Gait Analysis System

FootSTEPS

(Product ID: FS3F-1)

The FootSTEPS system is a shear stress sensor platform for shear measurements on a human foot during gait. FootSTEPS is an imaged based system, delivering high-resolution images of both shear and pressure across a subjects foot as they walk across the platform. A high-resolution camera images ISSI’s Surface Stress Sensitive Film (S3F) layer, polymerized on a glass window, as participants walk across the aluminum construction FootSTEPS platform. The S3F layer contains a probe material that enables changes in film thickness, produced primarily by pressure, to be visualized as changes in illumination level. The mathematical ratio of loaded and unloaded images quantifies the vertical displacement of the film giving normal pressure data.

To measure shear, a series of markers are applied to the film below the opaque upper layer. These markers are displaced laterally during foot contact, primarily by shear forces. Cross-correlation analysis quantifies the displacements produced by shear.

A force plate, mounted underneath the FootSTEPS platform, simultaneously measures three forces and three moments about the x, y, and z axes. Synchronized data collection is initiated by a trigger pulse from the force plate on initial foot contact. 3-D displacement maps provide rapid visualization of the pressure and shear patterns produced by foot contact. Reconstruction of the pressure and shear force values is provided by offline analysis using a finite element model of the S3F with the measured displacements as inputs.

S3F Layer Imaging System and Electronics Access Panel

For ordering information please contact our sales department: [email protected] or call us at (937) 630-3012

For technical support, please contact our support department: [email protected] or call us at (937) 630-3012

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