Alex Strandberg

Created Raspberry Pi and Arduino projects, including a Home Automation System and a Piggy Bank.

A video showing my Raspberry Pi-powered home automation system that uses a Raspberry Pi and an Arduino Mega, along with other components to control appliances in a room from an iOS app and act as an alarm clock.
Four PowerSwitch Tails turn appliances in a room on or off.
The signals to control the PowerSwitch Tails are sent over 3.5mm audio cables.
The appliances are turned on or off manually or based on a schedule or external sensors.
For example, when the room is too warm, a fan can be configured to turn on.
When a person enters the room, a light can be configured to turn on.
The RGB LED Matrix shuts off when the room is dark.
A reed switch and foot switch notify when a door is opened and when a person leaves the room, respectively.
A Pimoroni Display-O-Tron HAT connected to the Raspberry Pi allows the user to manually control appliances and interact with the system.
The system acts as an alarm clock by playing music at a scheduled time to wake up the user.
The code and documentation for this project are available at: https://github.com/alexstrandberg/Internet-of-Pi-Home-Automation-System

Components: Raspberry Pi, a 12V 5A Power Supply, a 4-Channel Relay Board, a PowerSwitch Tail, and an MCP23017 I2C Port Expander
Controls up to 4 12V DC appliances such as network switches and USB hubs with a web interface and physical buttons.
The Raspberry Pi is powered by a separate 5V power supply.
A web server with MySQL and PHP runs on the Raspberry Pi. The I2C Port Expander handles button inputs, LED outputs, and relay states.
The 4 Channel Relay Board closes or opens the circuit for each appliance to turn the appliance on or off.
The PowerSwitch Tail turns the 12V power supply for the appliances on or off. It is also controlled by a hardware button and the web interface.
By either pressing a physical button or a button on the web interface, appliances can be turned on or off.
The code and other resources for this project are available at: https://github.com/alexstrandberg/Electronics-Power-Management-System

An alarm clock made using an Arduino Mega, a 7-segment and a 14-segment LED Matrix, a Chronodot Real Time Clock, a VS1053 MP3 Player Breakout,
a MCP9808 Temperature Sensor, Adafruit's EZ-Link Bluetooth Module, and USB-powered speakers.
It displays and says the current time, temperature, and date and plays an MP3 file from an SD Card when an alarm goes off.
The Alarm Clock's settings can be changed using a Java program that communicates with the Arduino via Bluetooth.
The code and other resources for this project are available at: https://github.com/alexstrandberg/Arduino-Alarm-Clock

A piggy bank and coin sorter made using a Raspberry Pi, an Arduino, Lego Mindstorms NXT, a coin acceptor, Adafruit's LCD Plate, and a fingerprint sensor.
It counts, sorts, and stores coins.
The Arduino is connected to the Raspberry Pi via a USB hub; it communicates with the fingerprint sensor and detects what kind of coin is inserted.
A Python script outputs information to the LCD display and stores data in a text file.
This project was featured in the January 2016 edition of The MagPi, the official magazine of the Raspberry Pi Foundation. (Page 74)
The code and other resources for this project are available at: https://github.com/alexstrandberg/Raspberry-Pi-Piggy-Bank-with-Coin-Sorter

A security system made by using a Raspberry Pi, an Arduino, a Pi Camera, a reed switch, an RFID reader, and a servo.
It monitors my room and records video if an intruder is detected.
The Arduino is connected to the Raspberry Pi via a USB hub; it sends a serial message when the door is opened while the system is activated.
A PHP webpage displays the latest video taken when an intruder has been detected.
The code and other resources for this project are available at: https://github.com/alexstrandberg/Raspberry-Pi-Security-System

A Raspberry Pi controls a thermal printer to output information from the Internet, Sudoku puzzles, and the Linux "fortune" program.
The Raspberry Pi can be powered by a rechargeable battery pack. It is connected to the Internet using a Wi-Fi dongle. There are 6 LEDs and buttons.
The printer can print the weather, word of the day, Bible verse of the day, and Today in History from the Internet.
The code and other resources for this project are available at: https://github.com/alexstrandberg/Raspberry-Pi-Printer-of-Knowledge

A data logger that logs the temperature wirelessly using an Arduino Uno and an Arduino Mega.
It can display the temperature and log to a microSD card or to the computer.
A thermistor is used to determine the temperature and can be connected to either the transmitter or the receiver.
There is a pair of RF Link Transmitters and Receivers, which can communicate at a distance of up to 500ft (in certain conditions).
When logging to the microSD card, it creates a .CSV file that can be used to generate a graph of the change in temperature over a period of time.
When logging to the computer, a Python code runs in the background, communicating with a local web server with a MySQL database.
I then can view the temperature from anywhere on my local network.
The code and other resources for this project are available at: https://github.com/alexstrandberg/Arduino-Wireless-Temperature-Data-Logger

A RGB LED chaser I built using an Arduino Uno.
There are ten multicolored lights that turn on and off with five different effects.
Pressing a button changes the effect.
A potentiometer can be adjusted to change the speed of the LEDs.
Four shift registers control the LEDs.
A Schmitt trigger regulates the button's input to the Arduino.
The code and other resources for this project are available at: https://github.com/alexstrandberg/Arduino-RGB-LED-Chaser

A safe I built using an Arduino Uno and an Arduino Mega.
When the correct password is entered on the keypad outside the safe, the servo motor inside moves and the safe is unlocked.
A RF transmitter and a RF receiver are used to communicate between the two Arduinos.
The entered password is sent over RF.
An RGB LED is on the outside of the safe to indicate the status.
Each time the safe is locked or unlocked, or when a password is changed or entered incorrectly, it is logged on a microSD card in a microSD breakout board connected to the Arduino Mega.
Every time the safe is turned on, the current date and time is sent over serial to the Arduino in order for the datalogging to work.
The code and other resources for this project are available at: https://github.com/alexstrandberg/Arduino-Safe

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