Insole optical fiber Bragg grating sensors network for dynamic vertical force monitoring

Abstract

In an era of unprecedented progress in technology and increase in population age, continuous and close monitoring of elder citizens and patients is becoming more of a necessity than a luxury. Contributing toward this field and enhancing the life quality of elder citizens and patients with disabilities, this work presents the design and implementation of a noninvasive platform and insole fiber Bragg grating sensors network to monitor the vertical ground reaction forces distribution induced in the foot plantar surface during gait and body center of mass displacements. The acquired measurements are a reliable indication of the accuracy and consistency of the proposed solution in monitoring and mapping the vertical forces active on the foot plantar sole, with a sensitivity up to 11.06 ?? pm / N . The acquired measurements can be used to infer the foot structure and health condition, in addition to anomalies related to spine function and other pathologies (e.g., related to diabetes); also its application in rehabilitation robotics field can dramatically reduce the computational burden of exoskeletons’ control strategy. The proposed technology has the advantages of optical fiber sensing (robustness, noninvasiveness, accuracy, and electromagnetic insensitivity) to surpass all drawbacks verified in traditionally used sensing systems (fragility, instability, and inconsistent feedback).

Insole Optical Fiber Sensor Architecture for Remote Gait Analysis—An e-Health Solution

“…There are several types of F V sensors, which are characterized essentially by the transduction mechanisms and technology used for converting forces into electrical signals, such as piezo resistivity and capacitance [10,[13][14][15]. In addition to these electronic mechanisms, other transduction methods, as OFSs are also frequently used for the measurement of these type of forces [2][3][4]16].…”

“…Vertical force sensors are nowadays required for a wide number of applications, in diverse areas such as industrial production and structural health monitoring, artificial intelligence, robotic exoskeletons and other health applications [2][3][4], [8][9][10][11][12][13][14][15]. There are several types of F V sensors, which are characterized essentially by the transduction mechanisms and technology used for converting forces into electrical signals, such as piezo resistivity and capacitance [10,[13][14][15].…”

“…Specifically, sensors capable of measuring F V and F S simultaneously are highly required for haptic perception of robotic hands, prosthetic skin and to monitor the stress under the foot to prevent its ulceration [2][3][4][17][18][19][20][21][22][23].…”

“…Our previous efforts have concentrated on the pressure distribution, through a strategically placed network of optical fiber sensors (OFSs) [2][3][4]. In the presented work, we take a step forward by presenting the design and implementation of a fiber Bragg grating (FBG)-based platform, for simultaneous measurement of shear and vertical forces, which can be useful in various applications, in addition to e-Health.…”

“…Basically, e-Health is seen as an approach to help elder generations and patients with chronic illness to live an active life, without comprising their mobility or daily routine. Following this direction and towards improving the quality of life of physically impaired citizens by increasing their mobility, our team has been working in different practical solutions for continuous remote monitoring of patients [2][3][4].…”