Psammite — A soil characterization system for environmental analysis

This work describes a geotechnical characterization system applied for soil analysis. This system can measure the acoustic, electrical, and thermal responses of soil, and the luminance and temperature of the site. For the evaluation of acoustic response, two piezoelectric transducers are placed separately by a specific distance, where an electric signal is used to generate an acoustic wave and the other sensor is used to detect received signal. The same setup and distance (50 mm) was employed in a set of two electrodes, where an electrical signal is applied to measure the electrical impedance response. Besides that, capacitive sensors are also inserted into soil. Both sensors (capacitive and electrodes) measure the electrical impedance response, but capacitive sensors are used in small scale measurements (about 1 mm). For the thermal response evaluation, a set of thermistors is used to measure temperature variation. Based on the performed tests, developed system allows the measurement of electrical impedance and thermal response. Besides that, the system also can be used in environmental monitoring, where solar irradiance, air temperature, and soil moisture data can be evaluated.