Week -2

objective 1:- Make a Simulink model of Doorbell using solenoid block with the following details: 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.

model:-

block use:-

signal generator, scope, battery, switch, solenoid, ideal transnational motion sensor, mechanical transnational refrence, electrical refrence, solver configuration, simulink ps converter, ps simulink converter.

result:-

door bell

solenoid

model explaination:-

the above parameters are of signal generator, this model run time is for 20 sec, so doorbell graph shows that in every 2 sec amplitude will be 1, switch will be closed solenoid will get pickup & doorbell will operate. their are 5 cycle for 20 sec run time. when amplitude is zero switch will get off, solenoid will get off.

objective 2:-Use a thermistor to sense the temperature of a heater & turn on or turn off the fan as per 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.

model:-

block use:-

signal builder, scope, simulink ps converter, ps simulink converter, controlled temperature source, thermistor, battery, resistor, switch, constant, voltage source, electrical refrence, thermal refrence, solver configuration.

result:-

temperature vs time

voltage vs time

switch operate with time (1-on, 0-off)

model explaination:-

temperature is converted from celcius to kelvin. 293 k from 0 to 10 seconds, 300 k from 10 to 30 seconds, 296 k from 30 to 50 seconds.

build signal(temp. vs time) as above as per given condition in signal builder block , using axes option in signal builder, change time range.

graph 1 shows temp. vs time , 293 k from 0 to 10 seconds, 300 k from 10 to 30 seconds, 296 k from 30 to 50 seconds.

graph 2 shows voltage across resistor with respect to time. when fan is on from 10-30 sec voltage is 0.01286.

graph 3 shows switch operation, in 10-30 sec switch gets on(1) as temp. is 300k which is greater than 298k (25*c) , otherwise switch get off(0).