DO Probe Curved Sensing Surface to Reduce Bubble Measurement Artifacts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dissolved oxygen (DO) probes in bioprocess systems experience measurement artifacts due to gas bubbles adhering to the sensing surface, leading to inaccurate oxygen readings and oscillating oxygen supply, which can stress or kill cells in bioreactors.
Innovation Solution
The solution involves modifying the sensing surface of DO probes with 3D shapes and processor instructions to prevent bubble adherence and implementing algorithms to filter out measurement artifacts caused by bubbles, ensuring accurate oxygen readings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If gas bubbles are added to the sample to maintain optimal oxygen levels, then the oxygen supply is improved, but measurement artifacts are generated due to bubble adhesion on the sensing surface
Solution Approach 1:
The sensing surface is designed with a curved or domed shape instead of a flat surface. This curvature causes gas bubbles to roll off the sensing surface due to gravity and surface tension, preventing bubble adhesion that would otherwise cause measurement artifacts. The curved geometry maintains oxygen sensing functionality while eliminating the harmful effect of bubble accumulation.
Solution Approach 2:
The sensing surface employs an asymmetric tilted orientation rather than a symmetric horizontal placement. This asymmetric angle causes bubbles to naturally slide off the sensing surface along the tilt, preventing them from adhering to the measurement area. The asymmetric design allows continuous oxygen measurement without interference from bubble-induced artifacts.
2Measurement precision
If bubbles adhere to the sensing surface, then oxygen concentration in bubbles is measured, but this leads to erroneous oxygen supply control
Solution Approach 1:
The curved sensing surface design ensures that bubbles cannot stablely adhere to the measurement area. Bubbles contact the curved surface and roll off due to gravitational and surface tension forces, preventing the situation where bubble oxygen concentration would be erroneously measured and lead to incorrect control decisions.
Solution Approach 2:
The invention extracts or removes bubbles from the measurement process by designing the sensing surface to actively shed bubbles. This separation of bubbles from the sensing area ensures that only dissolved oxygen in the liquid sample is measured, not oxygen within adhering bubbles, thereby maintaining reliable control.
3Object-affected harmful factors
If the sensing surface is modified with 3D shapes, then bubble adherence is reduced, but device complexity increases
Solution Approach 1:
The sensing surface is formed as a simple curved or domed structure that can be manufactured as a single integrated component. This geometric modification, while changing the surface topology, does not require complex multi-component assemblies or sophisticated manufacturing processes, thus limiting the increase in device complexity.
Solution Approach 2:
The bubble-reducing geometric feature is merged with the sensing surface itself rather than being a separate附加 component. The curved sensing surface serves dual functions: oxygen detection and bubble shedding, eliminating the need for additional bubble removal mechanisms and minimizing overall device complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces measurement artifacts, stabilizes oxygen supply, and maintains optimal oxygen levels in bioreactors, enhancing cell health and bioprocess efficiency.
Implementation Method 1
The separation membrane is angled with respect to the axis of the probe for avoiding, by buoyancy, the adhesion of bubbles
Data Source
Figure 1A~1D
Figure 2
Figure 3~5B
AI summary
Methods and apparatus for reducing measurement artifacts of sensor measurements are disclosed herein. An aspect of the invention includes a measurement device configured to reduce measurement inaccuracies in a sample. The measurement device comprises a measurement probe comprising a sensor configured to detect a characteristic of the sample and generate a measurement signal based thereon. The measurement device further comprises a memory configured to store instructions for applying a filter to the measurement signal. The measurement device also further comprises a filtering module configured to process the instructions for applying the filter to the measurement signal to generate a filtered output with reduced measurement inaccuracies.