The history of technology and automation
In saying “Necessity is the Mother of Invention” to conclude that man since the dawn of history has sought to facilitate his creativity to invite tools that helped him to live from Stone Age to Cooper, Bronze, and Iron Ages that each age developed the following age. He built growth of the ancient civilizations such as Egyptians that invented and used many simple machines and other ancient civilizations that improved many technologies for example Greek invented watermill which was the first human-devised motive force. The industrial revolution in Britain which is individuated by the promotions in the areas of textile manufacturing, mining, metallurgy and transport driven by the development of the steam engine. That changed the whole course of man’s life and the subsequent revolution in electricity, electronics and communications led to the development of technology.
Technology has transformed the lives of people world over, has saved us loads of time and has made life easier for all of us.
The idea of remote control that controls machines after the World War 1 in Germany gave birth of automation. Automation can be defined as the use of control systems, Human activities and applications in all areas of life has rapidly expanded from the combination of automated devices with mathematical and organizational tools which created complex systems that have been used in industrial, commercial, economic, and social ranges of man’s life. The evolution of controllers and automation has been developing and still continue to develop to these days.
What is Home Automation
Home is the word that refers to relaxing and rest after a long day of work, that when you get home you need all the reasons of relax, in the past man was coming home and was finding hit wife had created the comforts for him, but then women choose to be man’s partner in all areas of life, so to find technology took the rule and start to create comfort for both man and woman at home.
The first appearance of home automation was the TV remote control and then inventions followed one another.
Home automation is a system in which user can control his home subsystems using an interface provided by the system to achieve the purpose of home automation.
The idea of home automation came from modern home which filled with electronic apparatus and appliances -which are the home subsystems foundation- to make life easier at home, more secure, and more comfortable that the user can control his house while he is relaxing or working.
When the user leaves his home to go on holiday, he loses all control over the functions of the house while he is away and cannot tell whether someone has punctured the security or whether he had left the living room light on. If the alarm has been triggered at his home, there is no way that the user can become aware of this unless he returns to his compromised home. In order for the system be useful, the appliances must be able to be moved around the house and still retain their ability to communicate with the system. A degree of automation is needed in a house so that certain functions in the house occur automatically, for example the outside light can turn on when it becomes dark outside.
There is a need for a reliable, secure and interactive system that exercises full control over the electric and electronic aspects of the house, with the potential to be accessed from across the globe.
A home control system controls the user’s whole house, triggering routines and events involving Home Subsystems. An automation system controls a collection of â€œHome Subsystemsâ€.
A Home Subsystems includes light fixtures, the heating-cooling system, security components, entertainment, as well as devices like motorized drapes or any other condition that the user selects. Is a system that even when operating automatically provides benefits to the system user. A home automation system puts two or more Home-Subsystems under the control of one central controller which is PIC microcontroller and the user interface attached to the controller for example touch screen, key pad, handheld remotes, or a PC which we will describe it later in this chapter.
The Smart House system would adjust the power supplied to each appliance according to need. Each appliance is provided with sufficient power to provide for its peak use. In addition, the Smart House controllers could schedule the operation of heavy power consuming appliances (such as dishwashers, electric water heaters, and air conditioners) to take maximum advantage of off-peak electric rates. These adjustments could result in lower utility costs.
Features that provided by Home Automation
Home automation system can provide many benefits that make home safer, more comfortable, by employing sensors and control systems to monitor home and provide services.
- The home automation system can make the user be able to control his own home while he relaxing sleeping even while he is working.
- The home automation system makes the user be able to control lighting that he can change light with his mode and requirement.
- Security is one of the important benefits that can be provided by home automation system even during the absence of the user, that if there someone trying to breach house the system can release the alarm, lock all the exits until the user comes and reset the system.
- The home automation system can provide a system prevent fires by smoke sensors that senses for smoking if there the system release the alarm and the water sprinkles start spraying water.
- Home automation system can control the temperature of house by controlling AC.
- There is a large unexploited potential for using home automation for energy savings and comfort improvements.
Home Automation Components
- Central controller which is an inelegant device connected with the whole system, its job is to manage, process, and control the home automation system, it can be a PIC microcontroller, PC ….etc.
- User interface in which user can control the home automation system and choose the mode he need in any appliance of the system, it can be a touch screen, GLCD, remote control…etc.
- Appliances which are the devices that controlled by the system and it can be any device such as clean machine, AC, lighting as a sub system…..etc.
- Connection which is the type of connection between systems and it can be wired or wireless.
Wired vs. Wireless Home Automation
The medium through which communications occurs is crucial to the feasibility of a home automation system. So the types of home automation systems are:
1. Wired System
Traditionally, wiring consists of wires that get snaked through the walls. There are three wired systems: electricity, telephone, TV cable. Which have been earned by the home automation and the user more agree with, because it is provide reliability, it connect each appliance with central controller, signal between sent between devices is travelling through a physical medium .
Wired system provide reliability, but it is difficult to install, and it not easy for error detection and resolving, unless there is a smart central device and advanced physical medium and connections.
2. Wireless System
Each appliance is connected with a device as a receiver or transmitter that depends on the function of the appliance and what does it need, and for each sensor there is a transmitter and receiver device.
Transmitter device send a signal such as RF signal and the receiver receives the signal moves it to an intelligent device which detects if the signal for the device that connected with, if yes the intelligent device makes the attached device to act the suitable action for the situation.
The main difference between wired and wireless system that the communication between system components and devices in wired system using physical medium, but in the wireless system the signal is generated as Radio wave signal -for example- travels on the air and cached by receivers.
Theoretical Back Ground
The Purpose of the Project
The main purpose of the home automation project briefly is to make life easier.
To achieve the main purpose we need to design a control system for home appliances, the user can control real loads by a single touch on the touch panel , away from the traditional bush buttons remote control the user will use his finger to select any option on the touch panel whether it is a on/off button or next/previous command.
The user can choose the right arrow to select between the appliances (light, door open, door close, heater) then he will use the on/off button to toggle the load status.
To achieve the goal of this project the touch screen must be chosen so it can be interfaced to the microcontroller (PIC microcontroller) , the resistive touch screen can be used since the microcontroller has it own build in analog to digital converter,
The microcontroller will convert the output of the touch screen to digital value (x-position ,y- position) then it will decide the press location on what button (the buttons is drawn on a graphical LCD which is under the touch screen ) so the user will feel as if he press the button itself
After this the microcontroller will execute a certain routine to toggle the corresponding load depending on the pressed button.
As shown in figure above we have proposed a block diagram to achieve the project goal, the configuration and the connection of each components can found in the datasheet, for example the datasheet of the GLCD and the touch screen requires the use of PIC microcontroller so both of them must be connected directly to the PIC in the appropriate way. Also the web site. http://www.mikroe.com/en/tools/ provides learning kits with a full document and schematic diagrams for those kits, which was an addition information source to know how we can use the graphical LCD and the touch screen
The real loads driver circuit will take the command signal from the microcontroller so it also it will be connected directly to the microcontroller,
Description of the main blocks
PIC microcontroller ,which will be the brain of the system
Why to use pic16f877A
At first any pic microcontroller that has portB and portD can be used to interface the graphical LCD, but since we will use a touch screen in the project and the output is analog voltage so we also need a pic microcontroller with a build in analog to digital converter, those specification can be found in the PIC16F877A
Graphical LCD idea and background
– Graphical LCD , at which the graphics will be displayed
The GLCD module is specially designed for microcontroller programmers who like an extra dimension in the projects.
This module has a 128 X 64 pixel graphical LCD with touch screen,
This LCD is controlled by KS0108 LCD controller via two segment drivers. LCD backlight color is yellow-green.
– Touch panel , which will respond to the touches and convert it to analog voltages.
– Driving circuit which will take the control signal from the microcontroller and drive a real 220V ac loads.
– interfacing circuit: this circuit will take the four wires from the touch screen and fed the microcontroller with the analog voltage (x,y)
4. Working plan
- first step is to buy the needed components
- start testing interfacing the components as follows
- connect the graphical LCD and display some pictures using the pic microcontroller
- connect the touch screen and test the output voltages when pressing on it, we will use the regular voltmeter to test the output voltages on each corner and it should be as follows
- design the output driving circuit to drive the real 220V loads by apply 1 5V on the input
- Software implementation
Since we are using a pic microcontroller then we need to use a compatible compiler and the easiest one is (MIKROBASIC) because it has a built in libraries for the graphical LCD also the used language is BASIC.
6. Why to use the mikrobasic instead of assembly (mp lab)
Using the graphical LCD in the project requires a lot o work in signaling the graphical lcd, so each picture or graph must be sent to the graphical lcd pixel by pixel which is a long work without any advantage because the mikroelctronica compiler (mikrobasic) comes with a built in libraries that support both (LCD, and graphical LCD) so the time needed for doing the libraries can be used to add more features to the main project.
MikroBasic allows the user to quickly develop and deploy complex applications:
- Write the BASIC source code using the built-in Code Editor (Code and Parameter Assistants, Syntax Highlighting, Auto Correct, Code Templates, and moreâ€¦)
- Use the included mikroBasic libraries to dramatically speed up the development: data acquisition, memory, displays, conversions, communicationsâ€¦ Practically all P12, P16, and P18 chips are supported.
- Can be used to Monitor the program structure, variables, and functions in the Code Explorer.
- Inspect program flow and debug executable logic with the integrated Debugger.
- Get detailed reports and graphs: RAM and ROM map, code statistics, assembly listing, calling tree, and moreâ€¦
Introduction to Project Management
For planning any project, you must manage it. The whole project is divided into three major elements: tasks, resource and time. Each element’s work affects the others, means they are related.
Means what each piece of project component will achieve and the hardware connection between these components, some tasks may include:
- Programming Microcontroller.
- User interface â€œGLCDâ€.
- Project documentation.
Means anything used to achieve the goals of project, which can be:
- People as who has experience with the home automation they can be users or experts.
- Machinery which used to develop the project components.
1.5 System Requirements
1.5.1 System Hardware
- Micro controller (PIC): to control the whole system.
- Graphical LCD: as the user interface.
- Driving CKT: to connect loads with the PIC.
1.5.2 System software
- Micro Basic for programming PIC.
- Following chapters will be more detailed for each part.