Differential Fluid Level Sensing Relative to Sample Receptacle Rim
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Automated analytical systems face challenges in accurately measuring fluid levels in sample receptacles due to mechanical tolerance stack uncertainties, leading to potential spilling and cross-contamination, which can result in false positives and inefficient processing.
Innovation Solution
An automated system performs differential measurements by using a sensor to measure distances from both the fluid surface and the receptacle rim, refining measurements through filtering and averaging, to accurately determine the fluid level relative to the rim, thereby preventing spilling and cross-contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If automated systems use standard measurement methods for fluid level, then processing speed is maintained, but measurement precision deteriorates due to mechanical tolerance stack uncertainties
Solution Approach 1:
The patent replaces mechanical measurement methods with optical measurement using a laser sensor. The laser sensor emits light that reflects off the fluid surface and receptacle rim, providing precise measurements without mechanical contact. This substitution eliminates mechanical tolerance stack uncertainties while maintaining system simplicity.
Solution Approach 2:
The patent introduces light as an intermediary medium between the sensor and the measurement targets (fluid surface and receptacle rim). By using light reflection and time-of-flight measurement, the system achieves high precision without direct mechanical interaction, thereby avoiding mechanical tolerance accumulation.
2Productivity
If automated systems handle sample receptacles at high speed, then productivity increases, but fluid spilling increases due to acceleration forces
Solution Approach 1:
The patent performs fluid level measurement before the sample receptacle enters high-speed handling zones. By identifying overfilled receptacles in advance, the system can take preventive actions such as adjusting handling speed, modifying acceleration profiles, or routing to different processing paths, thereby preventing fluid spilling during high-speed operations.
Solution Approach 2:
The patent implements a feedback loop where fluid level measurement data is fed back to the control system, which then adjusts handling parameters in real-time. This closed-loop control enables the system to maintain high productivity while dynamically adapting to prevent fluid spilling based on actual fluid levels.
3Reliability
If automated systems measure fluid level with high precision, then spilling prevention improves, but measurement time increases due to multiple measurements and filtering
Solution Approach 1:
The patent implements continuous or near-continuous scanning of the fluid surface using the laser sensor, taking multiple measurements in rapid succession. By performing measurements continuously during the receptacle's passage through the measurement zone, the system gathers sufficient data for reliable determination without significantly increasing total measurement time.
Solution Approach 2:
The patent uses periodic measurement sampling with filtering to determine the true fluid level. By taking multiple periodic measurements and applying statistical filtering (such as averaging or median calculation), the system achieves high reliability in spilling prevention while keeping the effective measurement time short through efficient data processing.
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
The system reduces measurement uncertainty, ensures accurate fluid level determination, minimizes spilling, and enhances processing efficiency by quarantining overfilled receptacles, thus reducing contamination risks and improving throughput.
Implementation Method 1
a sensor for periodically measuring a distance between the sensor and (i) one or more surfaces of the sample receptacle and (ii) a surface of a fluid contained within the sample receptacle
Data Source
AI summary
Automated systems determine a level of fluid relative to a rim of a sample receptacle defining an open top of the sample receptacle. The systems utilize a distance sensor to measure the distance between the rim of the sample receptacle and the surface of a fluid sample contained in the sample receptacle, where at least one of the sensor and the sample receptacle is moved relative to the other to enable the sensor to obtain a sequence of discrete measurements of distances between the sensor and the rim of the sample receptacle and between the sensor and the surface of the fluid sample. A controller processes an output signal from the sensor to determine a level of the fluid relative to the rim of the sample receptacle. The derivative of the sequence of discrete measurements may be used to identify the rim and the fluid surface in the output signal.