Four-dimensional analysis system, apparatus, and method

A method for measuring fluid absorption and retention of a personal hygiene article, comprising the steps of:

• obtaining a reference sample of the personal hygiene article;
• obtaining a mass of the reference sample;
• inputting the mass of the reference sample into a computer;
• placing the reference sample adjacent or within a fixture, the fixture comprising a radiotransparent material;
• placing a line proximal to the reference sample such that the line is in fluid communication with the reference sample;
• positioning the reference sample and the fixture proximal to an imaging device such that the imaging device is capable of generating one or more images;
• inputting into the computer a flow rate for a fluid to be pumped through the line, the computer being in communication with a pump operatively connected to a fluid source and to the line;
• inputting into the computer a command to obtain one or more images of the reference sample when the fluid is pumped from the fluid source through the line and to the reference sample, the computer being in communication with the imaging device;
• inputting into the computer a command to commence the pump at the flow rate;
• acquiring one or more images from an imaging device;
• obtaining one or more data sets from the one or more images;
• and
• generating an estimate for a final grayscale value representative of a fluid flow by adding up a volume of each of the one or more data sets;
• wherein a reference value for a fluid flow is provided;
• and
• wherein a grayscale value representative of the reference value for the fluid flow is estimated.