway with centimeter accuracy.

These types of systems have been useful in the locating of certain objects. However, these types of systems generally depend on satellite communication to function appropriately. In places where satellite communication may be impeded alternatives may be useful.

BRIEF SUMMARY OF THE INVENTION

A location device has a gravity measurement instrument in communication with a database which has the locations according to time of an astronomical object. The location device also has a timepiece indicating the time which may be used to determine the location of the astronomical object.

The location device may measure the gravitational force of least two astronomical objects creating two vector directions. Between these two vector directions an angle is formed that may be used in finding the position of the location device.

In another aspect of the invention a method comprising the steps of providing a gravity measurement instrument at a position within the universe may be used to locate the position of the gravity measurement instrument. The gravity measurement instrument may be in communication with a database that comprises the locations of at least two astronomical objects. Each astronomical object may provide a gravitational force on the gravity measurement device, creating a gravitational field. The method may further comprise measuring the gravitational field of the gravity measurement instrument; and calculating the position of the gravity measurement instrument from the gravitational field by determining a vector direction of the gravitational force from each astronomical object. Generally, a gravitometer is used in the measurement of gravitational forces. Types of gravitometer may include a zero length spring, a Lacoste gravitometer, a relative gravitometer, an absolute gravitometer, a superconducting gravitometer, or a combination thereof. Generally, the gravity measurement instrument comprises a quartz material, metallic material, elastomeric material, plastic material, or a combination thereof.

The location device may be placed in various places such as caves, cities, jungles, a plane, a submergible machine, a space shuttle, or beneath the surface of an astronomical object. In some embodiments, the location device may be used as an alternative to the commonly used GPS such as in cases where the communication between the location device and GPS satellite is blocked, or in other embodiments it may be used as a primary locating device. The location device may also be placed on a plane, a submergible machine, a space shuttle, a person, or on or in the surface of an astronomical object. The location device may be of particular importance in downhole operations such as mining and drilling operations. The location device may be deployed within a tool string or on a mining machine. The location device may further be placed within a housing that may protect it from harsh conditions. It may be of importance that the gravity measurement instrument be stationary relative to the astronomical object upon which it is positioned. Astronomical objects that may create a gravitational force on the gravity measurement instrument may include the Earth, the sun, the moon, a comet, a star, or a combination thereof. The database may comprise the locations of the astronomical objects which may be previously known or predictable. The astronomical object may move relative to the gravity measurement instrument. The gravity measurement instrument may be able to measure the gravitational forces as the astronomical object moves. The various gravitational forces and locations of the astronomical object at various positions may be recorded to the database.

In some embodiments of the present invention, the gravity measuring device may be part of an array of gravity measuring devices which may also be used to aid in determining a size, a boundary, a volume and/or a density of an astronomical object in part or in whole, such as mineral accumulations or hydrocarbon deposits. In some embodiments, tides or other local effects may be determine through the use of multiple gravity measuring devices.

FIG. 1is an orthogonal diagram of a derrick100aattached to a tool string101acomprising a location device103a. InFIG. 1the location device103ais placed downhole in the tool string101abeneath the surface of the Earth and may continue downhole as the tool string101aproceeds.

An astronomical object102may create a sufficient gravitational force that may be sensed by the location device103aand may create a vector direction107toward the astronomical object102. The astronomical object102may be the Earth, the moon, a comet, the sun, stars, or a combination thereof as long as its position and mass are accurately known. A second vector direction105may be generated from an astronomical object, such as a planet, upon which the location device103ais placed.FIG. 1shows one vector direction107generated by the moon and another vector direction105generated by the Earth upon which the location device is placed. With at least two vector directions105,107an angle106between the vectors105,107may be measured and may aid in locating the device103a.

Multiple location points may be taken and recorded as the location device proceeds downhole. The inclination, rotation, and direction of the tool string may also be taken into account by the location device. Measurements, such as those taken from instruments such as accelerometers, gyroscopes, magnetometers, or other inclination and direction instrumentation may add data which may be used to help determine the location of the location device.

In some embodiments, a second gravity measuring device150may be located uphole on the earth's surface which may be in communication with the downhole gravity measuring device and may be used to determine changes in gravity readings at the surface. These changes may be compared to the readings taken downhole to determine if an uphole or downhole anomaly is affecting the gravity measuring device. The gravity measuring devices may be in communication with each other through tool string telemetry systems such as wired pipe, mud pulse, radio wave, or short hop. In a preferred embodiment, a telemetry system such as the one described in U.S. Pat. No. 6,670,880, which is herein incorporated by reference for all that it discloses, may be incorporated with the present invention.

The embodiment ofFIG. 2is a cross-sectional diagram of a drill bit200acomprising a location device103bin communication with a database201a. In some embodiments the database201amay be located uphole. The drill bit200acomprises a body202aintermediate a shank203aand a working surface204a. The location device103bmay be placed in a housing in the drill bit200aor farther up the tool string. The location device103bmay also be in communication with a timepiece290athat may indicate the location time of an astrological object, and may be located uphole or downhole. The database201amay comprise the locations relative to time of an astronomical object. The location device103bmay comprise a gravity measurement instrument205asuch as a relative gravimeter similar to the one shown inFIG. 2. The gravimeter inFIG. 2is a weight on a spring, and by measuring the amount by which the weight stretches the spring, local gravity may be measured. From the direction of the gravitational forces on the location device103bone may calculate an angle106between the vector directions from which a location of the device103bmay be derived.

The embodiment ofFIG. 3is a cross-sectional diagram of a drill bit200b, comprising a location device103cin communication with a database201b. In some embodiments the database201bmay be located uphole. The drill bit200bcomprises a body202bintermediate a shank203band a working surface204b. The location device103cmay be placed in a housing in the drill bit200bor farther up the tool string. The location device103cmay also be in communication with a timepiece290bthat may indicate the location time of an astrological object, and may be located uphole or downhole. The database201bmay comprise the locations relative to time of an astronomical object.

FIGS. 4-7are orthogonal diagrams of a derrick100battached to a tool string101bincluding another embodiment of a location device103dshown at different times. InFIGS. 4-7the location device103dis stationary relative to the Earth110upon which it is positioned. Another astronomical object102athat may create a vector direction107amay move relative to the location device103d. As the astronomical object102amoves relative to the location device103dit may continue to exert a gravitational force on the location device103d. This gravitational force may be continuously measured by the location device103das the astronomical object102amoves.

FIGS. 4-7shows a vector direction toward the center of the Earth110while the other vector direction generated by the moon moves with the moon throughoutFIGS. 4-7as shown by the progression of vector direction107ato107dand vector direction105ato105d. The location device103dmay be in communication with the database that may record this data. Knowledge of this data is important in downhole applications due to the unpredictability of the location of a drill bit during the drilling process. Knowing the location of the drill bit aids in locating substances such as oil, natural gas, coal methane, hydrocarbons, minerals, or a combination thereof.

Other applications may arise where the location device is placed on astronomical bodies such as the moon. As the location device is stationary relative to the moon the gravitational force of another astronomical object such as the Earth may be measured as it moves relative to the location device, which may be useful for drilling or exploration applications on the moon.

FIG. 8is an orthogonal diagram of another embodiment of a location device103esituated within an underground enclosure, such as a cave. The location device103emay be able to sense the gravitational forces that may create a vector directions105ethrough a formation of the earth110aand vector direction107eto an astronomical body102b.

The formation may be rock, limestone, mud, concrete, or a combination thereof. An angle106eis formed by the two vector directions105e,107eand may be used to locate the device103e.

FIG. 9is an orthogonal diagram of another embodiment of a location device103f. The location device103fmay measure the force of gravity from more than two astronomical objects102c,102d, and110acreating more than two vector directions105f,107f.FIG. 9shows three vector directions105f,107f, and901caused by three astronomical objects. The astronomical objects102c,102d, and110amay be the Earth, the moon, a comet, the sun, stars, or a combination thereof.

FIG. 10is an orthogonal diagram of a location device103gon a mining machine1001. The location device103gmay be placed in or on the mining machine1001. The location device103gmay travel with the mining machine1001and may take periodic or occasional readings while the mining machine1001is stopped to find its location. The location device103gmay be able to sense the gravitational forces of astronomical objects during the mining process creating at least two vector directions105g,107g. An angle106gis formed by at least two vector directions105g,107gwhich may aid in locating the mining machine1001.

FIG. 11is an orthogonal diagram of an airplane1100comprising a location device103h. The location device103hmay be able to sense the gravitational pull and vector direction105h107hof at least astronomical objects102hand another astronomical object (not illustrated). As the plane1100moves the location device103hmay be in communication with a database that comprises the location of an astrological object102h. In such embodiments, the gravity measurement device will take into account the movement of the airplane. Accelerometers, gyroscopes, magnetometers, may be used to take into account the movement of the airplane. In some embodiments, the altitude may also be taken into account.

FIG. 12is an orthogonal diagram of a submergible object1201comprising a location device103i. The location device103imay be able to sense the gravitational force while submerged in a liquid1202of at least astronomical objects102iand another astronomical object (not illustrated). The submergible object1201may be a submarine, a mine, a fish trap, a SCUBA diver, a scientific instrument or combinations thereof. In some embodiments, a depth may be used in conjunction with the gravity measuring device to help determine the location.

FIG. 13is an orthogonal diagram of a person1301possessing a location device103j. The location device103jmay be able to sense the gravitational pull and vector direction105j,107jof at least astronomical object102jand another astronomical object (not illustrated). The location device103jmay be in wireless communication with a database. The database may comprise the location of an astronomical object102jrelative to time. The location device103jmay be in the form of a handheld device.

FIG. 14is a method1400of locating the position of an object. The method1400comprises a step1401providing a gravity measurement instrument at a position within the universe. The method1400further comprises a step1402of knowing a position of at least two astronomical objects which each provide a gravitational force on the gravity measurement device. The method1400further comprises a step1403of measuring a gravitational field of the gravity measurement device. The method1400further comprises a step1404of calculating the position of the gravity measurement instrument from the gravitational field by determining a vector direction of the gravitational force from each astronomical object. In some embodiments, the method may comprise an additional step of including other information, such as information from another gravity measuring device or another sensor, as necessary to determine the location.