En este proyecto hemos realizado una alarma antirrobo, con circuitos de proximidad y sonoros.
Los resultados principales fueron que el sensor de proximidad al momento en el que una persona se acerca se activa y hace prender los leds, luego cuando la persona abre la tapa se activa la alarma de sonido y esto ahuyentara a esa persona que quiera tomar nuestros objetos importantes.
This project is a prototype that works thanks to four sensors stage, an audio generator stage, a switching stage, and another stage of single amplifiers for each earphone which generates an audio signal established by a protocol of sounds.
This singular protocol has variables like amplitude, frequency and continuity of the audio signal. Each sensor is made off a transmitter whit its receptor of infrared signal. Once we have developed the sensor, we proceed to calibrate it until reaching the desired range. The audio generator stage is an astable oscillator that changes its frequency depending on the signal that is received by the sensors. The switching stage has been designed by a transistor that works as a switch, working in the cut and saturation state. The amplifiers are designed for little signals generating two levels of amplitude adequate to the human ear.
The first zone includes frontal sensors to detect obstacles and regulates the signal frequency for the sound in both headphones depending of the distance of the obstacles.
The second zone includes surface sensors; these generate a change in the signal amplitude in the sound for headphones in two values, a high one, and a low one, it depending on whether or not there is a vacuum in the surface.
The third and fourth zone includes lateral obstacle's sensor calibrated at an especific distance that modifies the audio signal corresponding to each headphone in an independent way between two levels, a continuous and a discontinuous one.