Embroidered Flexible Elastic Textile Antenna as Strain Sensor

This paper is focused on the design and testing of embroidered flexible elastic textile antennas for strain sensing based on the evaluation of changes in their electrical parameters. Samples of planar textile antennas for strain sensing were prepared by embroidered technology on elastic fabric. Antennas were of different shapes as split-ring resonators in 2 widths, bow tie, dipole, and as embroidery styles were chosen outline, meander, crossing. Conductive patterns were embroidered with hybrid threads containing polyester fibers and silver-coated copper wires. The stretching of the embroidered antennas was performed in one direction with a step of 10 mm on the stretching jig to their possible maximum. Results show that the resonant frequency decreases with increasing elongation for some antenna samples; it depends on the shape and embroidery style of the designed samples. Contour embroidery style shows a much better dependence on stretching in comparison with the crossing style.