System and method for field monitoring of stationary assets

• US 9,711,038 B1
• Filed: 04/19/2013
• Issued: 07/18/2017
• Est. Priority Date: 08/31/2011
• Status: Active Grant

• Current Assignee: Iii, E. Strode Pennebaker
• Original Assignee: Iii, E. Strode Pennebaker
• Inventors: Pennebaker, III, E. Strode
• Primary Examiner(s): Phan, Hai
• Assistant Examiner(s): Balseca, Franklin
• Application Number:
  US13/866,672
• Time in Patent Office: 1,551 Days
• Field of Search: 700 50, 700 54, 700 55
• CPC Class Codes: G01F 23/00 Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
• CPC Class Codes: G01F 23/18 Indicating, recording or alarm devices actuated electrically
• CPC Class Codes: G01F 23/28 by measuring the variations of parameters of electromagnetic or acoustic waves applied directly to the liquid or fluent solid material
• CPC Class Codes: G01F 23/296 Acoustic waves
• CPC Class Codes: G01F 23/2962 Measuring transit time of reflected waves
• CPC Class Codes: G01F 23/804 containing circuits handling parameters other than liquid level
• CPC Class Codes: G01F 25/20 of apparatus for measuring liquid level
• CPC Class Codes: G01N 2291/02836 Flow rate, liquid level
• CPC Class Codes: G01N 29/024 by measuring propagation velocity or propagation time of acoustic waves
• CPC Class Codes: G01N 29/07 by measuring propagation velocity or propagation time of acoustic waves
• CPC Class Codes: G01N 29/14 using acoustic emission techniques echo of particles G01N29/046; measuring mechanical vibrations or acoustic waves in solids in general G01H1/00
• CPC Class Codes: G01N 29/50 using auto-correlation techniques or cross-correlation techniques
• CPC Class Codes: G08C 17/02 using a radio link
• CPC Class Codes: H04Q 2209/40 using a wireless architecture
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A wireless sensor network including a number of wireless modules for monitoring sensors associated with stationary assets. A wireless module includes a wireless transceiver, a processor, a location acquisition unit, configured to acquire a location item identifying a location of the wireless module, and a memory.

Claims

1. A method for determining a fill level of a container, the method comprising:

acquiring first impulse data;

reformatting the acquired first impulse data into a first subset of the acquired first impulse data, the first subset comprising a plurality of subset times, wherein the first subset includes fewer data points than the first impulse data;

acquiring second impulse data;

reformatting the acquired second impulse data into a second subset of the acquired second impulse data, wherein the second subset includes fewer data points than the second impulse data;

computing the fill level based on the first and the second impulse data subsets;

computing a first impulse arrival time based on at least one of the plurality of subset times;

computing a second impulse arrival time based on at least one of the plurality of second subset times; and

computing the fill level based on the first and second impulse arrival times;

wherein computing the second impulse arrival time based on at least one of the plurality of second subset times further comprises;

acquiring, by an acoustic impulse receiver, reference impulse data; and

reformatting the acquired reference impulse data into a reference subset of the acquired reference impulse data, the reference subset comprising a plurality of reference amplitude values that correspond to a plurality of reference times; and

wherein reformatting the acquired second impulse data further comprises;

reformatting the acquired second impulse data so that the second subset includes a plurality of second impulse data amplitude values that correspond to the plurality of second subset times;

determining an offset value by computing a cross-correlation between the second subset and the reference subset;

selecting one of the plurality of second subset times as the impulse arrival time based on the offset value.

2. The method of claim 1, further comprising acquiring the first impulse data by an acoustic impulse generator and acquiring the second impulse data by an acoustic impulse receiver, spatially separated from the acoustic impulse generator;

wherein the acoustic impulse generator further comprises;

an acoustic impulse receiver is located within the acoustic impulse generator.

3. The method of claim 1, further comprising acquiring the first and second impulse data by an acoustic impulse receiver, wherein the first impulse data comprises preflexural wave data and the second impulse data comprises flexural wave data.

4. The method of claim 3, wherein the plurality of first subset times comprise zero-crossing times of the preflexural wave data and the plurality of second subset times comprise zero crossing times of the flexural wave data.

5. The method of claim 1, further comprising acquiring the first and second impulse data by an acoustic impulse receiver, wherein the first impulse data comprises a first portion of a flexural wave data and the second impulse data comprises a second portion of the flexural wave data.

6. The method claim 1, wherein selecting one of the plurality of second subset times further comprises:

shifting the times of the second subset by the offset value; and

selecting one of the plurality of second subset times that corresponds to a time that is within a range that includes the reference time;

setting the second impulse arrival time as equal to a time corresponding to the selected one of the plurality of second subset times of the second subset.