Week -2
- Make a Simulink model of Doorbell using solenoid block with the following details:
In the above arrangement, when the switch is closed the electromagnet receives electrical power from the battery and pulls the metal arm to hit the bell producing sound.
Create a situation where the switch is closed for 2 seconds and then released. Observe the physical movement of the plunger.
Assume remaining parameters.
Answer:
Full simulation with all the simscape and Simulink block System.
Working:
When the circuit is closed, the plunger pulls the metal arm to hit the bell.
A Pulse Signal Generator is used to turn the signal switch ON/OFF.
Transalation sensor is used to capture Plunger Position.
Input Signal of the Pulse Generator:
Solenoid Properties:
Output:
Results:
The solenoid's damping effect is pulling the plunger back to its mean position after the input signal is switched on.
The voltage input of the solenoid should match that of battery, therefore the 12V input is given.
https://drive.google.com/file/d/1B0uET6oV7MGrN_2stsmXiGkelULVSBi2/view?usp=drivesdk
2. Use a thermistor to sense the temperature of a heater & turn on or turn off the fan as per the below conditions:
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
OUTPUT:
INPUT SIGNAL :
WORKING:
The input signal as shown above. The Thermistor takes the above signal and runs using the electric circuit connected. A voltage drop is observed at the thermistor, and cosequent voltage rise in the resistor when the input temperature is increased. Given below is the voltage spike across resistor.
The voltage drop value is input to the Switch in the Mechanical Circuit. The Threshod is set to 0.012V. Whenever the input voltage drop crosses this threshold the swittch is closed. when the switch is closed, a Controlled Voltage Source is started and drives the DC Motor. The Motor is connected to an Ideal Rotational Motion Sensor to capture the Fan RPM. Below is the result of the Fan RPM as a function of time, confirming that the fan is switched on when the temperature is above the given thresold.
RESULT:
Successfully simulted an automatic fan simulunk.
The fan is switched ON when the thermistor temperature is above threshold.