An Arduino-based low-cost hardware for temperature control

Abstract

This paper describes a simple digital temperature control system where the popular LM35DZ sensor is used to sense the temperature of a resistive heating element and to provide a feedback to an Arduino microcontroller board. By subtracting the measured temperature from the desired temperature, a value of error is then processed by a conventional PID controller which provides an adjustment signal and drives a bipolar junction transistor in order to minimize or remove that error by a simple ON/OFF switching of the power to the heating element. The control is also done using logic controllers such as ON/OFF and hysteresis controllers. The evaluation of each controller performance is based on rise time, overshoot, steady state error and the most common performance criterion which is the integral of the absolute value of the error. Besides that, the arduino integrated development environment (IDE) software is used to write the program code. Moreover, other languages are used to program the Arduino such as Matlab support package for Arduino hardware, Flowcode IDE and mBlock.