Fume Hood Sash Position Sensing With Reflective Marker Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current systems for determining the position of fume hood sashes are difficult to install and calibrate, affecting their reliability, cost, and robustness.
Innovation Solution
A system using an emitter and sensor panel with reflective markers and an image sensor to determine the distance between markers on opposite edges of the sash opening, allowing for easy installation and calibration by calculating the sash opening area based on the distance between marker images.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If complex sensor structures (conductive strips, light emitters/detectors, string potentiometers) are used to detect sash position, then measurement precision is improved, but device complexity and difficulty of installation increase
Solution Approach 1:
The patent replaces complex mechanical sensor structures (conductive strips, light emitters/detectors, string potentiometers) with a simple optical system consisting of a camera and reflective markers. The camera captures images of markers attached to the sash, and image processing algorithms calculate sash position based on marker coordinates, eliminating the need for complex mechanical mounting structures and calibration mechanisms.
Solution Approach 2:
The patent uses reflective markers that create optical copies (reflections) of light from the environment. The camera captures these reflected light patterns as images, which are then processed to determine sash position. This optical copying approach replaces direct mechanical or electrical sensing, simplifying the overall system while maintaining measurement precision.
2Measurement precision
If complex sensor structures with mounting requirements are used, then measurement precision is improved, but ease of operation and installation are worsened
Solution Approach 1:
The patent replaces mechanical mounting structures and calibration mechanisms with a vision-based system. Reflective markers are attached to the sash using simple adhesives, and the camera captures images to determine position. This eliminates complex mechanical assembly and calibration procedures, dramatically improving ease of installation while maintaining measurement precision through image processing algorithms.
Solution Approach 2:
The system uses naturally available light sources in the environment to illuminate the reflective markers, eliminating the need for separate illumination systems. The camera automatically captures images and the processing algorithm independently calculates sash position from marker coordinates, making the system self-sufficient and easy to deploy without complex setup procedures.
3Measurement precision
If multiple sensors are positioned at strategic locations to determine sash position, then measurement precision is improved, but device complexity and cost increase
Solution Approach 1:
The patent uses a single camera to perform multiple functions: capturing images of reflective markers, determining sash position, and calculating opening area. This single optical device replaces multiple specialized sensors (conductive strips, light emitters/detectors, or string potentiometers), reducing system complexity, component count, and overall cost while maintaining measurement precision through versatile image processing algorithms.
Solution Approach 2:
The patent combines the functions of illumination, detection, and measurement into a single vision-based system. The camera integrates the detection capabilities of multiple sensors, while reflective markers serve as both targets and measurement references. Image processing algorithms merge marker coordinate information to calculate both sash position and opening area, consolidating multiple measurement functions into one system.
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 solution simplifies the installation and calibration process, enhancing the reliability and cost-effectiveness of sash position detection, thereby improving the overall performance of fume hood ventilation control.
Implementation Method 1
A first reflective marker is mounted on one edge of the sash opening to reflect light from at least the first light emitter
Data Source
AI summary
Systems and methods for determining the area of a sash opening in a fume hood formed by at least one movable sash panel. An emitter and sensor panel is mounted in a fume hood enclosure space. The emitter and sensor panel comprises at least one light emitter mounted on one side of an optical sensor. The at least one light emitter is configured to illuminate the fume hood enclosure space. At least one reflective marker is mounted on one edge of the sash opening to reflect light from the at least one light emitter. Optical information detected at the optical sensor is used to determine a variable distance to the at least one reflective marker. The variable distance and known distance parameters are used to determine the area of the sash opening.