Initial attempts to have foot-force sensors to measure the
pressure applied in the front and rear parts of the foot (ball
and heel of foot) are described in [3]. Their proposed floor
reaction force (FRP) sensor detects air pressure changes
sensed when foot-pressure is applied to their customized
air-pressure force sensors. Up to today the electrical force
sensors instead of air pressure based sensors are widely
applied. For instance, thin film sensors such as flexiforce
(Tekscan
R ) or shunt force sensor (Sensitronics
R ) are ideal
for integration in footwear, as they have small thickness
of less than one millimeter to fit into the limited space
of the footwear. In addition, these types of force sensors
are an inexpensive and lightweight alternative to multi-axis
force/torque sensors.