Patent Publication Number: US-11022479-B2

Title: Self-calibrating base station for offset measurements

Description:
CROSS-REFERENCE TO PRIOR APPLICATION 
     This is a Continuation of U.S. application Ser. No. 15/969,235, filed May 2, 2018 and claims the benefit of priority under 35 U.S.C. Section 119(e) of U.S. Application Ser. No. 62/626,866, filed Feb. 6, 2018, which are hereby incorporated by reference in their respective entireties. 
    
    
     FIELD OF THE DISCLOSURE 
     The present disclosure relates generally to calibration of storage tanks, and, more particularly, to calibration of storage tanks used to store and measure amounts of petroleum product stored in the tanks. 
     BACKGROUND OF THE DISCLOSURE 
     Storage tanks are commonly used to store various types of petroleum products. The storage tanks can range in volume capacity from a few thousand cubic meters to hundreds of thousands (or more) of cubic meters. Since the storage capacity of such tanks is known before hand, the tanks are frequently used to measure the amount of petroleum product held in the tanks. However, the volume capacity of such tanks does not remain fixed, but changes with the amount of product placed in the tanks, as well as other factors that affect volume capacity, such as, for example, tank geometry, material used for the walls of the tanks, ambient temperature, and ambient pressure, among other things. Therefore, it is common practice to calibrate storage tanks in order to determine accurate volumetric capacity and, resultantly, accurately determine the amount of petroleum product (e.g., oil or gas) in the tanks. 
     There exist a number of methods of calibrating or measuring the volume of large storage tanks. For instance, one known method is to fill a tank and then measure the amount of liquid drained from the tank. This method, however, is very time consuming, and can be very costly for large size tanks. Normally, this method is avoided unless the tank volume cannot be determined geometrically through physical measurement of the tank parameters. 
     Another method for calibrating tanks is called the optical reference line method (ORLM). The ORLM provides for the calibration of cylindrical tanks by measurement of one reference circumference, followed by determining the remaining circumferences at different elevation levels on the tank. The remaining circumferences are determined by measuring the horizontal offset of the tank wall from a vertical optical reference line. These circumferences are corrected, based on wall thickness, to calculate true internal circumferences, which can then be added to determine the tank volume. 
     An example of an ORLM method is shown in  FIG. 1 , in which there is shown a tank  2 , a magnetic trolley  4 , an optical device  6 , and a horizontal graduated scale  8  attached to the trolley  4 . During operation, the optical device  6  produces an optical ray beam  10  upwardly and parallel to the tank wall  12 . The magnetic trolley  4  is typically controlled by an operator  11  positioned on top of the tank  2 , who holds a rope  13  attached to the trolley  4 . The operator  11  pulls or releases the rope  13  to move the trolley  4  up or down along the tank wall  12 . 
     In order to determine volume, a reference circumference C is initially measured along the perimeter of the tank  2 . The reference circumference C is measured using a measuring tape (not shown), and is typically measured near the bottom of the tank  2 . With the reference circumference C known, the trolley  4  can be raised or lowered by the rope  13  to various vertical stations V along the tank wall  12 . In most systems, the vertical stations V are located between the weld seams on the tank  2 . In  FIG. 1 , two of the vertical stations are indicated by lines V. At each vertical station V, the horizontal offset between the tank wall  12  and the optical ray beam is noted using the horizontal graduated scale  8 . 
     Once a series of measurements have been taken at the vertical stations V, the measurements are repeated with the optical device  6  rotated 180-degrees to verify accuracy. Thereafter, the measurements are used to determine the circumference of the tank at each vertical station V (using the reference circumference as a reference point), and the volume of the tank  2 . Additional factors can also be considered when calculating volume, such as, for example, the temperature of the tank walls  12 . This temperature is typically derived based on the temperature inside the tank and the ambient temperature. 
     While the ORLM method shown in  FIG. 1  is better in some ways than filling the tank  2  and measuring the fluid drained from the tank  2  to determine volume, as discussed above, it has significant drawbacks. For example, measuring the horizontal offset of the trolley  4  from the optical ray beam  10  at only a few select vertical stations V provides relatively few data points from which tank circumferences can be measured. Although this data can be extrapolated to estimate the volume of the tank  2 , such extrapolations tend to be inaccurate. Additionally, the ORLM method shown in  FIG. 1  requires the operator  11  to be positioned on the top of the tank, which can be dangerous. Furthermore, the use of the optical ray beam  10  and a horizontal graduated scale  8  to measure the horizontal offset of the tank wall  12  lacks the precision necessary to calculate accurate tank volumes. This is because an operator must read the horizontal graduated scale  8  at each horizontal offset, often from a distance. 
     To overcome drawbacks related to the operator having to read the horizontal graduated scale  8  at each horizontal offset, it is known to replace the horizontal graduated scale  8  on the trolley  4  with a linear position sensor that accurately senses the location where the optical ray beam  10  impinges on the linear position sensor, and, thereby, facilitates accurate determination of the circumference of the tank wall  12  at the measurement location (e.g., vertical station V). Such linear position sensors, however, fail to sense the optical ray beams  10  where significant drift occurs between the optical device  6  and the trolley  4 , such as, for example, due to irregularities or deformations in the tank wall  12 . When this happens, horizontal offset measurements cannot be made at such measurement locations, and the inaccuracies introduced into the volumetric capacity calculations by the missing measurements can be great enough to render the ORLM calibration method unreliable. 
     There exists an unfulfilled need for an apparatus, a system and a method that provides self-calibration for offset measurements and that overcomes the disadvantages of known systems. 
     SUMMARY OF THE DISCLOSURE 
     According to an aspect of the disclosure, a self-calibrating system is provided that comprises: a mechanism that adjusts a level of a platform; a light-emitting device with beam-like optics (laser, diode, etc.) mounted to the platform; a mechanism for adjusting alignment of the light-emitting device with respect to the platform; a mechanism for rotating the platform by variable angles, including by 180-degrees; and one or more level sensors (such as, for example, spirit levels, tilt sensors, or other devices) that provide feedback on the alignment of the platform normal to the gravity vector. 
     The level sensor may be mounted perfectly parallel with the surface of the platform. 
     The mechanisms for adjusting level, alignment, or rotation can be actuated. The actuation can be accomplished through motors, electroactive materials, magnetics, or other forms of force producing devices and/or systems including gearing, etc. 
     The base station can have a microcontroller to read information from the onboard sensors (or other sources of information) and potentially process adjustments if the base station is actuated. Rather than actuating the base station completely, by recording tilt or misalignment of the optics, the data could be mathematically corrected/compensated rather than actively/physically moving (correcting) the base station alignment. This could simplify the mechanical system. 
     The base station can have a means of communicating with an intelligent sensor that is receiving the reference beam in order to gain additional information for adjusting alignment of the light or platform. The communication can be wireless or wired. 
     The base station can have a means of communicating with the operator control/monitoring device through wired or wireless means. 
     The base station and/or sensor can mount to a surface using magnetics. The base station could mount/rest on the surface being measured (e.g., tank wall) or another surface (e.g., floor/ground). Magnetics are optional. 
     The base station and/or sensor can be actuated to move along the surface being inspected/measured. 
     The base station can have multiple light emitting devices and interface with multiple sensors simultaneously. 
     The sensors and/or base station can report information back to the operator. 
     The base station can have GPS or some other form of localization sensor to record the absolute/geological coordinates of measurement. 
     The base station can emit a complete 360 degree “plane” in a horizontal or vertical direction that could be received by multiple sensors simultaneously. This may be useful for calibrating the offsets of the floor of a tank, or other larger surfaces that need to be level. 
     The sensors can include a type of localization technology in order to capture their relative positions. 
     According to another aspect of the disclosure, a self-calibration method is provided that aligns a base station with a sensor, wherein the method comprises: placing the base station on a surface; ensuring that the base station platform is level with respect to gravity (technically, there are at least two meanings to this—it can be pointed vertically or horizontally, but gravity is the reference that it uses); placing the sensor on another surface at some distance and directly above/in front (in the path of the light emitting device) of the base station; rotating the platform of the device; ensuring that the levelness of the platform is retained and, if not, adjust the platform to split the difference in this error and repeat the earlier step(s) (this might occur if the sensor is not mounted perfectly parallel to the platform); ensuring (by way of communicating with the sensing device) that the position at which the light hits the sensor does not change with rotation; and, adjusting the alignment of the light emitting device by halving the change until the platform can be rotated without the light changing location on the sensor (repeating foregoing steps). 
     The entire process of aligning the base station and sensor could be automated to various degrees. Placement of the sensor device can also be automated. 
     Using a well-known and calibrated device at a known distance, the alignment can be verified by measuring the width of the dot or line as it hits the sensing device. If it is larger than it ought to be, it may mean that there is an angular misalignment between the plane containing the sensor and the direction the light is being emitted. This could arise from errors in the base station alignment or via the sensor itself not being parallel with the ground (normal to gravity vector). 
     The sensor could be actuated to ensure that the thinnest reference beam line is always maintained via rotation of the sensor with respect to the surface it is resting on/attached to (thereby overcoming potential misalignment caused by the sensor). This can be aided by tilt sensors, accelerometers, or other sensors on the sensor board. 
     Alternatively, if the error is coming from misalignment of the base station, the base station can utilize this information in attempting to align itself, possibly using multiple sensors which all have the potential for some error to choose the alignment setting that minimizes the error proportional to the accuracy and reliability of the available inputs. 
     The sensor could be actively actuated in one or two degrees of freedom (roll &amp; pitch) to ensure that is level with respect to gravity. A tilt sensor, accelerometers or an inertial measurement unit could be used as feedback to implement the active leveling. 
     The light emitting device can emit a line or a cross (as seen on the surface it is hitting), with at least one line being parallel to the surface. The other being vertical with respect to the surface. 
     The placement of the sensor device could occur automatically if it is actuated to move along the surface and is already on the desired surface by using some means of detecting its location relative to the base station and moving into a desired position above said base station. 
     The primary mode of motion can be vertical, i.e. in line with the laser such that the sensor/vehicle captures multiple readings as it moves up the surface. 
     This could be coupled to movement that the base station performs in order to move to a new location or rotate on the surface. For example, if the base station moves to the right by a specific distance, the sensing device could receive a command to do likewise until it detected the light and/or accomplished the desired movement. 
     This could be part of a pre-programmed set of instructions for performing a series of measurements that is repeated. 
     These repeated measurements could be modifiable to adjust to different specific cases, such as the number of stations for a given sized tank, along with the distances need to move between each station, etc. 
     If the sensing device has multiple sensors at different distances, alignment of the light source with respect to these can be accomplished by noting differences in where the light is hitting each sensor and adjusting either the sensor or base station to ensure that the light hits each of these sensors at the same location (assuming that they are all offset from the surface by the same amount). Determining whether to adjust the sensors orientation or the base station orientation would require analysis of additional data. 
     The system could utilize an external tracking system to track the location of the sensor/vehicle in 3D space. The tracking system can include, for example, a lidar-based tracker, or the like. This may provide a location tag for every offset measurement in 3D space, which could aid the analysis of the data, as well as the alignment of the base station and vehicle. 
     The system could have more than one light emitting source (laser, diode, etc.). They could be setup in various configurations are needed for the application. For example: two parallel laser lines can be used to acquire more information from the sensing device. 
     A system could have a temperature sensor or other environmental sensors to assist in calibration/compensation of the system due to environmental conditions. 
     Additional features, advantages, and embodiments of the disclosure may be set forth or apparent from consideration of the detailed description, drawings and attachment. Moreover, it is to be understood that the foregoing summary of the disclosure and the following detailed description, drawings and attachment are exemplary and intended to provide further explanation without limiting the scope of the disclosure as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the disclosure, are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the detailed description serve to explain the principles of the disclosure. No attempt is made to show structural details of the disclosure in more detail than may be necessary for a fundamental understanding of the disclosure and the various ways in which it may be practiced. In the drawings: 
         FIG. 1  shows an example of a known system for carrying out the optical reference line method of tank calibration; 
         FIG. 2  shows a tank calibration system according to an embodiment of the instant disclosure; 
         FIG. 3  shows a base station according to an embodiment of the disclosure; 
         FIG. 4  shows a base station computer according to an embodiment of the disclosure; 
         FIGS. 5 and 6  show perspective views of another embodiment of the base station according to principles of the disclosure, with  FIG. 6  showing a partially cut-away view of the base station of  FIG. 5 ; and 
         FIG. 7  shows a process for setting up and operating a base station according to an embodiment of the disclosure. 
     
    
    
     The present disclosure is further described in the detailed description that follows. 
     DETAILED DESCRIPTION OF THE DISCLOSURE 
     The disclosure and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments and examples that are described and/or illustrated in the accompanying drawings and detailed in the following description. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale, and features of one embodiment can be employed with other embodiments as the skilled artisan would recognize, even if not explicitly stated herein. Descriptions of well-known components and processing techniques may be omitted so as to not unnecessarily obscure the embodiments of the disclosure. The examples used herein are intended merely to facilitate an understanding of ways in which the disclosure may be practiced and to further enable those of skill in the art to practice the embodiments of the disclosure. Accordingly, the examples and embodiments herein should not be construed as limiting the scope of the disclosure. Moreover, it is noted that like reference numerals represent similar parts throughout the several views of the drawings. 
       FIG. 2  shows a schematic representation of a tank calibration system  100 , according to a non-limiting embodiment of the instant disclosure. The tank calibration (or “TC”) system  100  measures the volumetric capacity of a tank that includes a tank  102 , a trolley  104 , and a base station  200 . 
     The trolley  104  includes a position sensor  108  that senses a reference beam  110  generated by the base station  200 . The trolley  104  can include an elevation sensor  116  and/or a temperature sensor  118 . The trolley  104  can include a trolley computer  113 . The elevation sensor  116  can sense and determine the distance between the position sensor  108  and ground. The temperature sensor  118  can sense and determine the temperature proximate the tank wall  112 . The trolley computer  113  can be configured to control all operations of the trolley  104 , which can include a robot (not shown), including controlling and operating components of the trolley  104 , including driving and navigating the trolley  104  with respect to the tank wall  102 , and controlling all communication between the trolley  104  and base station  200 , including transmitting and receiving sensor signals, data signals, and control signals over one or more communication links between the trolley  104  and base station  200 . 
     The trolley  104  can be magnetic, motorized, remote controlled, robotic, self-driving and navigating, or autonomous. Where the trolley  104  is magnetic, the magnetism of the trolley  104  can allow it to remain engaged with the tank wall  112 , which can be made of steel or other ferrous material, throughout the process of measuring the contour of the tank wall  112 . This ability to remain engaged with the tank wall  112  throughout the measuring process ensures that the horizontal distance measurements between the trolley  104  and the reference beam  110  are accurate. 
     Embodiments of the invention can be used with tanks made of non-ferrous materials, such as, for example, plastics (e.g., high density polyethylene (HDPE)) or fiberglass. In such applications, the trolley  104  can be equipped with suction cups (not shown) or other tank-attachment mechanisms (not shown) without departing from the scope or spirit of the instant disclosure. Alternatively, the trolley  104  can include the trolley  4  shown in  FIG. 1 . 
     The position sensor  108  can comprise, for example, a linear sensor, a two-dimensional (2D) array sensor, a three-dimensional (3D) array sensor having two or more sensory planes, or the like. The position sensor  108  can include a charge-coupled device (CCD), a solid-state device, a complementary metal-oxide-semiconductor (CMOS) sensor, an electro-optical sensor, an infra-red sensor, a light emitting diode (LED) sensor, a photodetector, a photodiode, a phototransistor, and the like. The position sensor  108  can include an intelligent sensor having a computer (not shown) that includes a computer-executable artificial intelligence (AI) platform which implements a program configured to process information from the sensors and output position information usable to identify the location of the trolley  104 , its orientation, or both location and orientation. As will be appreciated, a given position sensor  108  can include one or all of the foregoing, and any computer can be embedded in the sensor or can comprise the trolley computer  113 , connectable to one or more sensors in a conventional manner. 
     The base station  200  generates and emits the reference beam  110 , which can be oriented substantially parallel to the gravity vector GV and/or the tank wall  112 , as seen in  FIG. 2 . The base station  200  can be affixed to the tank wall  112  (as seen in  FIG. 2 ) or mounted to a support (e.g., tripod shown in  FIG. 1 ). 
     The base station  200  includes a beam source  210  (shown in  FIGS. 3 and 5-6 ) that generates and emits the reference beam  110 . To measure the volumetric capacity of the tank  102 , the circumference of the tank  102  can initially be measured at a predetermined reference location using any appropriate method, including the known methods described above, or using the trolley  104 . For example, in  FIG. 2 , the reference circumference can be determined by measuring the horizontal distance around the circumference of the tank  102  along a line C close to ground. This part of the tank  102  can expand noticeably over time. As per American Petroleum Industry (API) guidelines, by measuring this location, you can recognize an approximate expansion in the tank  102  exceeding a given level, indicating the need for recalibration of the entire tank  102 . This location can be measured before each run (or on a semi-regular basis) to provide the reference circumference for the ORLM method. The tank fill level needs to be the same in measurement of this line and measurement from this line at a later point, but it could be that the tank is emptied and re-filled in between—this depends on the accuracy aimed for. The reference circumference C can provide a substantially constant value for the duration of the time it takes to test, assuming that the fluid inside the tank  102  is not changed. Using the measured reference circumference C value at the reference location, the ring radius (or circumference) of the tank  102  at the reference location can be determined using, for example, the series of equations specified in API MPMS Chapter 2.2A Appendix B to correct for the necessary adjustments to the simple geometric relationship of r=c/2π, where r is the radius, and c is the circumference of the tank  102 . 
     The base station  200  can emit the reference beam  110  vertically, substantially parallel with gravity (i.e., the gravity vector GV). In some embodiments, the distance from the tank wall  112  to the reference beam  110  can be sensed and determined by the position sensor  108  (or the trolley computer  113  or the base station computer  300 ). Alternatively (and/or additionally), height can be determined using encoders on the vehicle wheels (or trolley  104  wheels). Because the ring radius of the tank  102  at the reference location is known, and the distance from the tank wall  112  to the reference beam  110  is known, the distance from the center  114  of the tank  102  to the reference beam  110  can be calculated. Deducting the thickness of the tank wall  112 , the internal tank radius can be determined. 
     The tank calibration system  100  can be designed similar to the system  100  described in commonly-owned U.S. Pat. No. 9,188,472, titled “Enhanced Reference Line Tank Calibration Method and Apparatus,” issued Nov. 17, 2015, the entirety of which is hereby incorporated herein by reference. 
     In measuring an offset in the tank  102  wall circumference, it is critical that the beam source  210  be optically aligned with the position sensor  108 . A slight angular discrepancy between the optical axis of the reference beam  110  and a sensing surface (not shown) of the position sensor  108  can result in significant errors in high accuracy measurements that might be performed over significant distances. Additionally, small changes in material dimensions in the beam source  210  (or the components that hold the beam source  210 ) due to, for example, ambient conditions (such as, e.g., temperature, wind, pressure, humidity, etc.) can cause misalignment between the optical axis and, therefore, the reference beam  110  and the position sensor  108 . Aligning the beam source  210  with respect to the position sensor  108  without the benefit of the instant disclosure would be time consuming, expensive, and could result in damage to the components of these systems if not done properly. In some instances, due to constantly changing conditions, it can be virtually impossible to accomplish by hand. Moreover, without the benefits provided by the instant disclosure, it can be very difficult to keep the beam source  210  aligned with the position sensor  108  in harsh field conditions. The instant disclosure provides a self-calibrating apparatus, system, and method that provide consistently accurate calibration of alignment of the beam source  210 , the reference beam  110 , and the position sensor  108 . 
       FIG. 3  shows an embodiment of the base station  200  constructed according to the principles of the disclosure. The base station  200  comprises a base  201 , a platform  2010 , a base level sensor  220 , a beam level sensor  230 , a beam support base  240 , a beam leveling base  250 , and the beam source  210 . The beam support base  240  and beam leveling base  250  can be formed as a single device or as two or more devices coupled to each other. 
     The base  201  can include a leg  202  that can be adjustable to adjust the space between a first surface (e.g., back surface) of the base  201  that faces the tank wall  112  and the outer surface of the tank wall  112 . The base  201  can be mounted to a robot (not shown), which can attach to and travel along the tank wall  112 , in which case the adjustable leg  202  can adjust the space (or distance) between the first surface of the base  201  and a surface on the robot (not shown). 
     The base  201  can include a plurality of legs  202  (e.g., three legs). One or more of the plurality of legs can be adjustable (as described above) with respect to the surface of the tank wall  112  or the surface of the robot (not shown). The leg(s)  202  can be adjusted so as to align the base  201  in all three dimensions (e.g., x-, y-, and z-axis in the Cartesian coordinate system or r, θ, and φ in the spherical coordinate system) with respect to the gravity vector GV and/or the tank wall  112 , such that the base  201  is substantially parallel to the gravity vector GV. In the embodiment shown in  FIG. 3 , where the platform  2010  is substantially perpendicular to the base  201 , the leg(s)  202  can be adjusted such that the platform  2010  (or its longitudinal axis PLA) is substantially normal (or perpendicular) to the gravity vector GV (shown in  FIG. 2 ). Each leg  202  can include an actuator (not shown), which can extend, retract or secure the leg  202  in position with respect to the base  201 . It is noted that the platform  2010  does not have to be perpendicular to the base  201 , but rather can be configured such that its longitudinal axis PLA forms any angle between 0° and 180° with respect to the longitudinal axis BLA of the base  201 . 
     The base station  200  can include a base station computer  300  (shown in  FIG. 4 ). The base station computer  300  can be affixed to the base  201  or the platform  2010  or located remotely. The leg actuator(s) (not shown) can be connected to a leg actuator driver  330  in the base station computer  300 , which receives position signals (e.g., an x-coordinate signal, a y-coordinate signal, and/or a z-coordinate signal) relative to the gravity vector from the base level sensor  220  via leveling base sensor interface  340  and sends actuator control signals from the leg actuator driver  330  to the leg(s)  202  to adjust the leg(s), and thereby adjust the base  201  and/or platform  2010  into alignment. The level sensor  220  can be configured to detect a real-world level position (x, y, z or r, θ, φ) of the platform  2010  with respect to the gravity vector GV and transmits real-time position signals to the base station computer  300  via the leveling base sensor interface  340 . 
     The leg(s)  202  can be made of a durable lightweight material such as, for example, metal, aluminum, carbon fiber, plastic, and/or the like. The leg(s)  202  can be configured to be adjustable by means of a leg adjuster  2021  (shown in  FIGS. 4 and 5 ). The leg adjuster  2021  can include a knob, a handle, or any other device that is capable of controllably extending, retracting or locking the leg(s)  202  with regard to the base  201 , so as to properly position and align the base  201  with respect to the tank wall (or robot). The leg(s)  202  can be configured to tilt the base  201  by, for example, about +/−1° for each 6.6 mm of travel. Other leg-travel to base-tilt ratios are contemplated herein, including tilting the base  201  with respect to the tank wall by less or more than 1° based on travel of less or more than 6.6 mm of the leg  202 . 
     The base  201  can include one or more handles  203 , which can be made of the same or a different material than the leg(s)  202 . The handle(s)  203  can be designed to be easily grasped by each hand of the operator, allowing the operator to carry, maneuver and position the base  201  at a desired location on or proximate to a tank wall  112  or robot (not shown) that may travel along the tank wall  112 . 
     The base  201  can be configured to be rotated about the axis normal to a surface of the tank wall  112  where the base  201  is to be attached, and/or the gravity vector. The base  201  can include a rotational actuator (not shown) that can rotate the base  201  about the axis TNA (shown in  FIG. 2 ) that is normal to the surface of the mounting site of the tank wall  112  and/or the gravity vector GV (shown in  FIG. 2 ). The actuator can rotate the base  201  between 0° and 180°. The actuator can further rotate the base  201  between 180° and 360°. The actuator (not shown) can be communicatively coupled to the computer  300  (shown in  FIG. 4 ), which can drive the actuator (not shown) to align the base  201  and/or the platform  2010  based on the position signals received from the base level sensor  220 , which can be received via the platform sensor interface  320  (shown in  FIG. 4 ). 
     The base  201  can include a rotational actuator (not shown) that is configured to rotate the platform  2010  about the normal axis NBLA of the base  201 —that is, the axis that is perpendicular to the longitudinal axis of the base  201  (shown in  FIG. 3 ). The actuator can rotate the platform  2010  between about 0° and about 180° with respect to the base  201 . The actuator can further rotate the platform  2010  between 180° and 360°. The platform actuator (not shown) can be communicatively coupled to the computer  300  (shown in  FIG. 4 ), which can drive the platform actuator (not shown) to align the platform  2010  based on the position signals received from the base level sensor  220  via the platform sensor interface  320  (shown in  FIG. 4 ). It is noted that the platform  2010  can be configured to pivot between about 0° and about 180° with respect to the base  201 . The base station  200  can be configured such that the platform  2010  is collapsible with respect to the base  201 , so that the base station  200  may be collapsed for packing or transport. 
     The base  201  can include a permanent magnet  204  that secures the base  201  to the metal tank wall  112  or robot (not shown) by means of magnetic force. The base  201  can include a further magnet  205  that further secures the base  201  to the metal tank wall  112  or robot (not shown). The magnet  205  can include an electromagnet that selectively applies a magnetic field to secure the magnet  205  to the tank wall  112  or robot (not shown). The permanent magnet  204  can serve to affix the base  201  to the tank wall  112  (or robot) and temporarily hold the base  201  in position. The magnet  205  can serve to secure the base  201  to the tank wall  112  (or robot), thereby preventing any movement of the base  201  in a plane parallel to the surface plane of the tank wall  112  (or robot), while permitting adjustment of the space (or distance) between the first surface (e.g., back surface) of the base  201  and outer surface of the tank wall  112  (or robot) by means of the leg(s)  202 . 
     The magnet  205  can comprise an electromagnet, a “switchable magnet” (e.g., a permanent magnet having a magnetic flux that can be short-circuited, thus preventing magnetic attraction to the surface), or the like. The magnet  205  can be turned ON/OFF or adjusted by operation of a magnet actuator  2051  (shown in  FIG. 4 ), which can include a handle that can be grasped and manipulated by the operator. The magnetic field generated by the magnet  205  can be turned ON/OFF or adjusted in intensity by operation of the actuator  2051 . The magnet  205  can be powered by a power source  270  (shown in  FIG. 6 ), which can include an electrical power store such as a battery. 
     The magnet  205  can be communicatively coupled to the computer  300  (e.g., via an input/output (I/O) interface  316  shown in  FIG. 4 ), which can control the magnet  205  to automatically turn ON/OFF or adjust the magnetic field generated by the magnet  205 . 
     In lieu of or in addition to the magnet  204  and/or magnet  205 , the base station  200  can be positioned on a movable platform (not shown), such as, for example, a robot, a trolley, a vehicle, a stand, a tripod, and the like. 
     The platform  2010  can be rigidly or movably (e.g., rotationally) affixed to the base  201 . Alternatively, the platform  2010  can be integrally formed with the base  201  as a single piece. The beam source  210  can be mounted to the platform  2010  by means of the beam leveling base  250  and/or beam support base  240  to allow for adjustment of alignment of the beam source  210  with respect to the platform  2010 . The base level sensor  220  can be attached to or integrally formed with the platform  2010 . Alternatively, the base level sensor  220  can be attached to or integrally formed with the base  201 . The beam level sensor  230  can be attached to or integrally formed with the beam leveling base  250 . Alternatively, the beam level sensor  230  can be attached to the beam support base  240 . 
     The beam source  210  can include a solid-state laser, a gas laser, an excimer laser, a dye laser, a semiconductor laser (e.g., a laser diode), or any device that emits a detectable reference beam  110  that can be detected by the position sensor  108  to determine the position of the base station  200  with respect to the position sensor  108 . The beam source  210  can include, for example, a 635 nm Class Ma laser module with a +/−1.5° fan and a +/−1° steering module. The beam source  210  can be communicatively coupled to a beam source driver  350  in the base station computer  300  (shown in  FIG. 4 ), which can turn ON/OFF or adjust the beam intensity, beam angle, beam spread, and the like, of the reference beam  110 . 
     The beam source  210  can emit a single reference beam  110  as a line or a plurality of beams (e.g., a cross), including, for example, at least one beam parallel to the surface of the tank wall  112  and at least one beam perpendicular to the surface of the tank wall  112 . In the case where the beam source  210  emits a plurality of beams, the beams may be setup in various configurations as needed for a given application. For example, two parallel beams can be used to acquire more information from the position sensor  108 . 
     The base level sensor  220  can comprise a three-dimensional (3D or 3-axis) sensor, such as, for example, a spirit vial level, a circular spirit vial level, a spirit level bubble vial, a tilt sensor, a gyroscope, a geomagnetic sensor, a 3-axis accelerometer, or any other device that is capable of providing feedback on the alignment of the platform  2010  in the plane normal to the gravity vector GV in 3D. The base level sensor  220  can be mounted to or formed parallel with the surface of the platform  2010 . For instance, the base level sensor  220  can be mounted to a surface of the platform  2010  (e.g., via a magnet (not shown)) or formed integrally with the platform  2010  structure. 
     The base level sensor  220  can be communicatively coupled to the base station computer  300  via the platform sensor interface  320  to provide sensed position signals to the base station computer  300 . 
     The beam level sensor  230  can comprise a 3D sensor (similar to beam level sensor  220 ) or one or more two-dimensional (2D) level sensors. The beam level sensor  230  can comprise a dual-axis spirit level, a tilt sensor, or any other device that is capable of providing feedback on the alignment of the normal of the support base  240  (or leveling base  250 ) to the gravity vector. The sensor  230  can provide 4 arcsec sensitivity. The beam level sensor  230  can be actively actuated in one or two degrees of freedom (roll and pitch) to ensure that it is level with respect to gravity. 
     The beam level sensor  230  can be communicatively coupled to the processor base station computer  300  via the leveling base sensor interface  340  to provide sensed position signals to the base station computer  300 . 
     The beam leveling base  250  and beam support base  240  can be integrally formed as a single unit or assembled from a plurality of components. The beam support base  240  can be configured to securely and/or fixedly hold the beam source  210  in position with respect to the beam support base  240 . The beam support base  240  can be configured to securely and/or fixedly hold the beam level sensor(s)  230  in position with respect to the beam support base  240 . The beam support base  240  can be mechanically and/or electrically coupled to the beam leveling base  250 . 
     The beam leveling base  250  can be configured to be adjustable in both the x-y plane and the z-y plane of the real-world coordinate system (x, y, z coordinate system) with respect to the platform  2010 . The beam leveling base  250  can include, for example, a dual-axis leveling base that can be manually controlled by an operator or electronically by the base station computer  300  (shown in  FIG. 4 ). The beam leveling base  250  can have a range of movement of about +/−2.5° and 2 arcsec sensitivity. 
     The beam leveling base  250  can be configured to be adjustable in all three-dimensions (x-, y-, z-dimension or r-, θ-, φ-dimension), including rotational adjustment with respect to the platform  2010 . The beam leveling base  250  can be arranged to rotate from 0° to 180° about the longitudinal axis PLA of the platform  2010 . 
     The beam leveling base  250  can include a plurality (e.g., two) of adjustable knobs  2501 ,  2502  (shown in  FIG. 5 ) to adjust the normal plane of the beam leveling base  250  with respect to the gravity vector GV (shown in  FIG. 3 ). For instance, the knobs  2501 ,  2502  can be adjusted to center the beam level sensor(s)  230  (e.g., by bringing the bubbles in the spirit vials to the centers of each of the 2D sensors  2301  and  2302 , in  FIG. 5 ). 
       FIG. 4  shows an embodiment of the base station computer  300 , constructed according to the principles of the disclosure. The base station computer  300  is configured to implement the various aspects of the disclosure. The base station computer  300  includes a controller  310 , the platform sensor interface  320 , the leg actuator driver  330 , the leveling base sensor interface  340 , the leveling base driver  350 , a position sensor interface  360 , and beam source driver  370 , all of which can be communicatively coupled to a bus  305 . The system bus  305  can be any of several types of bus structures that can further interconnect to a memory bus (with or without a memory controller), a peripheral bus, and a local bus using any of a variety of commercially available bus architectures. 
     The controller  310  includes a processor  311 . The processor  311  can be any of various commercially available processors. Dual microprocessors and other multi-processor architectures can also be employed as the processor  311 . 
     The controller  310  includes a computer-readable medium that can hold executable or interpretable computer code (or instructions) that, when executed by the processor  311 , causes the steps, processes and methods described herein to be carried out. The computer-readable medium can be provided in a storage  312 , HDD  313 , and/or ODD  314 . The computer readable medium can include sections of computer code that, when executed by the processor  311 , cause the base station  200  to carry out each of the Steps shown in  FIG. 7 , as well as all other process steps described or contemplated herein. 
     The storage  312  includes a read only memory (ROM)  312 A and a random access memory (RAM)  312 B. A basic input/output system (BIOS) can be stored in the non-volatile memory  312 A, which can include, for example, a ROM, an EPROM, an EEPROM, or the like. The BIOS can contain the basic routines that help to transfer information between elements within the controller  310  and, more generally, the base station computer  300  such as during start-up. The RAM  312 B can include a high-speed RAM such as static RAM for caching data. 
     The controller  310  can include an internal hard disk drive (HDD)  313 , such as, for example, an enhanced integrated drive electronics (EIDE) drive, a serial advanced technology attachments (SATA) drive, or the like, and an optical disk drive (ODD)  314  (e.g., for reading a CD-ROM disk (not shown), or, to read from or write to other high capacity optical media such as the DVD). The HDD  313  can be configured for external use in a suitable chassis (not shown). The HDD  313  and ODD  314  can be connected to the system bus  305  by a hard disk drive interface (not shown) and an optical drive interface (not shown), respectively. The hard disk drive interface (not shown) can include a Universal Serial Bus (USB) (not shown), an IEEE 1394 interface (not shown), and the like, for external applications. 
     The HDD  313  and/or ODD  314 , and their associated computer-readable media, can provide nonvolatile storage of data, data structures, computer-executable instructions, and the like. The HDD  313  and/or ODD  314  can accommodate the storage of any data in a suitable digital format. The storage  312 , HDD  313 , and/or ODD  314  can include one or more apps that are used to execute aspects of the architecture described herein. 
     A number of program modules can be stored in the HDD  313 , ODD  314 , and/or RAM  312 B, including an operating system (not shown), one or more application programs (not shown), one or more application programming interfaces (APIs), other program modules (not shown), and program data (not shown). Any (or all) of the operating system, application programs, APIs, program modules, and program data can be cached in the RAM  312 B as executable sections of computer code. 
     The controller  310  can include a network interface  315 . The network interface  315  can be connected to the network (not shown). The network interface  315  can include a wired or a wireless communication network interface (not shown) and/or a modem (not shown). When used in a local area network (LAN), the base station computer  300  can be connected to the LAN network through the wired and/or wireless communication network interface; and, when used in a wide area network (WAN), the base station computer  300  can be connected to the WAN network through the modem. The network (not shown) can include a LAN, a WAN, or the like. The modem (not shown) can be internal or external and wired or wireless. The modem can be connected to the system bus  305  via, for example, a serial port interface (not shown). 
     The controller  310  can include the input/output (I/O) interface  316 . The controller  310  can receive commands and data from an operator via the I/O interface  316 , which can be communicatively coupled to one or more input/output devices, including, for example, a keyboard (not shown), a mouse (not shown), a pointer (not shown), a microphone (not shown), a speaker (not shown), a display (not shown), and/or the like. The received command and data can be forward to the processor  311  from the I/O interface  316  as instruction and data signals via the bus  305 . 
     The platform sensor interface  320  can be connected to the system bus  305  and the base level sensor  220  (shown in  FIG. 3 ) by means of a communication link. The platform sensor interface  320  can be configured to receive sensor signals from the base level sensor  220 , which can indicate the position of the base level sensor  220  in the x-, y-, z-coordinate system (or r, θ, and φ spherical coordinate system) with respect to the gravity vector GV. The position sensor signals can be received in real-time. 
     The leg actuator driver  330  can be connected to the system bus  305  and the leg actuator(s) (not shown) by means of a communication link. The leg actuator driver  330  can be configured to communicate with and drive each leg actuator (not shown) to thereby align the base  201  and/or platform  2010  based on the position signals received from the base level sensor  220  via the platform sensor interface  320 . 
     The leveling base sensor interface  340  can be connected to the system bus  305  and the beam level sensor  230  (shown in  FIG. 3 ) by means of a communication link. The leveling base sensor interface  340  can be configured to receive position signals from the beam level sensor  230 , which can indicate the position of the beam level sensor  230  in the x, y, z-coordinate system (or r, θ, and φ spherical coordinate system) with respect to the gravity vector GV. The sensor position signals can be received in real-time. 
     The leveling base driver  350  can be connected to the system bus  305  and the beam leveling base  250  (shown in  FIG. 3 ) by means of a communication link. The leveling base driver  350  can be configured to communicate with and drive the beam leveling base  250  to thereby move and align the beam source  210  (and/or beam  110 ) based on the sensor position signals received from the beam level sensor  230  via the leveling base sensor interface  340 . 
     The position sensor interface  360  can be connected to the system bus  305  and the position sensor  108  (shown in  FIG. 2 ) by means of a communication link. The position sensor interface  360  can be configured to receive sensor position signals from the position sensor  108 , which can indicate the position of the beam  110  with respect to the position sensor  108  in the x, y, z-coordinate system (or r, θ, and φ spherical coordinate system). The sensor position signals can be received in real-time. 
     The beam source driver  370  can be connected to the system bus  305  and the beam source  210  by means of a communication link. The beam source driver  370  can be configured to communicate with and drive the beam source  210  to thereby power, turn ON/OFF or adjust the beam  110 , including adjustment of beam intensity, beam angle, beam spread, and the like. 
     Rather than actuating the base station  200  completely, by recording tilt or misalignment of the beam source  210  optical components (not shown), the base station computer  300  can mathematically correct and/or compensate the data received from the various sensors and components in the base station  200 , instead of (or in addition to) actively/physically moving (correcting) the physical components of the base station  200 . This implementation can be used to simplify the mechanical system of the base station  200 . 
     The placement of the position sensor  108  can be controlled by the base station computer  300 . The placement of the position sensor  108  can occur automatically if it is actuated to move along the surface of the tank wall  112  and is already on the desired surface. The location of the position sensor  108  relative to the base station  200  can be detected and driven to move into a desired position above the base station  200 . For example, if the base station  200  moves to the right (or left) by a specific distance, the base station computer  300  can transmit a command signal to the trolley  104  and/or position sensor  108  to do likewise until it is detected that the position sensor  108  is aligned with the base station  200 . In this regard, alignment can be determined based on the location of the reference beam  110  with respect the position sensor  108 . 
     The base station computer  300  can be pre-programmed with a set of instructions or computer code to perform a series of measurements, which can be repeated. The repeated measurements could be modifiable to adjust to different specific cases, such as the number of vertical stations V for a given size tank, along with the distances need to move between each station, and the like. 
     Furthermore, the base station computer  300  can be configured to drive the trolley  104  and/or position sensor  108  and/or the base station  200 , so as to cause any or all of them to move with respect to the tank wall  112  being measured. 
     The base station computer  300  can include a global positioning satellite (GPS) receiver or some other form of localization sensor (such as, for example, using triangulation of WiFi transceivers) to record the absolute/geological coordinates of measurement. 
     Any one or more of the sensors  108 ,  220 , and  230  can include a GPS receiver or some other form of localization sensor (such as, for example, using triangulation of WiFi transceivers) to record the absolute/geological coordinates of the sensor(s) and/or in order to capture their relative positions. 
     The base station  200  can be configured to emit a complete 360-degree “plane” in a horizontal or vertical direction that could be received by multiple sensors (not shown) simultaneously. This configuration can be useful for calibrating offsets of the floor of a tank, or other larger surfaces that need to be level. 
     If the position sensor  108  includes a plurality of sensors positioned at different distances, alignment of the reference beam  110  with respect to these can be accomplished by noting differences in where the reference beam  110  is hitting each position sensor  108  and adjusting either the position sensor(s)  108  or base station  200  to ensure that the reference beam(s)  110  hits (or impinges) each of these position sensors  108  at the same location (assuming that they are all offset from the surface by the same amount). Determining whether to adjust the position sensor  108  orientation or the base station  200  orientation can include analysis of additional data. 
     The calibration system of the base station  200  and position sensor  108  can include an external tracking system (not shown) to track the location of the position sensor  108  and/or base station  200  in 3D space. For instance, the system can include a lidar-based tracker (not shown) or the like. In this regard, the system can provide a location tag for every offset measurement in 3D space, which could aid the analysis of the data, as well as the alignment of the base station  200  (and carrying vehicle (not shown)). 
       FIGS. 5 and 6  show perspective views of another embodiment of the base station  200 , constructed according to the principles of the disclosure.  FIG. 6  shows a partially cut-away view of the base station  200  of  FIG. 5 . 
     Referring to  FIGS. 5 and 6 , the base station  200  comprises a base  201 , a beam source  210 , a three-dimension (3D) base level sensor  220 , a plurality (e.g., two) two-dimensional (2D) beam level sensors  2301 ,  2302  (or  230  collectively), a beam support base  240 , a beam leveling base  250 , a beam source driver  260 , and a power source  270 . 
     The beam source  210  has a beam emitting end  2105  that can be coupled to or integrally formed with a miniature rotary stage  2108  that can be adjusted by an adjustable knob  2109  to adjust (e.g., angle and/or spread) or steer the reference beam  110 . The rotary stage  2108  can be adapted for about 2 arcsec sensitivity laser beam steering. The beam source  210  can be coupled to the beam source driver  260  by means of an IP67 or similar connector. 
     The base  201  includes a plurality of legs  202  (e.g., three legs), a pair of handles  203 , a permanent magnet  204 , and a controllable magnet  205  that can be controlled by operation of a magnet actuator  2051 . In this embodiment, only one of the legs  202  is adjustable. 
     The leg(s)  202  can be made of a durable lightweight material such as, for example, metal, aluminum, plastic, carbon fiber, or the like. The leg(s)  202  can be adjustable by means of a leg adjuster  2021 . The leg adjuster  2021  can include a knob, a handle, or any other device that is capable of controllably extending or retracting the leg(s)  202  with regard to the base  201 , so as to properly position and align the base  201  with respect to the tank wall. The leg(s)  202  can be configured to tilt the base  201  by +/−1° for each 6.6 mm of travel. Other leg travel to base tilt ratios are contemplated herein, including tilting the base  201  with respect to the tank wall  112  by less or more than 1° based on travel of less or more than 6.6 mm by the leg  202 . 
     The handle(s)  203  can be made of the same or a different durable lightweight material than the leg(s)  202 . The handles  203  are designed to be easily grasped by each hand of the operator, allowing the operator to carry, maneuver and position the base  201  to a desired location on or proximate to a tank wall  112 , or a robot (not shown) that can travel along the tank wall  112 . 
     The permanent magnet  204  can include a permanent magnet that exerts, for example, about 44 Kgf max force and/or about 17 Kgf effective force. The permanent magnet can exert max forces greater (or less than) 44 Kgf and effective forces greater (or less than) 17 Kgf. 
     The controllable magnet  205  can include an electromagnet, which can be controlled by operation of the magnet actuator  2051 . The magnet  205  can be turned ON/OFF or its magnetic field adjusted by operation of the magnet actuator  2051 , which can include a handle that can be grasped and manipulated by the operator. The magnetic field generated by the magnet  205  can be turned ON/OFF or adjusted by operation of the actuator  2051 . The magnet  205  can be powered by the power source  270 , which can include an electrical power store such as a battery (e.g., LiFePO4, 6.4V, 9.6 Wh battery). The magnet  205  can include an electromagnet that generates, for example, about 75 Kgf max force and/or about 24 Kgf effective force. The magnet  205  can exert max forces greater (or less than) 75 Kgf and effective forces greater (or less than) 24 Kgf. 
     The 3D (or 3-axis) base level sensor  220  can comprise, for example, a spirit vial level, a circular spirit vial level, a spirit level bubble vial, a tilt sensor, or any other device that is capable of providing feedback on the alignment of the base  201  in the plane normal to the gravity vector. 
     The 2D beam level sensors  230  can comprise a dual-axis spirit level, a tilt sensor, or any other device that is capable of providing feedback on the alignment of the base  201  normal to the gravity vector. The sensors  230  can provide 4 arcsec sensitivity. 
     The beam support base  240  can be mechanically coupled to the beam leveling base  250  and hold the 2D level sensors  230  and the beam source driver  260 . The beam leveling base  250  can include a dual-axis leveling base with a range of about +/−2.5° and 2 arcsec sensitivity. The beam leveling base  250  can include a plurality (e.g., two) of adjustable knobs  2501 ,  2502  to adjust the normal plane of the beam leveling base  250  with respect to the gravity vector. For instance, the knobs  2501 ,  2502  can be adjusted to center the 2D beam level sensors  230  (e.g., by bringing the bubbles in the spirit vials to the centers of each of the 2D sensors  2301  and  2302 ). 
       FIG. 7  shows a process  400  for setting up and operating the base station  200  (shown in  FIGS. 5-6 ) according to an embodiment of the disclosure. As noted previously, the base station computer  300  (shown in  FIG. 4 ) can comprise sections of computer code (or instructions) to carry the Steps shown in  FIG. 7 . 
     Referring to  FIGS. 5-7 , initially, after making sure the magnet  205  is switched OFF (or disengaged), the handles  203  can be grasped by the operator and the base station  200  positioned at a desired position on or proximate to a tank wall of a tank to be measured (Step  405 ). The base station  200  should be positioned with the base level sensor  220  facing upward. The base station  200  can then be affixed to a surface of the tank wall  112  by the magnet  204 . The magnet  205  should still be disengaged. 
     Keeping one hand on the base station  200  and not yet engaging the magnet  205 , the base level sensor  220  can be checked to make sure the base station  200  is properly aligned with respect to the gravity vector (Step  410 ) and, if necessary (NO at Step  412 ), the base station  200  can be adjusted (Step  415 ) until the base station  200  is in proper alignment (YES at Step  412 ) with respect to the gravity vector GV. In the case of the embodiment shown in  FIGS. 5 and 6 , the base level sensor  220  can be visually inspected to make sure the bubble in the circular spirit vial is within a predetermined base level range, such as, for example, about 2.5° from zero (Steps  410 ,  412 ). If not (NO at Step  412 ), then using the handles  203  and/or leg adjuster  2021  the base station  200  can be adjusted (Step  415 ) to bring the bubble in the spirit vial  220  within the predetermined base level range, for example, about 2.5° from zero (Step  410 ). 
     Once it is determined, based on the base level sensor  220 , that the base station  200  is properly aligned with respect to the gravity vector GV (YES at Step  412 ), then magnet  205  can be engaged by, for example, operation of the magnet actuator  2051  to secure the base station  200  to the tank wall  112  (Step  420 ). After the magnet  205  is engaged (e.g., by turning the magnet actuator  2051  by, for example, about 180°), the operator can release the both handles  203 . 
     After confirming that the base level sensor  220  indicates proper alignment of the base  201  with respect to the gravity vector GV (YES at Step  412 ), the beam level sensors  230  ( 2301  and  2302 ) can be checked (Step  425 ) and, if necessary (NO at Step  428 ), the leveling base  250  can be adjusted (Step  430 ) until the beam level sensors  230  indicate proper alignment of the leveling base  250  (YES at Step  428 ) (and, therefore, the beam source  210 ) with respect to the gravity vector GV. In the case of the embodiment in  FIGS. 5 and 6 , the dual-axis spirit vials  2301  and  2302  can be visually inspected to make sure the bubbles in the vials are within a predetermined beam level range, such as, for example, about 2.5° from zero (Steps  425 ,  428 ). If not (NO at Step  428 ), then using the knobs  2501  and  2502  the beam leveling base  250  can be adjusted (Step  430 ) to bring the bubbles in the spirit vials  2301  and  2302  within the predetermined beam level range, for example, about 2.5° from zero (Steps  425 ,  428 ). 
     The beam level sensor  230  indications can then be recorded (Step  435 ) (for example, by recording the bubbles in the spirit vials  2301  and  2302 ) and the leveling base  250  can be rotated 180° from the first position shown in  FIG. 3  to a second, opposite position (not shown) (Step  440 ). The platform  2010  and beam leveling base  250  can include a rotation locking mechanism (not shown), which can comprise a female receptacle (not shown) on one of the platform  2010  and the beam leveling base  250 , such as, for example, a pin hole that receives a male protrusion (not shown) on the other of the platform  2010  and the beam leveling base  250 , such as, for example, a pin, ball bearing, or the like, so as to releasably lock the beam leveling base  250  into one or more predetermined positions radially with respect to the platform  2010 , including a position where the normal to the surface of the beam leveling base  250  (or a plane substantially parallel to the reference beam  110 ) is 180° offset radially from the normal of the top surface of the platform  2010 . 
     After the beam leveling base  250  is rotated 180° from its first position (Step  440 ), the beam level sensor(s)  230  can be checked to make sure the beam leveling base  250  is properly aligned with respect to the gravity vector GV (Step  445 ) and, if it is determined that it is not (NO at Step  448 ), then the beam leveling base  250  can be adjusted (Step  450 ) until the beam level sensors  230  indicate proper alignment with respect to the gravity vector GV (YES at Step  448 ). In the case of the embodiment in  FIGS. 5 and 6 , the knobs  2501  and  2502  can be manipulated (Step  450 ) to adjust the leveling base  250  to bring the bubbles in the spirit vials  2301  and  2302  within a predetermined beam level range, such as, for example, about 2.5° from zero (Steps  445 ,  448 ). Each knob  2501 ,  2502  can be adjusted (Step  450 ) to cut the distance traveled by each spirit vial bubble in half. Optionally, a set screw (not shown) can be provided on each knob  2501 ,  2502 , so as to lock the knobs  2501 ,  2502  in place. 
     A reading of the position sensor  108  (shown in  FIG. 2 ) can be captured and recorded (Step  455 ). As noted earlier, the position sensor  108  can be provided on a trolley  104  and the location of the trolley  104  can be recorded instead or in addition to the position sensor  108  reading. Then, the beam leveling base  250  can be rotated 180° back to its first position (Step  460 ). As the beam leveling base  250  is rotated back to its first (or original) position, the beam level sensors  230  should remain relatively static. The beam level sensors  230  should be checked to make certain the beam leveling base  250  is properly aligned with respect to the gravity vector GV (Step  465 ). In the case of the embodiment in  FIGS. 5 and 6 , the bubbles in the spirit vials  2301 ,  2302  should not move by more than a predetermined rotated beam level range, such as, for example, about ½ of a graduation mark (Step  465 ). If the bubbles move by more than the predetermined rotated beam level range amount, for example, ½ of a graduation mark (NO at Step  468 ), then Steps  435  to  465  should be repeated. 
     If the bubbles do not move by more than the predetermined rotated beam level range amount (YES at Step  468 ), then the new reading of the position sensor  108  (and/or the trolley) should be captured and recorded (Step  470 ). 
     After the base level sensor  220  (YES at Step  420 ) and the beam level sensor  230  (YES at Steps  428 ,  448  and  468 ) are confirmed to indicate proper alignment of the platform  2010  and the beam leveling base  250  with respect to the gravity vector GV, the position sensor  108  signal can be checked (Steps  475 ,  480 ) and the rotary stage  2108  can be adjusted (Step  485 ) (e.g., by adjusting the knob  2109 ) to steer the beam fan of the reference beam  110  until the position sensor  108  (and/or trolley  104 ) reading is within a predetermined beam position range (Step  480 ), such as, for example, as close as possible to an average of the two (2) previously recorded readings (YES at Step  480 ), at which point the position sensor reading can be recorded (Step  490 ). The beam leveling base  250  can be (optionally) rotated 180° one or more times to further validate the beam level sensors  230  remain static (e.g., the spirit level bubbles in sensors  2301 ,  2302  remain fixed throughout the rotation), and the position sensor  108  (and/or trolley  104 ) match before and after each rotation. 
     A DigiPas DWL-8500xy, for example, can be optionally mounted on top of the beam leveling base  250  and used to verify its level throughout the 180° rotation(s). 
     An “actuator,” as used in this disclosure, means a machine, device, circuit, component, module, or any system of machines, devices, circuits, components, modules, or the like, which are capable of producing a mechanical force, such as, for example, without limitation, a motor, an electrical motor, a hydraulic actuator, a pneumatic actuator, a gear, rack-and-pinion, a magnet, an electroactive material, or the like. 
     A “communication(s) link,” as used in this disclosure, means a wired and/or wireless medium that conveys data or information between at least two points. The wired or wireless medium can include, for example, a metallic conductor link, a radio frequency (RF) communication link, an Infrared (IR) communication link, an optical communication link, or the like, without limitation. The RF communication link can include, for example, WiFi, WiMAX, IEEE 802.11, DECT, 0G, 1G, 2G, 3G, 4G or 5G cellular standards, Bluetooth, or the like. A communication(s) link can include a public switched telephone network (PSTN) line, a voice-over-Internet-Protocol (VoIP) line, a cellular network link, an Internet protocol link, or the like. The Internet protocol can include an application layer (e.g., BGP, DHCP, DNS, FTP, HTTP, IMAP, LDAP, MGCP, NNTP, NTP, POP, ONC/RPC, RTP, RTSP, RIP, SIP, SMTP, SNMP, SSH, Telnet, TLS/SSL, XMPP, or the like), a transport layer (e.g., TCP, UDP, DCCP, SCTP, RSVP, or the like), an Internet layer (e.g., IPv4, IPv6, ICMP, ICMPv6, ECN, IGMP, IPsec, or the like), and a link layer (e.g., ARP, NDP, OSPF, Tunnels (L2TP), PPP, MAC (Ethernet, DSL, ISDN, FDDI, or the like), or the like). 
     A “network,” as used in this disclosure means, but is not limited to, for example, at least one of a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), a personal area network (PAN), a campus area network, a corporate area network, a global area network (GAN), a broadband area network (BAN), a cellular network, the Internet, or the like, or any combination of the foregoing, any of which can be configured to communicate data via a wireless and/or a wired communication medium. These networks can run a variety of protocols not limited to TCP/IP, IRC or HTTP. 
     A “computer,” as used in this disclosure, means any machine, device, circuit, component, or module, or any system of machines, devices, circuits, components, modules, or the like, which are capable of manipulating data according to one or more instructions, such as, for example, without limitation, a processor, a microprocessor, a central processing unit, a general purpose computer, a super computer, a personal computer, a laptop computer, a palmtop computer, a notebook computer, a desktop computer, a workstation computer, a server, a server farm, a computer cloud, or the like, or an array of processors, microprocessors, central processing units, general purpose computers, super computers, personal computers, laptop computers, palmtop computers, notebook computers, desktop computers, workstation computers, servers, server farms, computer clouds, or the like. 
     The terms “including,” “comprising” and variations thereof, as used in this disclosure, mean “including, but not limited to,” unless expressly specified otherwise. 
     The terms “a,” “an,” and “the,” as used in this disclosure, means “one or more,” unless expressly specified otherwise. 
     Devices that are in communication with each other need not be in continuous communication with each other, unless expressly specified otherwise. In addition, devices that are in communication with each other can communicate directly or indirectly through one or more intermediaries. 
     Although process steps, method steps, algorithms, or the like, can be described in a sequential order, such processes, methods and algorithms can be configured to work in alternate orders. In other words, any sequence or order of steps that can be described does not necessarily indicate a requirement that the steps be performed in that order. The steps of the processes, methods or algorithms described herein can be performed in any order practical. Further, some steps can be performed simultaneously. 
     When a single device or article is described herein, it will be readily apparent that more than one device or article can be used in place of a single device or article. Similarly, where more than one device or article is described herein, it will be readily apparent that a single device or article can be used in place of the more than one device or article. The functionality or the features of a device can be alternatively embodied by one or more other devices which are not explicitly described as having such functionality or features. 
     A “computer-readable medium,” as used in this disclosure, means any medium that participates in providing data (for example, instructions) which can be read by a computer. Such a medium can take many forms, including non-volatile media, volatile media, and transmission media. Non-volatile media can include, for example, optical or magnetic disks and other persistent memory. Volatile media can include dynamic random access memory (DRAM). Transmission media can include coaxial cables, copper wire and fiber optics, including the wires that comprise a system bus coupled to the processor. Transmission media can include or convey acoustic waves, light waves and electromagnetic emissions, such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, an EPROM, a FLASH-EEPROM, any other memory chip or cartridge, a carrier wave as described hereinafter, or any other medium from which a computer can read. The computer-readable medium can include a “Cloud,” which includes a distribution of files across multiple (e.g., thousands of) memory caches on multiple (e.g., thousands of) computers. 
     Various forms of computer readable media can be involved in carrying sequences of instructions to a computer. For example, sequences of instruction (i) can be delivered from a RAM to a processor, (ii) can be carried over a wireless transmission medium, and/or (iii) can be formatted according to numerous formats, standards or protocols, including, for example, WiFi, WiMAX, IEEE 802.11, DECT, 0G, 1G, 2G, 3G or 4G cellular standards, Bluetooth, or the like. 
     While the disclosure has been described in terms of exemplary embodiments, those skilled in the art will recognize that the disclosure can be practiced with modifications in the spirit and scope of the appended claims. These examples are merely illustrative and are not meant to be an exhaustive list of all possible designs, embodiments, applications, or modifications of the disclosure.