Abstract:
Diabetes Mellitus which is characterized by longstanding hyperglycemia, promote
diabetic peripheral neuropathy (DPN) and peripheral artery diseases (PAD) which
invoke ulcerations especially on the foot plantar ultimately leads to amputations
related morbidity and mortality. Recent clinical studies have identified distinct
associations between DPN and foot plantar pressure, and PAD and foot plantar
temperature. Hence, development of technology to analyze foot plantar pressure
(pedobarography) and foot plantar temperature (pedothermography) to infer DPN and
PAD associated diseases at the onset have recently stirred a significant interest among
the scientific community.
In the present study, we have primarily investigated the possibility of implementing a
highly accurate large piezoresistive platform sensor array (a pedobrographic system)
with an improved readout mechanism. We devised a readout circuit to mitigate
inherent crosstalk interference with an improved scanning architecture implemented
using a decoder-transistor based row driving electrodes and related electronics
compatible with high frequency sensing. Then, the developed readout circuit was
extensively validated and the proposed implementation was able to make
measurements of significant accuracy with errors < 1% while not compromising the
shape accuracy of the measured object. Initiatives were also taken to improve the data
acquisition rate despite massive sensor data influx from 30,000 sensels. A Xilinx
Zynq APSoC based data acquisition system was implemented to scan the entire array
with 30,000 sensels and the analysis showed that the system demonstrated expected
behavior. Overall, the proposed implementation entertained both static and dynamic
pressure measurements of a foot plantar. A subsequent static calibration of the
piezoresisitive sensor array was conducted using weight plates and the calibrated
sensor array was validated against an existing commercial plantar pressure
measurement system to determine its performance.
In addition, possibility of implementing a screening tool for pedothermographic
assessment using near infrared (NIR) technology was investigated to provide an
overall assessment of both foot planters in a single frame and record both regional and
point temperatures of the foot plantar. The proposed thermal imaging system is
anticipated to be used in routine clinical assessment of diabetic foot complications at
diabetic clinics to provide improved diagnostics, thereby contributing to prevention of
diabetic foot ulcerations, amputations and related morbidity.
Citation:
Warnakulasuriya, A.S. (2022). Implementation of a pedobarographic system through effective crosstalk suppression with an all programmable system on chip [Master's theses, University of Moratuwa]. Institutional Repository University of Moratuwa. http://dl.lib.uom.lk/handle/123/21403