Mechatronics - On/Off Temperature Control

One of case studies at Mechatronics class at Columbia University taught by Dr. Fred R. Stolfi. This case study is a dynamic system investigation of an important and a common mechatronic system: a thermal close-loop system.

The main apparatus includes:

A microcontroller, PIC 16F74
A resistive heater (SRMU 100202P)
Two temperature sensor (AD590 and AD22100)
A fan.

The film of On/Off temperature control:

The specification of resistive heater:

Specifications	Value
Manufacturer	Omega Engineering Inc
Model Number	SRMU 100202P
Heater Resistance	350 ohms
Heater Area	4 in2
Heater Thickness	0.1 in

The specification of temperature sensor are listed below:

Specification	AD590	AD22100
Rated Temperature Range	-55℃ to 150℃	0℃ to 100℃
Nominal Output at 0℃	273.2 μA	1.126 V
Nominal Output at 25 0℃	298.2 μA	1.587 V
Temperature Coefficient	1μA / ℃	18.43 mV/℃
Absolute Error	± 5.5 ℃	± 2.0 ℃
Nonlinearity	0.8 ℃	0.5 ℃

The essential difference is that AD590 (plate) produce a current proportional to temperature while AD22100 (ambient) produce a voltage proportional to temperature.