We demonstrate an application of the mechanically induced long period fiber grating system for a foot plantarmeasurement. The system is designed as a fixed fiber grating platform that can be utilized for monitoring a subject’s footplantar pressure distribution in static and dynamic activities. The pressure information obtained from the foot loadingcharacteristics can be used for various application such as disease diagnosis of foot problem, foot ware design, sportbiomechanics and injury prevention. The system is composed of a strand of a single mode fibers with 800 nm cut offwavelength and circular plastic grooved plates with the grating period of 0.8 and 1.0 mm made by 3 D printing. The sensingunits are fixed at biomechanically significant positions; fore-foot, mid-foot and hind-foot of the foot platform formonitoring the foot plantar pressure distribution. The sensing locations are chosen appropriately to contact with sensitiveareas of foot and can initially provide enough foot plantar pressure characteristics of a subject. The fiber sensing unitswith grating having different periods provides different sets of transmission spectra which separately respond to individualperturbed points. Preliminary result shows that the system can be used to classify different types of foot. With someadvantageous properties of the optical fiber such as structural flexibility and light weight, the system can successfully beused to monitor the static and dynamic perturbations such as the movement of the body center of mass and foot actions inthe stance phase. The study has demonstrated that the proposed fiber-optic sensing systems has a feasibility of being usedas an alternative for insole plantar pressure detection systems.
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