Week -2
Simulink model of Doorbell using solenoid block:
1. When the switch is closed the electromagnet receives electrical power from the battery and pulls the metal arm to hit the bell producing sound.
2. Switch is closed for 2 seconds and then released for 2 seconds. this is done several times.
3. Physical movement of the plunger is observed and graph is plotted for the position of plunger.
Steps:
1. A pulse is generated having amplitude s 1 and T(on) = 2 sec and T(off) = 2 sec.
2. it is fed to simulink to physical system converter then to switch.
3. The switch is connected to a battery, a solenoid, a resistance and the circuit is grounded.
4. 'R' is the Mechanical translational conserving port, connected to 'R'(positive probe) of Ideal translational motion sensor.
5. The C port of both the components is grounded.
6. A solver configuration is attached to the electric circuit.
Signal input graph:
Plunger input graph:
Result:
1. The plunger gets attracted towards the solenoid as it becomes temporarily magnetically charged for 2 seconds.
2. After it loses the charge, the plunger is on freefall and oscillates about its original position for some time and rests.
3. The same process repeats as the solenoid is charged again.
THERMISTOR
Steps:
1. a signal builder is used to generate the specified signal. the signal is converted into physical input.
2. it is then passed on to the controlled temperature source connected to the thermistor.
3. Thermistor is connected to a DC voltage battery and a current sensor.
4. the circuit is connected to solver configuration.
5. the output of current sensor is fed to switch.
Working:
When the temperature is above 25 degree Celsius, the output is 1 and the fan is ON. This happens in time 10 to 30 sec. the threshold for the switch is taken as 5*10^(-12) as calculated by the current sensor.
Input signal:
current in circuit:
output (ON and OFF) for fan:
Result:
Therefore we can see the fan is ON in between 10 to 30 seconds(temperature more than 25 degree celsius) and otherwise closed, according to the problem statement statement.
both the simulink files are in this link"
solenoid_doorbell: https://drive.google.com/file/d/1rSqzlgmz5p3ebwt_NMwEeOoWqzJzSWNL/view?usp=sharing
thermistor: https://drive.google.com/file/d/1txSsINeBqoaOA14nBpSYw3SI_cgYC07o/view?usp=sharing