SENSORS: Types, Characteristics and Aplications

Purpose: Sensor, designates devices which are sensitive to some form of energy that exists in the environment where the sensor is inserted. They are sensitive to a physical or chemical quantity and the sensor typically transforms the variation of this quantity in electrical current or voltage variations, processed by a microcontroller. Some examples of sensors are those of temperature, humidity, pressure, light, gas, pH and radiation. In terms of applications some different areas can be referred such as agriculture, meteorology, environment and industry. In agriculture, sensors of humidity, temperature, rainfall, and pH are common. In addition, sensors of pressure, wind direction and speed, and solar radiation - visible and UV, are also common in meteorology. To detect environment pollution, gas sensors are very much used. In industry, sensors of presence, position, proximity, speed, acceleration and level are more often used. The main goal of this work is, at an early stage, the study of different sensors, its parameters and applications; at a second stage, a study of rainfall and humidity sensors for use in meteorology and agriculture will be done. Expected results: In the first stage and to characterize the sensors, parameters such as sensitivity, precision, accuracy, linearity, range, and speed of response are studied. It will be shown the parameter definition, the mathematical description, the unit of measurement, the graphical representation and some examples. At the second stage the operation of humidity and rainfall sensors is discussed and the project, development and measurement of this type of sensors will be done.