The performance of ultrasound cleaning solution by ‘echovista’ is measured using various image processing techniques. This enables precise and comprehensive contaminant information (such as position, size and velocity) to be measured throughout the cleaning process. Most of the testings are carried out in ‘echovista’ or credited facility organised by ‘echovista’.
De-droplet
The droplet clearing performance of a prototype can be determined by following the procedures detailed in the strategy documents below.
Performance Metrics
A controlled lighting condition highlights the droplet edges present on the glass surface. Using edge detection, the outer contours of each droplet can be located, and therefore the total clean area and droplet size distribution can be calculated. Footage from a droplet cleaning sequence is processed frame by frame to provide a record of this data over time.
The droplet contour data can be used to create other performance metrics:
Our Sensor Performance Metric can give an indication of how obstructed a particular sensor may be given the present contaminant. The glass is divided into a grid with the desired resolution and obstruction threshold. The extent of sensor obstruction is calculated by examining each grid element, and determining whether the level of obstruction is above or below the defined threshold.
Our FOV Performance Metric can be used if particular areas of the glass are of a higher priority for cleaning. A custom contour map with areas of various priority levels allows for a score to be calculated based on the priority and obstruction of each area.
The Camera POV Performance Metric can precisely determine the extent of distortion or obstruction a contaminant has on a camera’s image. Calculating the mean square error (MSE) of each frame (with respect to a clean image) provides a score for the amount of obstruction throughout the cleaning sequence.
De-dirt
The dried dirt cleaning performance of a prototype can be determined by following the procedures detailed in the strategy documents below.
Images of before and after cleaning are processed using a colour threshold to accurately determine the area of contamination.
De-ice
The de-icing performance of a prototype can be determined by following the procedures detailed in the strategy documents below.
Images of before and after cleaning are processed using a colour threshold to accurately determine the area of contamination. The de-icing tests are carried out in a climate chamber.
De-fogging
The de-fogging ability of a prototype can be demonstrated by applying a humidifier to either the inside or outside of the glass. The glass is chilled prior to the fog application to ensure dense coverage.
