Week -2

Aim:1 To make simulik model fr dooarbell

2 To use thermoster yo sense temperature of heater and turn on/off the fan

DOOR BELL:

Simulink and model explanation:

FOLLOWING BLOCK IS USED-

1. PULSE GENERATOR
2. SWITCH
3. BATTERY
4. SOLENOID
5. IDEAL TRANSLATIONAL MODEL
6. MECHANICAL TRANSALTIONAL MODEL
7. ELECTRICAL REFERENCE
8. SCOPE

As per given condition switch closed for 2 sec. then released.

• Solenoid blockset is term for coil of wire used as electro magnet .it creats magnetuc field from elctric curentand uses it to create linear motion ,commanly used as to power a switch like starter in automobile .
• A battery is connected to voltage supply
• switch is placed in between the battery and solenoid valve to cater for provided condition here and SPST switch is used there are difficult type of switches availabel as requirement
• and seprate input signal is provided forclosing and opening the switch ,if external control signal is greater than the threshold value of switch ,switch get cosed, and external signal are provided with a pulse generator block with peroid 4 sec. and pulse width is 50 % of time period .
• to sense the movement of the plunger an ideal translational motion sensor is connected to it

BLOCK DIAGRAM : DOOR BELL -

pulse generator used to create the squre wave pulses at regular interval .switch block is controled by external physical signal and if the external physical signal is greater than tge switch is closed or open .

RESULT:

conclusion of door bell: giving input for 2 sec. in the pulse generator to open and close the switch ,when switch is closed the solenoid block recieves electrical power from battery and plunger mooves from port r to c to hit the bell and sound produce,physical moovement of plunger is observed by using transalational motion sensor and physical output converted into simulink out put model displayed in the scope .

Thermister:

Temperature source: 20 °C from 0 to 10 seconds, 27 °C from 10 to 30 seconds, 23 °C from 30 to 50 seconds

Fan conditions: ON if the temperature above 25 °C, OFF otherwise

Explanation:

signal block building is added to to input the values as per given condition .

at point 1 time=0 sec. to 10 sec and temp, range is 293k

at point 2 time = 10 sec. to 30 sec. and temp=300k

at point 3 time=30 sec. to 50 sec. and temp= 296k.

Thermister is type of resister whose resistance is based upoun the temperature .A linear resister is used to control the amount current from battery. voltage sensor used to conert voltage measured between two point

thermister signal builder:

BLOCK DIAGRAM: THERMISTER

RESULT:

from 0-10 sec fan is off cause of temp. is 293k

which is below the temp. 298k after 10sec it goes to 300 k so fan will turn on after 30 sec fan is off deu to temp. goes 296k less than 298k.