Chapter 4. Energy Management with Light Sensors and Extending Use Cases

We will follow on from the previous chapter with some new home automation devices and sensors, which are usable with Intel Galileo, and are related to energy management. In this chapter, we will try to focus on the lighting of our home. We'll check out some existing devices which you can use with Intel Galileo.

While finalizing the previous chapter, we made an introduction to the process of sending and receiving commands to Z-Wave devices with a USB controller; here, we will get into more detail about the use of Z-Wave commands.

Using light sensors

Light sensors are used to measure the current intensity of light in the ambient environment. Light intensity is measured in lumen units depending on the sensor and the amount of light emitted by the source. Lux is also used to indicate the light amount in the environment Lux means the luminous flux per unit area, which is equal to one lumen per square meter. For example, when there is full daylight, the amount of light is around 10000-25000 Lux. During full moon days, the amount of light is around 0.267 Lux.

Light intensity data can help you to automate your lighting system to switch it on or off. Switching off light automatically with your home automation system, where light intensity is high enough to see, will save energy. You can also create your own luminance data table and use it to automate your application to regulate when to switch lights on or off.

There are many sensors compatible with the Intel Galileo pinout. You can either use photocells or digital light sensors...

Smart light bulbs

There is an increasing trend of using new wireless light bulbs for home appliances. There are many light bulbs available that use Zigbee, Z-Wave, Bluetooth 4.0, and other home automation protocols. Some of the light bulbs only allow remote switching on and switching off; some allow remote dimming of the light intensity of the bulb. New LED Light Bulbs also allow you to set the color of the light bulb by sending the RGB value to the light bulbs.

Using Philips Hue with Intel Galileo

One of the most popular wireless light bulb systems is Philips Hue. The Philips Hue system includes a bridge and remote led bulbs. The Philips Hue bridge connects with a home network to allow the user to manage light bulbs via a local network connection. Philips Hue bulbs use the Zigbee Light Link protocol, and the Philips Hue bridge controls the bulbs.

Philips provides software development kits for users to access the bridge and control light bulbs with REST API. Official SDKs and tools are provided...

Extending a home automation system with lighting control

We looked at lighting sensors and devices used for home automation. Let's go back to our home automation application to extend its use cases by connecting our Z-Wave wall plug to a desk lamp and using a Z-Wave lamp holder to read illumination values from a remote Z-Wave sensor.

In the previous chapter, we just made a brief introduction to using Z-Wave devices with a Z-Wave USB controller. During the course of this chapter, we will learn more about Z-Wave commands and how to control lighting devices from our Z-Wave USB controller.

The following picture shows our new device, a Z-Wave lamp holder produced by Everspring. We have included it in the Z-Wave network, as defined in the previous chapter, and we will add the ability to switch on and switch off the device remotely from Intel Galileo.

Our next circuit is a desk lamp attached to a Z-Wave wall plug from Fibaro. We have already included the device in our Z-Wave network. We will add...

Summary

In this chapter, we tried to cover devices and sensors related to lighting and light intensity measurement and their use in the Linux application running on Intel Galileo.

In the first part, we looked into the sensors compatible with Intel Galileo, which may help you obtain light intensity measurement and use the data for your home. Then we followed up with remote light bulbs and mentioned the popular ones such as Philips Hue and its SDKs, which are compatible with Intel Galileo.

Remote light bulbs are getting more popular by the day with other protocols, especially with the Zigbee Light Link protocol. With the information given in this chapter, you should have an idea on how to automate your lighting system. We set up some basic circuits to show the usage. We connected our remote wall plug to a desk lamp and used a Z-Wave lamp holder for the room bulb. You can extend these cases by adding different devices and use remote wall plugs or bulbs as you need.

Along with this chapter, we...