Patent attributes
An apparatus for measuring foot blood flow has a platform with a platform contact surface configured to receive a foot force from a user placing their foot on the contact surface. The apparatus also has a plurality of PPG sets (having at least one light source and at least one detector) extending through the platform contact surface, and a plurality of springs. Each PPG set is coupled with one or more of the springs to movably couple with the platform. In addition, each spring is biased to produce a biasing force via its coupled PPG set when the contact surface of the platform receives the foot. To maintain consistent pressure against the skin and good signal to noise ratio, each PPG set and its corresponding one or more springs are configured so that the biasing force has a magnitude that is substantially independent of the foot force magnitude.
