US 11,815,523 B2
Multi-point filtering liquid level detection methods and apparatus
William D. Dunfee, Newark, DE (US); Mark H. Sprenkle, Newark, DE (US); and Colin Ingersoll, Wilmington, DE (US)
Assigned to Siemens Healthcare Diagnostics Inc., Tarrytown, NY (US)
Appl. No. 18/248,127
Filed by Siemens Healthcare Diagnostics Inc., Tarrytown, NY (US)
PCT Filed Oct. 6, 2021, PCT No. PCT/US2021/053851
§ 371(c)(1), (2) Date Apr. 6, 2023,
PCT Pub. No. WO2022/076616, PCT Pub. Date Apr. 14, 2022.
Claims priority of provisional application 63/088,934, filed on Oct. 7, 2020.
Prior Publication US 2023/0273231 A1, Aug. 31, 2023
Int. Cl. G01N 35/10 (2006.01); G01N 35/00 (2006.01)
CPC G01N 35/1009 (2013.01) [G01N 35/0099 (2013.01); G01N 35/1002 (2013.01); G01N 2035/1025 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A method of detecting a level of a liquid in a well, comprising:
looking up in a memory an expected liquid level of the liquid in the well;
ramping a probe into the well containing the liquid to a well depth;
measuring and recording a measured liquid level of the liquid from the ramping; and
calculating a next expected liquid level at least in part based on multi-point filtering and adjusting a depth of insertion of the probe into the well based on the next expected liquid level, wherein the next expected liquid level is used as the detected level of liquid in the well, further wherein the multi-point filtering comprises subtracting the expected liquid level from the measured liquid level to obtain a current normalized measured liquid level, calculating a current normalized filtered liquid level using an average filter, median filter, or mode filter on previous normalized measured liquid levels and the current normalized measured liquid level, and de-normalizing the current normalized filtered liquid level by adding the current normalized filtered liquid level to the expected liquid level to obtain the next expected liquid level.