Design, Fabrication, and Experimental Characterisation of a Low-CostPiezoelectric Pavement Tile for Footstep Energy Harvesting: An IndoorPilot Study at a University in Somalia

Abstract

Pedestrian traffic provides a small but persistent mechanical input that can be converted into electrical signals for distributed sensing. This study designed, fabricated, and experimentally characterized a low-cost piezoelectric pavement tile using components available in Mogadishu, Somalia. The 24 × 16.5 cm prototype contains ten PZT-5A ceramic discs connected in parallel beneath a rigid acrylic plate and a 10 mm expanded polyethylene foam layer. The array feeds a four-diode bridge rectifier, a 10 µF capacitor, and an Arduino UNO used for voltage acquisition and relay control. Controlled indoor tests produced two independently acquired datasets. In the qualitative loading series, conditioned voltage increased from 0 mV at no load to 25–50 mV under a full footstep; eight repeated firm-footstep trials yielded 24.6 ± 1.8 mV (CV = 7.5%). In the participant series, one-foot loads of 245.25, 343.35, and 490.50 N produced capacitor voltages of 0.20, 0.35, and 0.50 V. Corresponding recovered energies were 0.200– 1.250 µJ, average powers 0.500–3.125 µW, and estimated system-level efficiencies 5.44 × 10⁻⁵–1.02 × 10⁻⁴%. Current was below instrument resolution, so energy and power were derived from capacitor voltage. The two voltage series differed by approximately one order of magnitude and were therefore analysed separately. The prototype reliably detected footsteps but did not provide useful load power, identifying event sensing rather than energy supply as its realistic application.