Week #7 - Journal

1: Setting Up the Circuit on a Breadboard

After finalizing the design and code in Tinkercad, I replicated the circuit on a breadboard:

• I connected the 4x3 keypad to the Arduino Uno, following the pin layout from the simulation.

• The LCD display was hooked up using the I2C module, which simplified the wiring as it only required two data lines instead of multiple.

• I wired the micro servo motor to the Arduino to control the gate's opening and closing mechanism.

2: Uploading the Code for Testing Each Component

Before combining everything, I tested each component individually to ensure everything worked properly:

1. LCD Testing: I uploaded a simple "Hello World" code to the Arduino to check if the LCD was displaying correctly.

2. Servo Motor Testing: I uploaded a basic servo control code to verify the servo rotated smoothly in response to the signals from the Arduino.

3. Keypad Testing: I tested the keypad by uploading code that would display the key presses on the serial monitor, ensuring the Arduino could read input from the keypad correctly.

Step 3: Uploading the Full Code to the Arduino

Once all components were working individually, I uploaded the full code for the system:

• The code controlled the password input via the keypad, displayed messages on the LCD, and triggered the servo motor based on the correct or incorrect password input.

Step 4: Fabrication Using Cardboard

For the physical gate, I used cardboard as my material. I manually cut the cardboard pieces using a cutter:

• The design was simple: a basic gate structure with a rotating part controlled by the servo motor.

• I glued the cardboard pieces together using hot glue.

Step 5: Assembling the Project

After the cardboard gate was ready, I attached the servo motor to the gate. I mounted the Arduino, LCD, and keypad onto the cardboard structure, securing everything with hot glue and double faces for stability.

Step 6: Final Testing

I tested the final setup by entering the default password (123) to open and close the gate, ensuring the system responded correctly to both the correct and incorrect inputs. Adjustments were made to the timing and functionality as needed.

This simple setup was easy to fabricate using cardboard and worked smoothly with the tested components!

1: Keypad Miscommunication

I ran into a problem because the tutorial I was following used a 4x4 keypad, but I only had a 4x3 keypad. This meant the tutorial’s code was set up for 16 keys, while my keypad only had 12. So, I had to make some changes to the wiring and code to match my keypad.

Solution:

I went into the code and removed the extra row and column references. This involved tweaking the wiring to match my 4x3 keypad and adjusting the code to handle fewer keys. After some trial and error, I got everything working smoothly.

2: Servo Power Struggles

The servo motor wasn't working as expected. I initially powered it directly from the Arduino, but that didn’t provide enough juice, so the servo wasn’t responding properly.

Solution:

I realized the Arduino couldn’t supply enough power for the servo. To fix this, I used a 9V adapter to power the servo directly, giving it the extra power it needed to function properly. After that, the servo worked smoothly!

3: LCD Display Issues

The backlight on my LCD display was super dim, so the words were practically invisible. I tried to adjust the potentiometer to fix the contrast, but it was so corroded that the screwdriver couldn’t even budge it.

Solution:

Since I couldn’t fix the potentiometer, I went to San3a Academy, and with Orabi's help, I ended up replacing the entire LCD. After swapping it out, everything worked perfectly, and the display was nice and clear!

4: Mounting the Components on Cardboard

At first, I made the cardboard base too small, which became a real problem when I tried to fit all the wires and the Arduino inside. It was like trying to fit a giraffe into a compact car—just wasn’t going to happen!

The skills I gained this week, like troubleshooting hardware issues, adapting code for different components, and designing flexible setups

• Coding adjustments: Modifying the code for the 4x3 keypad taught me how to tailor code for specific hardware, which is key for any custom project.

• Power management: Learning how to properly power the servo with a 9V adapter instead of relying on the Arduino will help me avoid similar power issues in the future.

• Efficient layout design: Ensuring I have enough space for all components, like with the cardboard base, will guide me in designing a more organized and spacious setup for my final project.

• Component swapping: Replacing the faulty LCD showed me how to handle hardware failures quickly, a handy skill for dealing with unexpected challenges during the final project.