Electronic Temperature Regulator

Description

The idea of this project is to implement a cooler as well as a heater. This temperature regulator can adjust the temperature of an object within one’s expectation, and can do the real time monitoring of this object’s temperature.

The operation of this temperature regulator is controlled by the Mbed, which sends control signal to the regulator. The control signal is mainly a PWM signal together with another digital signal which defines the operation mode of cooling or heating. And the PWM signal will define the power of the regulator.

At the user end, which is the ATOM PC, there is a GUI which can provide various functions for users to play with this regulator. Users can set their desired temperature through this GUI, can watch the real time temperature change of the object in the GUI, and can also get some system properties.

GUI

As you can see from the user interface, it is mainly divided by two parts, the graphical plot at the top which indicates the history data of current temperature and desired temperature in real time, and the user control panel at the bottom.

In detail, the user control panel has three major functionalities.

The first one is related to connection and graphical settings. To establish communication with Mbed, the user need to initially press the button Search Serial Port, and pick the port connecting with Mbed under the combo box and press Read to complete the communication. Under graphical setting, the user can switch between Compact and Scroll Graph.

The second unit is used to for user to set desired temperature, and by pressing the button Set Temperature, the PC terminal will automatically sent data to Mbed. It is noticeable that the user can choose any preferable units they want, including Fahrenheit and Celsius. To modify the desired temperature, the user can either type in number in the textbox, scroll the track bar, or use voice command which is a fancy character in the user interface. The voice grammar library includes words from “one” to “nine”, “set”, ”cancel”, ”stop” and “exit”.

The last component is called System Monitor. In this panel, all the related data concerning the temperature control system is shown. For example, the current temperature produced by the temperature Sensor, operation mode indicating whether the system is cooing or heating, the Fan Speed and heat sink temperature that detects heat dissipation condition, and finally the PWM percentage of H bridges which indirectly indicates how much power the system is consuming.