Week -2

Project name - Make a Simulink model of Doorbell using solenoid block

Below is the Simulink model for Doorbell using solenoid block.

Above model, i have used Pulse generator, Switch, Battery, Solenoid, ideal Translational motion sensor, Mechanical translational reference, electrical reference & Scope.

As per the condition given in the problem, a switch is closed for 2 sec & after opened.

Here pulse gen bock is used for generating the pulses for a desired time interval.

as shown is main simulink diagram, connection are attached. & received below results.

Output of the pulse gen given to switch to ON & OFF the operation of the switch. When switch getting pulses from pulse gen it gets closed and battery connected to solenoid coil. After it will get energised & attract the plunger and bell generating the sound.

For this movements we used translational motion sensor & as usual physical I/O converted using PS converter and outputs got in scope.

2nd Problem -

Project name - thermistor to sense the temperature of a heater & turn on or turn off the fan

Below is the Simulink model for thermistor to sense the temperature of a heater & turn on or turn off the fan.

as per the problem given,

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 is above 25 °C, OFF otherwise.

converted Temp Degree Celsius to Kelvin to add data in Signal Builder.

So for condition 1, 0 sec to 10-sec temp will be 293.15K

Condition 2, 10 Sec to 30 Sec temp will be 300.15K

Condition 3, 30 Sec to 50 Sec temp will be 298.15k

As shown in the above Simulink model Temperature source created heat is sensed by thermistor.

One end of the thermistor is connected to the battery, and another to the resistor. So change in temp will change the current flowing through the resistor. And will result in voltage drop across the resistor. Change in voltage is sensed by the voltage sensor. By connecting the Simulink to the physical converter signals are connected to the switch.

The voltage threshold value to the switch to start Load (motor) & switch will be closed it crosses the peak value (297).

as per the condition given,

condition 1, 0 sec to 10-sec temp will be 293.15K = Motor will be OFF

Condition 2, 10 Sec to 30 Sec temp will be 300.15K = Motor will be ON as crossing threshold

Condition 3, 30 Sec to 50 Sec temp will be 298.15k = Motor will be OFF as again coming below threshold.