Optical Sensor Calibration Vessel for Low-Volume Accurate Turbidity Setup

Solution Overview

Problem

Existing turbidity sensors require calibration using potentially harmful solutions like formazine or styrene-divinylbenzene, which may not be accurately documented or can be contaminated, and the calibration process is inefficient due to the need for large volumes of solution that cause measurement errors from vessel walls.

Innovation Solution

A calibration vessel with a minimized volume and a guide for precise sensor alignment, integrated reference device for solution monitoring, and features to minimize light interactions with the vessel walls, along with cleaning and circulation systems, ensures accurate and safe calibration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of substance

If the calibration vessel size is reduced to minimize calibration solution volume, then the amount of costly calibration solution required is minimized, but reflection or backscattering on the vessel walls distorts the measured value and this error increases as the distance from the walls decreases

Engineering Contradiction:

Improvecalibration solution volumeVSAvoidturbidity measurement accuracy

Core Design Contradiction:

Loss of substanceVSMeasurement precision

Solution Approach 1:

A guide structure is introduced as an intermediary element between the sensor and the vessel walls. The guide positions the sensor at an optimal distance from the walls, mediating the conflict between minimizing solution volume and maintaining measurement accuracy by preventing wall effects while allowing compact vessel design

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The sensor position parameter is precisely controlled through the guide structure, changing the spatial parameter (distance from walls) to optimize the measurement. This allows the sensor to be positioned at the optimal distance that minimizes both solution volume requirements and wall interference effects

Inventive Principle:

Principle #35Parameter changes

2Productivity

If multiple sensors are calibrated sequentially using the same calibration solution, then efficiency is improved and solution cost is reduced, but the calibration solution becomes contaminated and the known turbidity value is distorted

Engineering Contradiction:

Improvecalibration efficiencyVSAvoidcalibration solution integrity

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The guide structure extracts and isolates the sensor positioning function from the calibration solution environment. By providing a dedicated positioning mechanism, the sensor is precisely placed in the optimal measurement position without contacting or contaminating the calibration solution, enabling repeated use of the same solution for multiple sensor calibrations

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The calibration system performs self-service through the guide structure that automatically positions each sensor correctly upon insertion. This eliminates the need for manual positioning and minimizes contact between the operator and calibration solution, reducing contamination risk while maintaining high calibration throughput

Inventive Principle:

Principle #25Self-service

3Device complexity

If the sensor is manually positioned in the calibration vessel, then the device complexity is reduced, but the alignment and positioning accuracy varies and repeatability is compromised

Engineering Contradiction:

Improvepositioning mechanism complexityVSAvoidsensor alignment precision

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The guide structure incorporates visual indicators (such as colored marks or alignment features) that provide immediate visual feedback when the sensor is correctly positioned. This simple visual system ensures precise and repeatable alignment without requiring complex mechanical positioning mechanisms or electronic controls

Inventive Principle:

Principle #32Color changes

Solution Approach 2:

Instead of making the sensor adjustable to achieve proper positioning, the approach is inverted: the guide structure provides fixed positioning features that the sensor must align with. This reverses the complexity from the sensor side to the vessel side, ensuring precise positioning while keeping the sensor design simple

Inventive Principle:

Principle #13The other way round (Inversion)

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 solution allows multiple sensors to be calibrated efficiently with minimal solution use, reduces measurement errors, and enhances operational safety by minimizing contact with harmful substances.