The project of A sensor-driven mood lamp in week five Meeting

In the fifth week before bench inspection, students attempted to solder the elements in the board and wire the board with the Arduino board and the LED driver. And the final finished product figure was shown in the follow.
However, due to the short distance between two cavities, the work of soldering was much more difficult than thought. Unfortunately, some wires were soldered together in the board which resulted in the
wrong result in this project. Thus, students abandoned soldering the circuit in the soldering board, and tried to wire the circuit on the bread board.  So, in the afternoon of this Friday, one student hammered at considering the appropriate code for the Arduino board, while another two students wired the circuit in the bread board. After around one hours, the final product was wired successfully and it was shown in the follow figure.

It could be seen that every LED has four pins, and the longest one was connected to the GND, while the other pins (red green blue) was connected to the 5V with a resistor of 330 ohm (high voltage). And the detail information of LED driver has been explained in the week three blog, and the pins in the LED driver were connected to the corresponding locations in the Arduino board. And every infrared sensor utilized three pins with one was connected to the GND, one was connected to the high voltage and one was wired to the output pin in the Arduino board. 

After the model was accomplished, the students would analyze the circuit with program processor in the later time and wrote the report as well.  

The project of A sensor-driven mood lamp in week four Meeting

In week four meeting, initially, students test the operational amplifier.

The equation of the relationship between the output voltage and input voltage were given. The input voltage was measured 2.4 V and the output voltage was recorded 3.3 V, then the ratio of resister R2 / R1 equaled to 0.375. Students attempted to utilize 100 ohm (R1) and 375 ohm (R2) to compose the final operational amplifier, however, when the amplifier was applied in the actual circuit, the LEDs was always light brightly whether the infrared sensor was covered by hand. Then students tried to change their scheme by purchasing a new infrared sensor with the built-in operational amplifier for substituting the original one. Next, one student searched an appropriate infrared sensor in the website and copied one figure in the follow.

Then, the code of  infrared sensor was written by one group student. The whole code would not be shown in the blog because it was a complicated code to be explained in detail. The code mainly implemented functions of  handling the signal. For instance, when the output of IR was 0, the code was operated and calculated by the microprocessor and the nine LEDs would be shine for the outcome.
There was another important issue to clarify that there existed some problems with the Arm 7 board. For instance, the microprocessor board only worked for 10 seconds and overloaded later. Thus, students thought that the Arduino board was a more sensible choice than Arm board. Finally the teacher agreed the students' request for changing the microprocessor board. And the students would research the Arduino board code in the later days of this week.  

Finally, students designed the structure of the circuit diagram which was a little bit different from the original one designed initially, and the final circuit diagram would be drawn in the fifth week.