Week -2

Aim:-

1. To generate a simulink model of a doorbell using a solenoid.

2. Use a thermistor to sense the temperature of a heater & turn on or turn off the fan

Simulink Model :-

1. Door Bell

a. Pulse Generator is used to create square pulse at a regular intervals.

b. Battery is used to provide a constant voltage source to a solenoid.

c. After applying the voltage in the circuit, then solenoid changes its position linearly.

d. Change in position of the solenoid is then sensed by the Ideal translational Sensor, which is connected in the circuit.

e. Scope is used in the circuit to obtain the result while voltage is applied in the circuit

Graph of Doorbell :-

Thermister :-

Given Conditions :-

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

b. Fan will be ON if the temperature above 25 °C, OFF otherwise.

Simulink :-

a. From 0 to 10 Sec, Fan will be off, because temperature is below 23 Deg C or 293 k.

b. From 10 to 30 Sec, Fan will be switched On, because temperature is above 27 Deg. C or 300 k.

c. From 30 to 50 Sec, Fan will be off, because temperature is below 23 Deg C or 296 k.

d. We have used a signal builder in this circuit, to provide the signal in the form of temperature and time to the thermistor.

e. Voltage sensor is placed parellel to the resistor and in series to the thermistor with DC voltage source of 12V in the circuit.

f. Threshold value is calculated.

g. Above threshold value is then applied to the universal motor and according to that the rotational position sensor is used to sense the position of the fan.

Graph :-

Conclusion:-

Hence the conditions are evaluated