4 results about "Liquid meniscus" patented technology

This application relates to the field of micro / nano-scale flow measurement technology, and discloses a liquid flow measurement method and apparatus based on capillary interface optical tracking. The method includes: determining edge point cloud data of the gas-liquid meniscus in a capillary during a target detection period; performing circular fitting and geometric parameter calculation based on the edge point cloud data to obtain contact data of the gas-liquid meniscus; wherein the contact data includes the contact angle and the contact position between the gas-liquid meniscus and the inner wall of the capillary; and performing flow correction processing based on the contact data to determine the corrected volumetric flow rate during the target detection period. Its beneficial effect is that by using circular fitting and geometric parameter calculation to generate contact data including the contact angle and contact position, the deformation state of the meniscus is quantified, effectively eliminating the volume measurement deviation caused by the meniscus cap deformation, and significantly improving the accuracy and reliability of liquid flow measurement under ultra-low flow and dynamic changing conditions.

A laboratory automation apparatus with a liquid volume measurement functionality comprising a working table, a pipettor comprising a pipetting head with an electrode providing a capacitive sensor with a reference electrode. A robotic arm is configured to move the pipetting head above the working table. A processor is operatively coupled to the robotic arm, to the pipettor and to the electrode by an electronic circuit. A capillary is located on the working table having an opening for receiving a target amount of liquid from the pipettor to form an air-liquid meniscus in the capillary. The robotic arm is configured to hover the electrode over the capillary to detect a change in capacitance related to the position of the meniscus, and the processor is configured to calculate the transferred amount of liquid from the position of the meniscus in the capillary.

The invention discloses a method and system for measuring the volume of liquid and meniscus in a transparent container, and the method comprises the steps: collecting meniscus images of a plurality of different circumferential visual angles of a to-be-measured transparent container, and extracting a corresponding meniscus feature parameter group from each meniscus image; splicing the liquid level characteristic parameter group of each meniscus image to form a spliced characteristic parameter sequence; and inputting the splicing characteristic parameter sequence into a preset meniscus volume prediction model to obtain the volume value of the liquid in the transparent container to be measured. According to the invention, prediction is carried out by extracting the meniscus characteristic parameter groups of different visual angles, so that the accuracy of liquid meniscus volume prediction can be greatly improved; and then a high-precision liquid meniscus volume value is adopted to correct an estimated volume value of the liquid in the to-be-detected transparent container, wherein the estimated volume value is output by the preset volume prediction model based on image detection, so that the precision of liquid volume prediction can be greatly improved.

A laboratory automation device with a liquid volume measurement function includes a table, a pipettor including a pipetting head having an electrode that provides a reference electrode for a capacitive sensor. The robotic arm is configured to move the pipette head over the table. The processor is operatively coupled to the robotic arm, the pipettor, and the electrode by electronic circuitry. The capillary tube is located on a table having an opening for receiving a target amount of liquid from the pipettor to form a gas-liquid meniscus in the capillary tube. The robotic arm is configured to hover the electrode over the capillary to detect a change in capacitance associated with a position of the meniscus, and the processor is configured to calculate a transfer amount of the liquid based on the position of the meniscus in the capillary.