PI vs PID Temperature Control of an Uncalibrated Portable Heater for Sensors

Wearable heating pads are widely used as therapeutic warmers for tending to multiple health conditions. Precise temperature control is the key to ensuring the safety and effectiveness of the device due to its near-skin application. The paper presents a comparative analysis of temperature control using Proportional-Integral (PI) and Proportional-Integral-Derivative (PID) controllers based on time domain response parameters. The system utilizes an Arduino microcontroller to perform the error calculation between the set point and real-time temperature and accordingly generate PWM pulses to control the actuator driving the heating pad. The device features three different modes of operation based on the analog output voltage from an external driving circuit. Alongside, characterization data, system design and implementation of controllers, a comparative time domain response parameter analysis based on experimental data is also presented.