A sensor system includes a vessel and a sensor apparatus. The vessel holds a fluid having a predetermined density and at least partly immerses at least one three-dimensional object having a predetermined buoyancy. The sensor apparatus senses a three-dimensional form of the three-dimensional object while at least partly immersed in the fluid and provides a data model representative of the sensed three-dimensional form at least partly immersed in the fluid. The predetermined density of the fluid renders the three-dimensional object substantially buoyancy-neutral.

A sensor system includes a vessel and a sensor apparatus. The vessel holds a fluid having a predetermined density and at least partly immerses at least one three-dimensional object having a predetermined buoyancy. The sensor apparatus senses a three-dimensional form of the three-dimensional object while at least partly immersed in the fluid and provides a data model representative of the sensed three-dimensional form at least partly immersed in the fluid. The predetermined density of the fluid renders the three-dimensional object substantially buoyancy-neutral.

A sample to be measured is placed in a medium solution between two circular magnets to ensure that the sample to be measured is levitated in a set circular area between the two circular magnets, and a levitation position of the sample to be measured in the magnetic field is measured. The density of the sample is calculated according to formula (I):

[00001]${}_s={}_m+\frac{{}_m-{}_s}{g_0}\left(B_r\frac{B_z}{r}+B_z\frac{B_z}{z}\right).$

Compared to the prior art, the method of the present disclosure provides a novel method for measuring a density of a substance, in which the involved device is easy to operate and has low cost, and the measurement results are easy to observe and have high accuracy.

A sample to be measured is placed in a medium solution between two circular magnets to ensure that the sample to be measured is levitated in a set circular area between the two circular magnets, and a levitation position of the sample to be measured in the magnetic field is measured. The density of the sample is calculated according to formula (I):

[00001]${}_s={}_m+\frac{{}_m-{}_s}{g_0}\left(B_r\frac{B_z}{r}+B_z\frac{B_z}{z}\right).$

Compared to the prior art, the method of the present disclosure provides a novel method for measuring a density of a substance, in which the involved device is easy to operate and has low cost, and the measurement results are easy to observe and have high accuracy.

Provided is a density sensor, a downhole tool, and a well system. The density sensor, in one aspect, includes one or more float chambers, and two or more floats located within the one or more float chambers. In one aspect, the two or more floats have a density ranging from 0.08 sg to 2.1 sg, and further a first of the two or more floats has a first known density (.sub.1) and a second of the two or more floats has a second known density (.sub.2) greater than the first known density (.sub.1). The density sensor, according to this aspect, may further include one or more sensors located proximate the one or more float chambers, the one or more sensors configured to sense whether ones of the two or more floats sink or float within production fluid having an unknown density (.sub.f).

A specific gravity measurement device has an in-air weight sensor that measures the weight, in air, of an object to be measured, memory that automatically stores the weight in air, an in-liquid weight sensor that measures the weight, in a liquid, of the object to be measured, a memory that automatically stores the weight in the liquid, a measuring device that, on the basis of the weight in air and the weight in a liquid, measures the specific gravity of the object, and an initialization device that automatically initializes the display of the specific gravity of the object, after the object to be measured is retrieved from within the liquid.

A specific gravity measurement device has an in-air weight sensor that measures the weight, in air, of an object to be measured, memory that automatically stores the weight in air, an in-liquid weight sensor that measures the weight, in a liquid, of the object to be measured, a memory that automatically stores the weight in the liquid, a measuring device that, on the basis of the weight in air and the weight in a liquid, measures the specific gravity of the object, and an initialization device that automatically initializes the display of the specific gravity of the object, after the object to be measured is retrieved from within the liquid.

A sample to be measured is placed in a medium solution between two circular magnets to ensure that the sample to be measured is levitated in a set circular area between the two circular magnets, and a levitation position of the sample to be measured in the magnetic field is measured. The density of the sample is calculated according to formula (I): ${?}_s={?}_m+\frac{{?}_m-{?}_s}{g{?}_0}\left(B_r\frac{?B_z}{?r}+B_z\frac{?B_z}{?z}\right).$
Compared to the prior art, the method of the present disclosure provides a novel method for measuring a density of a substance, in which the involved device is easy to operate and has low cost, and the measurement results are easy to observe and have high accuracy.

A sample to be measured is placed in a medium solution between two circular magnets to ensure that the sample to be measured is levitated in a set circular area between the two circular magnets, and a levitation position of the sample to be measured in the magnetic field is measured. The density of the sample is calculated according to formula (I): ${?}_s={?}_m+\frac{{?}_m-{?}_s}{g{?}_0}\left(B_r\frac{?B_z}{?r}+B_z\frac{?B_z}{?z}\right).$
Compared to the prior art, the method of the present disclosure provides a novel method for measuring a density of a substance, in which the involved device is easy to operate and has low cost, and the measurement results are easy to observe and have high accuracy.

A launching tube for use with a liquid filled tank can be sized to accommodate a submersible vehicle for dispensing into the liquid tank. The tank can be an electrical transformer or any other liquid containing tank such as but not limited to a chemical tank. The launching tube can include a valve for insertion into a launching chamber, and a tank side valve for launching of the submersible into the tank. In one form the launching tube includes an antenna for communication with the submersible and/or a base station. The launching tube can also include a sensor such as a camera, as well as an agitator. The agitator can be used to facilitate bubble removal from the inside of the launching tube.