Soil type | Materials tested | Height of testing | Operation speed or frequency | Performance of study | Reference |
Water | Pipe | 12 m | 3 - 25 kHz | One food buried in sand | [85] |
Space | M2, M16 anti personnel mine | 1 - 13 cm | - | 13 cm | [88] |
Space | Aluminum 5 × 5 × 0.15 cm Iron nail 3 × 0.3 cm | 20 cm 10 cm | 1 kHz | 20 cm 10 cm | [89] [90] |