The basic idea of the arch index program is to calculate the ratio of the middle third area of a footprint to the whole footprint area. How we obtain and process the foot pressure image directly and severely determines the result. I recently upgraded my arch index program on the image capture module. In the last version, it captures a certain frame of the pressure heatmap and applies arch index calculation on the frame. The frame is independent of its adjacent frames and only represents the pressure information at the very moment.
However, if we wanted to use our floor mat to replace Harris mat, we need to have the pressure image captured in the same way as the footprint captured from Harris mat. With Harris mat, ink will leave on all the area that any pressure ever applied to, even if the foot just stays on Harris mat for a few seconds/milliseconds. You can consider the footprint from Harris mat as an accumulated image of a few frames.
In the upgraded version, we capture the frames in a duration of time and accumulate the largest area that pressure can ever reach in the duration. The results of static arch index detection were pretty impressive. According to a comparison with the result of the last version on a few testers so far, their arch index values increased significantly on the static arch index, especially when the testees have a high arch. Data collection just started, will update when we get enough results.