14-08-2012, 11:05 AM
automatic window shade with temp sensor
automatic window shade with temp sensor.docx (Size: 828.64 KB / Downloads: 48)
INTRODUCTION:
In an extremely mechanized world such as today’s it is necessary to make our life better, convertible and economical. This is the purpose for which the intelligent house is developed.
Intelligent house consists of two microcontroller based major units, one unit for outside the house other for inside the house. Both units are further divided into sub unit as.
Self-Adjusting Window Shade
The self adjusting window shade will automatically raise, lower, open, and close your blinds by itself. A computer terminal acts as a remote to broadcast instructions to the window shade via RF. These manual adjustments are stored into the microcontroller’s system along with the room’s current ambient light and temperature settings. When these lighting and temperature conditions are found in the room, the window shade will automatically readjust itself to that previous level.
Advance counter
We utilize two A & B IR based sensor used to count total person in the room. If someone enters in the room AB sensor get activated. In case of leaving BA sensor get activated.
Fire alarm:
In case of fire, circuit automatically detect temperature of office and activate water pump to control it.
The idea of the motorized window shade is a hi-tech concept, has already been implemented by several companies such as Lutron and Draper. However, none of these companies has implemented a memory system that would allow the window shade to operate independent of human control.
The blinds are moved up and down using DC motors. The PWM based DC motors are used because of their accuracy since the blinds are expected to stop at specific positions depending on the user's previous preferences. They both drive a single gear that increases the torque in the system, allowing shades to be raised smoothly. Spools are used to roll up the string that holds the window shade. Pulleys are used to redirect the force of the pulling so that the single gear and rod are able to raise and lower the shade. The string goes through the holes of the original window shade frame, so that its outside appearance looks exactly like a normal window shade.
Form circuit point of view we have connected an LRD (light dependent resister) in the room. The output from LDR is an analog signal, which is converted into digital form using special feature of our PIC microcontroller i.e. having inbuilt Analog to digital converter. The DC motor is used to control the position of the window blind.
So our system continuously scan the intensity of light available in the room. IF light intensity is below the certain limit it start opening the window blind, after opening the blind completely if light intensity is still low, system power on the light in the room. So our system also acts as power saver.
The counter is used to display total number of person inside the house. One of the most important question is that how can IR based sensor sense that person is coming inside the room or going outside the room. To solve this problem I have used two IR receivers A and B. The sensor A is connected to pin No-28 and sensor B is connected to Pin No-27 of microcontroller. The sensor A is situated just outside the gate and sensor B is situated just inside the gate. So whenever we enter the room we cut first outside sensor A and then inside sensor B. So in case of AB microcontroller increment counter. When we exit the room we cut first Sensor B and then sensor A. In case of BA microcontroller decrement the counter.
AB=Entering house=Increment reading
BA=Exiting house=Decrement reading
PRINCIPLE OF AUTOMATIC WINDOW SHADE WITH TEMP. SENSOR:
The idea of the motorized window shade is a hi-tech concept, has already been implemented by several companies such as Lutron and Draper. However, none of these companies has implemented a memory system that would allow the window shade to operate independent of human control.
The blinds are moved up and down using DC motors. The PWM based DC motors are used because of their accuracy since the blinds are expected to stop at specific positions depending on the user's previous preferences. They both drive a single gear that increases the torque in the system, allowing shades to be raised smoothly. Spools are used to roll up the string that holds the window shade. Pulleys are used to redirect the force of the pulling so that the single gear and rod are able to raise and lower the shade. The string goes through the holes of the original window shade frame, so that its outside appearance looks exactly like a normal window shade.
Form circuit point of view we have connected an LRD (light dependent resister) in the room. The output from LDR is an analog signal, which is converted into digital form using special feature of our PIC microcontroller i.e. having inbuilt Analog to digital converter. The DC motor is used to control the position of the window blind.
So our system continuously scan the intensity of light available in the room. IF light intensity is below the certain limit it start opening the window blind, after opening the blind completely if light intensity is still low, system power on the light in the room. So our system also acts as power saver.