The automated LED control system described here was designed to control Philips Hue smart bulbs.
A Raspberry Pi computer is used to control a 24-hour cycle of bulb color changes that range from cool white in the morning to warm colors in the evening.
These color changes emulate sunlight colors from sunrise to sunset.
This is an example of human centric lighting.
This cycle matches our circadian rhythm and has many health benefits, including better sleep and relaxing moods.
Kelvin color temperatures are used to control the bulbs.
The Philips Hue API is used to control groups of bulbs.
The software application running on the Raspberry Pi connects to the Philips Hue Wi-Fi bridges that control the bulbs and to a website on the Internet that stores minute-to-minute data in a SQL database.
Data in the website database is used to display a real-time graph of color changes. This graph acts as a monitor for the system.
Individual color schedules can be created for four periods during the day. These are:
1. Morning (Sunrise to 12:00 PM)
2. Afternoon (12:00 PM to Sunset)
3. Evening (Sunset to 12:00 AM)
4. Sleep (12:00 AM to Sunrise)
The time ranges for these periods can be adjusted.
The user interface (Internet webpage) allows a user to create a bulb color range for each of the four periods.
The Raspberry Pi attached to the home’s local Wi-Fi network runs the schedule and sends data to the website database.
The smart bulbs change color gradually during the period, starting with the beginning Kelvin value moving to the ending Kelvin value.
In this LED Home Automation project, emails created in Gmail can be used to control the Philips Hue bulbs from anywhere in the world that has an Internet connection.
The “GROUP 1 ON” email title is a control command that tells the home automation controller (Raspberry Pi) to send a command to the Philips Hue hub to turn on the group of bulbs assigned to the kitchen.
The control program on the Raspberry Pi reads incoming emails and controls the Philips Hue bulbs.
For example, the bulb color in a lamp could be used as an ambient email alert for emails that contain certain key words in the TITLE, or that are FROM a certain email address.
A motion activated lighting control system (with camera) for the Philips Hue is under development.
A vibration sensor on a Raspberry Pi can detect tampering at doors and windows before a break-in occurs. These devices can communicate with a Philips Hue hub to turn on lights when vibrations are detected.