Table 2.
Comparison Table of Proposed Sensor and Other RF Strain Sensors.
| This Work | [29] | [30] | [31] | [32] | [33] | |
|---|---|---|---|---|---|---|
| Substrate | Ecoflex | Kapton tape | Si | PDMS | RT/Duroid 5880 | Kapton |
| Conductive Material | EgaIn | Au | Au | Au | Cu | Cu/Al |
| Fabrication Method | 3D printing | Lithography, Evaporation | Lithography, Evaporation | Spin coating, Evaporation, Photolithography | Lithography | Lithography, Manual assembly |
| Maximum Strain Level (%) | 45.72 | N/A | N/A | 9.78 | 0.2 | 1 |
| Tuning Ratio (%) | 12.31, 14.95 | 5.69 | 0.21 | 5.14 | 0.14 | 2.35 |
| Number Of Detect Direction | 2 | 1 | 1 | 2 | 1 | 2 |
| Resonant Frequency (GHz) | 2.03, 3.68 | 12.3 | 0.4742 | 700 | 5 | 3.62 |
| Q factor | 4.58~4.83 | 12–18 † | N/A | 3~4 † | 40~49 † | 40~50 † |
| Resonator | Metamaterial | Metamaterial | Metamaterial | Metamaterial | Patch Antenna | Open loop |
† It is estimated from frequency response figures.