Introduction to Robotics (2022 - 2023)

Introduction to Robotics laboratory homeworks, taken in the 3rd year at the Faculty of Mathematics and Computer Science, University of Bucharest. Each homework includes requirements, implementation details, code and image files.

Homework 1 (RGB LED)

Task:

A separate potentiometer is used in controlling each color of the RGB LED (Red, Green and Blue). The control is done with digital electronics (the values of the potentiometers are read with Arduino, and the corresponding mapped values are written to the pins connected to the led).

Components:

• Arduino Uno microcontroller board
• Breadboard
• RBG LED
• Potentiometers (x3)
• Resistors and wires (per logic)

The showcase video can be found here.

Photo of the setup:

Homework 2 (Crosswalk)

Task:

Building the traffic lights for a crosswalk. Two LEDs are used to represent the traffic lights for pedestrians (red and green) and three LEDs are used to represent the traffic lights for cars (red, yellow and green). By default, the system will show green for cars and red for pedestrians. The button has the role of signaling a request from pedestrians for crossing the street (it has no effect if the system is already processing such a request). The buzzer will emit a beeping sound when it's green for pedestrians. There are 4 states which the system goes through:

• State 1 (default, reinstated after state 4 ends): green light for cars, red light for people, no sounds. Duration: indefinite, changed by pressing the button.
• State 2 (initiated by counting down 8 seconds after a button press): yellow light for cars, red for people and no sounds. Duration: 3 seconds.
• State 3 (initiated after state 2 ends): red for cars, green for people and a beeping sound from the buzzer at a constant interval. Duration: 8 seconds.
• State 4 (initiated after state 3 ends): red for cars, blinking green for people and a beeping sound from the buzzer, at a constant interval, faster than the beeping in state 3. This state lasts 4 seconds.

Components:

• Arduino Uno microcontroller board
• Breadboard
• LEDs (x5)
• Button
• Buzzer
• Resistors and wires (per logic)

The showcase video can be found here.

Photo of the setup:

Homework 3 (7-Segment display drawing)

Task:

Switching the state (On/Off) of each segment individually. The selection of the segment for change is done by moving between segments using a joystick. The movement between segments is natural (meaning they can jump from the current position only to neighbours, but without passing through "walls"). There are 2 states which the system goes through:

• State 1 (default, but also initiated after a button press in State 2): Current position blinking. Can use the joystick to move from one position to neighbours. Short pressing the button toggles state 2. Long pressing the button in state 1 resets the entire display by turning all the segments OFF and moving the current position to the decimal point.
• State 2 (initiated after a button press in State 1): The current segment stops blinking, adopting the state of the segment before selection (On or Off). Toggling the Y axis changes the segment state from ON to OFF or from OFF to ON. Clicking the joystick saves the segment state and exit back to state 1.

Components:

• Arduino Uno microcontroller board
• Breadboard
• 7-segment display
• Joystick
• Resistors and wires (per logic)

The showcase video can be found here.

Photo of the setup:

Homework 4 (4 Digit 7-Segment display and shift register)

Task:

One joystick axis is used to move through the 4 digit 7 segment display digits. The blinking DP LED shows the current position. When pressing the joystick button, the current position becomes locked in (DP LED stops blinking) and the other joystick axis is used to increment or decrement the digit shown. The digits shown are represented in hex (from 0 to F). Pressing the button again will save the chosen digit and return to the display digit selection phase. When long pressing the button while in the selection phase, the display will reset showing '0' on all digits and the current position is set to the rightmost digit.

Components:

• Arduino Uno microcontroller board
• Breadboard
• 4 Digit 7-segment display
• 74hc595 shift register
• Joystick
• Resistors and wires

The showcase video can be found here.

Photo of the setup:

Homework 5 (LCD Menu and mini game)

Task:

A game menu on the LCD. When powering up the system, a greeting message is shown for a few seconds. The menu contains the following categories: Play (starts the game), How to play (instructions), Settings, Highscore values, About section (author details and game title). When it comes to settings, it provides a name changing option, difficulty choosing, contrast control of the LCD, matrix and LCD brightness control and mute/unmute app sounds. As for the minigame, it's about a point which tries to 'eat food' spawned randomly on the map (which is the 8x8 LED matrix). Each food eaten increases score by 1. Score is shown on the LCD. To return to the menu, no action must be made for a few seconds.

Components:

• Arduino Uno microcontroller board
• Breadboard
• LCD
• MAX7219 Driver
• 8x8 LED Matrix
• Joystick
• Resistors and wires

The showcase video can be found here.

Photo of the setup: