Since I had never used a photoresistor before, I started off with making a project based on that. After some quick research, I realized that a photoresistor works by changing it's resistance based on the amount of light that hit's its surface. This is useful in a circuit because the arduino can then sense the variable resistance and thus sense the change in light. By using an LED to simulate changes in daylight and programming the Arduino to control a motor based on the photoresistor, I had myself a solar operated motor!

For my next experiment, I decided to mess around with the LCD.  After following some circuit diagrams that I found online and testing out the pre-written code for the LCD game that I found online, I decided to try creating my own timer and scrolling text. This was a bit more fun since it was my own programming. I also noticed how similar this screen looks to the ones used on water bottle refilling stations, and I think there could be a lot of interesting applications of this little screen in future projects.

First, I created a program to utilize the ultrasonic sensor that came with the mBot. This allowed me to track the distance of objects in front of the mBot, and when the distance became too small, the mBot can back up and turn in a random direction to find a bettter path with less obstacles. This worked well, but it would be improved with better visibility from the sides. This will be covered shortly.

Next, I programmed the mBot to use the IR sensor on the bottom of the robot to track different surfaces. This allowed me to make the mBot follow a black line. When both IR sensors are inside the line, the mBot moves forward. When one side strays too far, the mBot turns to correct itself. When both IR sensors are out, then the mBot backs up to find the line.

With the IR sensors added and bumper attached, I decided to create an advanced version of my obstacle avoidance code. First, I added logic to my program that takes in data from the side sensors to make guided decisions on the best direction to turn. Next, I decided to combine the program with my black line follower code because the black line sensor will detect black if the floor is too far away. Thus, I had created myself a robot that both prevents itself from hitting a wall and prevents itself from going over an edge.

Next, I decided to modify my advanced obstacle avoidance program so that it only uses the right IR sensor. This allowed me to create a program that keeps the mBot moving forward while staying within a certain distance of the wall on its right side. It can handle corners really well once the timing is calibrated correctly. As shown, it can also go around a corner to find the next wall when the original wall ends! This could be pretty convenient for the purpose of mapping a room, and I think I'll try to do that in a future project.