Combined application of FBG and PZT sensors for plantar pressure monitoring at low and high speed walking.
Study Goal
The researchers aimed to evaluate the combined use of FBG and PZT sensors for monitoring plantar pressure during walking at low and high speeds.
Results Summary
The study found that FBG sensors are suitable for static and slow-walking conditions, while PZT sensors are more accurate for high-speed walking and running, with pressure measurements ranging from 100 to 1000 kPa depending on speed and foot region. The combined use of both sensors enables comprehensive plantar pressure monitoring from static to high-speed conditions.
Population
Healthy male subject
Effective Dosage
Not applicable
Duration
Not specified
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
Fibre Bragg Grating (FBG) sensors embedded in carbon composite | neutral | average pressure sensitivity | - | 1.3 pm/kPa | obtained | #1 |
Fibre Bragg Grating (FBG) sensors embedded in carbon composite | neutral | resolution | - | nearly 0.8 kPa | obtained | #2 |
Fibre Bragg Grating (FBG) sensors | no change | static and low-speed walk generated foot pressure | - | - | found to be suitable for measuring | #3 |
PZT patches | neutral | sensitivity | - | 7.06 mV/kPa | obtained | #4 |
PZT patches | neutral | pressure resolution | - | 0.14 kPa | obtained | #5 |
PZT sensors | no change | foot pressure measurement during high speed walking and running | - | - | found to be suitable for | #6 |
PZT sensors | no change | pressure during walking at high speeds | - | - | are more accurate for measurement of | #7 |
FBG sensors | no change | static and quasi-dynamic (slow walking) conditions | - | - | found to be suitable for | #8 |
walking speed variation | increase | measured pressure below the forefoot | a healthy male subject | from 400 to 600 kPa | varied | #9 |
walking speed variation | increase | measured pressure below the heel | a healthy male subject | from 100 to 1000 kPa | varied | #10 |
walking speed variation | increase | walking speed | a healthy male subject | from 1 kilometer per hour (kmph) to 7 kmph | varied | #11 |
BACKGROUND: Clinical monitoring of planar pressure is vital in several pathological conditions, such as diabetes, where excess pressure might have serious repercussions on health of the patient, even to the extent of amputation. OBJECTIVE: The main objective of this paper is to experimentally evaluate the combined application of the Fibre Bragg Grating (FBG) and the lead zirconate titanate (PZT) piezoceramic sensors for plantar pressure monitoring during walk at low and high speeds. METHODS: For fabrication of the pressure sensors, the FBGs are embedded within layers of carbon composite material and stacked in an arc shape. From this embedding technique, average pressure sensitivity of 1.3 pm/kPa and resolution of nearly 0.8 kPa is obtained. These sensors are found to be suitable for measuring the static and the low-speed walk generated foot pressure. Simultaneously, PZT patches of size 10 × 10 × 0.3 mm were used as sensors, utilizing the d<formula>_{33}</formula> (thickness) coupling mode. A sensitivity of 7.06 mV/kPa and a pressure resolution of 0.14 kPa is obtained from these sensors, which are found to be suitable for foot pressure measurement during high speed walking and running. Both types of sensors are attached to the underside of the sole of commercially available shoes. In the experiments, a healthy male subject walks/runs over the treadmill wearing the fabricated shoes at various speeds and the peak pressure is measured using both the sensors. Commercially available low-cost hardware is used for interrogation of the two sensor types. RESULTS: The test results clearly show the feasibility of the FBG and the PZT sensors for measurement of plantar pressure. The PZT sensors are more accurate for measurement of pressure during walking at high speeds. The FBG sensors, on the other hand, are found to be suitable for static and quasi-dynamic (slow walking) conditions. Typically, the measured pressure varied from 400 to 600 kPa below the forefoot and 100 to 1000 kPa below the heel as the walking speed varied from 1 kilometer per hour (kmph) to 7 kmph. CONCLUSIONS: When instrumented in combination, the two sensors can enable measurements ranging from static to high speed conditions Both the sensor types are rugged, small sized and can be easily embedded in commercial shoes and enable plantar pressure measurement in a cost-effective manner. This research is expected to have application in the treatment of patients suffering from diabetes and gonarthrosis.