Intelligent lighting control: use WeChat to realize your home dream

With the development of the Internet, the arrival of the 3G era, cloud computing and cloud networks emerged, and the big data video can be downloaded directly to the smartphone terminal for online viewing, without any stagnation. In such a big environment, smart home technology is also undergoing earth-shaking changes. At this stage, the intelligent control products of well-known brands are still dominated by cable, such as Schneider's C-BUS [1], ABB's I-BUS, Honeywell's H-BUS, Emerson's M-BUS, and Legrand's TCL. SCS-BUS is basically a fieldbus technology. With the maturity of civil RF wireless communication technology, such as WiFi and ZigBee [2], compared with wired technology, it has obvious advantages such as easy installation and disassembly, simple network structure and low cost. These advantages, combined with the fast and big data storage transmission of cloud networks, will set off a revolutionary wireless intelligent control revolution in the fields of lighting, home appliances and security.

Since the official launch of the Tencent WeChat public platform on August 23, 2012, the number of users has far exceeded 300 million. The penetration rate in the city is extremely high. Basically everyone is using WeChat. The new features of WeChat are especially loved by young people in the future. Convenient voice messaging requires very little traffic, which is more economical and cool than phone calls. The picture is sent and received without the need to open the GPRS function, and there is no need to fear that the picture is too big to be sent out, and everything is easily done between the fingers.

The technology described in this paper is an intelligent control technology grafted on the WeChat public platform and its cloud network, hereinafter referred to as WeChat intelligent control. WeChat intelligent control technology is powerful and has a wide range of applications, which can be applied to most intelligent control applications. This article takes smart home as an example and will elaborate on its basic principles and its powerful functions.

The basic application of WeChat intelligent control in smart home is shown in Figure 1. When the user sends text, voice and pictures to the application via WeChat on the mobile phone or computer, the information will soon pass through the 3G network. Transfer to the router near the application. Through the network cable TCP/IP protocol, the router transmits the information to the WeChat intelligent control gateway (a gateway dedicated to WeChat intelligent communication). The gateway performs data conversion while performing protocol conversion and quickly converts the information into New instructions [3]. The new instructions have different manifestations and transmission methods in smart lighting, smart home appliances and smart security applications. They are discussed separately below.

First, the smart lighting of WeChat intelligent control

1. First met the ZigBee protocol

Every family needs to use lamps to illuminate, and the method of controlling lamps is still dominated by ordinary switches at present. A few use infrared remote control, 315MHz and 433MHz RF remote control. WeCs intelligent control system uses 2.4GHz ZigBee protocol [4], and ZigBee adopts on-demand routing AODV algorithm, which can easily realize intelligent networking between lamps, intelligent routing, and wireless information transmission over long distances. As shown in Fig. 2(a), when the ZigBee remote control switch (node ​​No. 1) issues an instruction to the desk lamp of the node 12, according to the AODV algorithm, the command will be transmitted to the node 3, then the node 7, the node 10, and finally the desk lamp. The desk lamp makes corresponding actions according to the instructions, such as opening, closing, dimming, timing, and the like. When node 2 and node 7 on the network are removed, as shown in Figure 2(b), when the command from node 1 is issued, the route will be recalculated. The new route will pass through node 3, node 6, and node 11. Finally, arrive at the node 12 lights. It can be seen that as long as communication can be maintained between every two nodes, the increase or decrease of the node will not affect the communication.

2. Principle of intelligent lighting

(1) Remote control mode

When you use WeChat on your mobile phone thousands of miles away and want to control the lighting of your home, you can simply tap the keyboard to enter text or speak the recording directly to send the instructions over the Internet to your home router. The router then transmits the command to the WeChat intelligent control gateway through the network cable. As shown in Figure 3, the WeChat intelligent gateway encapsulates the instructions according to the ZigBee protocol and radiates them out through the ZigBee antenna. The ZigBee wireless transceiver module [5] is built in the luminaire, and the adjacent two luminaires can communicate with each other. A large number of lamps can form a lighting network. The network will find the optimal transmission route according to the on-demand routing algorithm AODV, and finally send the instructions to the target lamps. The target lamps will immediately respond according to the instructions, such as opening, closing, Dimming, timing, or returning the current working status.

(2) Remote control mode

WeChat intelligent lighting system not only supports remote control of lighting, but also fully compatible with remote control. As can be seen from Figure 3, the control terminals of the short-distance remote control mainly include WeChat intelligent control host, computer, mobile phone and remote control. Their control methods are as follows: The first control method. It is mainly designed for WeChat intelligent control host, computer and mobile phone. These three machines are equipped with corresponding APP application software, which can directly open, close, dim and delay each lamp in the home. All three machines communicate with the router through WiFi. The commands they send to the router are transmitted to the WeChat intelligent control gateway through the network cable. The gateway then transmits the command to the target luminaire through the ZigBee antenna and the lighting network. The luminaire is made according to requirements. The corresponding action, and can return the working status at that time. It can be seen that in this control mode, when the command arrives at the router, it is basically the same as the remote control mode. The second control method is the remote control method. Each luminaire has a position button on the remote control, and function keys such as dimming and delay are shared. For example, if you turn on the desk lamp and adjust it to 50% brightness, the operation is to press the button corresponding to the remote control and the desk lamp. This indicates that the function setting is for the desk lamp, and has nothing to do with other lamps. When the desk lamp receives the "name" command, it will reverse the current state, that is, if the original desk lamp is on, it will be turned off now; if the original desk lamp is off, it will be lit now. After the desk lamp is lit, use your finger to directly click on the 50% position of the continuous dimming ring. This is the easiest way to easily control the luminaire without the need for routers and gateways.

Second, WeChat intelligent control of smart appliances

Remote control mode

The remote control mode is similar to smart lighting. When you use the WeChat sending command to control the home air conditioner, color TV and rice cooker in the field, the command will be transmitted to the router at home through the Internet. The router then The command is transmitted to the WeChat intelligent control gateway through the TCP/IP protocol. As shown in Figure 4, the WeChat intelligent control gateway repackages the instructions and illuminates them through the infrared LED. The infrared rays will reflect when they encounter the wall, and the final signal will reach the target home appliance. The target home appliance will act accordingly according to the command requirements. The communication is over.

However, the control of the rice cooker here is more special, because most rice cookers do not have a remote control function, so here a ZigBee relay switch is connected in series with the power supply of the rice. In this way, when the WeChat intelligent control gateway receives the command to control the rice cooker, it will use the ZigBee communication mode to send the command to the wireless relay switch, and the latter will turn on or off the power supply to the rice cooker according to the instruction.

2. Remote control mode

There are also four control terminals in smart home appliances, similar to smart lighting. WeChat intelligent control host, computer and mobile phone control is the wireless network, passing the router and WeChat intelligent control gateway, and finally the WeChat intelligent control gateway infrared remote control home appliances to complete the corresponding actions, but the LAN and cloud network communication part is omitted. See the above for specific principles.

Edit: liuhai