Submersible device for measuring drilling fluid properties

1. A system comprising:

a structure containing a drilling fluid;

a measuring device immersed within the drilling fluid, the measuring device comprising:

a shell defining a chamber;

a weight adapted to cause the measuring device to sink through the drilling fluid, wherein said weight is located in the chamber;

at least one sensor adapted to measure a property of the drilling fluid, wherein the sensor is located in the chamber, and wherein the property includes at least one of location, acceleration, velocity, temperature, pressure and electrical properties;

a predetermined quantity of a ferrimagnetic material contained in the shell; and

a transmitter adapted to transmit data representing the property; and

a processor adapted to:

receive the data from the measuring device immersed in the drilling fluid; and

determine at least one characteristic of the drilling fluid based on the data received, wherein the characteristic includes at least one of viscosity, density and sag; and

a plurality of magnetic devices positioned around the structure such that selective activation of the magnetic devices moves the measuring device through the drilling fluid to different locations within the structure.

2. The system of claim 1 , wherein the shell has a shape selected from egg-shaped or ovoid, spherical, plumb-bob shaped, cylinder, rounded cylinder, cone, rounded cone and parachute-shaped.

3. A system comprising,

a structure containing a drilling fluid;

a plurality of measuring devices immersed within the drilling fluid, wherein each measuring device of the plurality of measuring devices comprises:

a shell defining a chamber;

a weight adapted to cause the measuring device to sink through the drilling fluid, wherein said weight is located in the chamber;

at least one sensor adapted to measure a property of the drilling fluid, wherein the sensor is located in the chamber, and wherein the property includes at least one of location, acceleration, velocity, temperature, pressure and electrical properties; and

a transmitter adapted to transmit data representing the property; and

a processor adapted to:

receive the data from the measuring device immersed in the drilling fluid; and

determine at least one characteristic of the drilling fluid based on the data received, wherein the characteristic includes at least one of viscosity, density and sag; and

wherein each of the measuring devices is configured to measure a property of the drilling fluid different from the other measuring devices, and the shape of the shell for each measuring device is configured to facilitate the measurement of the property, and wherein the processor receives data relating to the property from each of the measuring devices so as to determine a plurality of characteristics of the drilling fluid.

4. The system of claim 3 , wherein at least a portion of the measuring devices include a predetermined quantity of a ferrimagnetic material contained in the shell, and wherein the system includes a plurality of magnetic devices positioned around the structure such that selective activation of the magnetic devices moves the portion of the measuring device through the drilling fluid to different locations within the structure.

5. The system of claim 3 , wherein at least a portion of the measuring device include a motor configured to propel the portion of the measuring devices through the drilling fluid to different locations within the structure.

6. A method comprising:

immersing a measuring device into a drilling fluid in a structure such that said measuring device moves through the drilling fluid by a locomotive configured to propel the measuring device through the fluid, and wherein the measuring device includes a predetermined quantity of a ferrimagnetic material contained in the measuring device, and wherein the locomotive includes a plurality of magnetic devices positioned around the structure such that selective activation of the magnetic devices moves the measuring device through the drilling fluid to different locations within the structure;

detecting a first property of the drilling fluid by a sensor contained in the measuring device to produce first data, wherein the detecting of the first property occurs while the measuring device moves through the drilling fluid in the structure;

receiving the first data from the measuring device; and

determining a first characteristic of the drilling fluid based on the first data received, wherein the first characteristic includes at least one of viscosity, density and sag, and wherein the detecting of the first property occurs at multiple locations throughout the drilling fluid so that the determining of the first characteristic represents changes in the first property of the drilling fluid among different locations.

7. The method of claim 6 further including:

introducing the drilling fluid containing the measuring device downhole into a well;

detecting a second property of the drilling fluid by the sensor contained in the measuring device to produce second data, wherein the detecting of the second property occurs while the measuring device moves with the drilling fluid downhole;

receiving the second data from the measuring device; and

determining a second characteristic of the drilling fluid based on the second data received, wherein the second characteristic includes at least one of temperature, viscosity, density, sag and circulation of the drilling fluid downhole.

8. The method of claim 7 , wherein the detecting of the second property occurs at multiple locations downhole so that the determining of the first characteristic represents changes in the first property of the drilling fluid among different locations downhole.

9. The method of claim 8 , wherein the drilling fluid comprises a plurality of components at a concentration, and the method further comprises:

adjusting the concentration of the components based on the first characteristic.

10. The method of claim 9 , wherein the measuring device includes the locomotive, and the locomotive comprises a motor configured to propel the measuring devices through the drilling fluid to different locations within the structure.

11. The method of claim 10 , wherein the measuring device comprises an outer shell having a shape selected from egg-shaped or ovoid, spherical, plumb-bob shaped, cylinder, rounded cylinder, cone, rounded cone and parachute-shaped.

12. The method of claim 11 , wherein there are a plurality of the measuring devices which together detect a plurality of first properties, and each of the measuring devices is configured so as to detect a different first property of the drilling fluid from the other measuring devices, and wherein the first data relates to the plurality of first properties so as to determine the first characteristic of the drilling fluid.

13. The method of claim 12 , wherein when the drilling fluid is introduced downhole, the plurality of the measuring devices together detect a plurality of second properties, and wherein the second data relates to the plurality of second properties so as to determine the second characteristic of the drilling fluid.

14. The method of claim 13 , wherein the shape of the shell is configured to facilitate the detecting of at least one of the first property and the second property.

15. A method comprising:

immersing a measuring device into a drilling fluid such that said measuring device moves through the drilling fluid;

detecting a first property of the drilling fluid by a sensor contained in the measuring device, wherein the detecting of the first property occurs while the measuring device moves through the drilling fluid, and wherein there are a plurality of the measuring devices which together detect a plurality of first properties, and each of the measuring devices is configured so as to detect a different first property of the drilling fluid from the other measuring devices to produce first data related to the plurality of first properties;

receiving the first data from the plurality of measuring devices; and

determining a first characteristic of the drilling fluid based on the first data received such that the first characteristic is determined from the plurality of first properties, wherein the first characteristic includes at least one of viscosity, density and sag.

16. The method of claim 15 , wherein when the drilling fluid is introduced downhole, the plurality of the measuring devices together detect a plurality of second properties, and wherein the second data relates to the plurality of second properties so as to determine the second characteristic of the drilling fluid.

17. The method of claim 16 , wherein the shape of the shell is configured to facilitate the detecting of at least one of the first property and the second property.