Week 8

Week 8

With new parts to work with, I was able to continue my work. I fitted the new thermistor on to a separate board to make it more robust and reusable.
     
                               

Then, to achieve a proper thermal contact with the thermistor and the pseudo heater (a simple 20 ohm resistor, to generate heat when a voltage is applied), I used thermal paste on the separate board and resistor.

                                                               

With the complete circuit I have made, it was all ready to be tested. With this testing setup, I was able to record at which voltage the LED would turn off.


                            

Although it was messy, I was able to find that the voltage reached about 2.2 volts then my LED turned off completely.

                               

The heat slowly dissipated after I disconnect the resistor and the system returned back to normal. The Oscilloscope here shows the rise at the beginning to 2.2 and slowly going back down over time. This is precisely what I wanted to see in order to move on to implement my PID controller. It feels rewarding when your work and code really go together to finally achieve your final goal. Next week I'll show my PID controller code that will control the heater.

-3/31/17