Week -2

1. For the door bell

The designing goes as follows:

• We use pluse generator, which follows a squared sine wave pulses. Which indicates the ON and OFF mechanism.
• We then connect it to the switch and state the threshold, above which the switch turns ON.
• When the switch is ON then there is a current flow and a voltage difference can be seen.
• This then triggers the mechanical motion sensor, which is controlled by solenoid block.
• Whenever the switch is ON, then the there is some motion and hence the mechanical sensor now gives the output.

2. Thermistor problem

As stated, we given the required input condition to the signal builder block

• The Signal builder block is connected to the controlled temperature source, which helps in maintaining the temp difference regardless of the inlet heat flow rate.
• This is then connected to the thermistor, which senses the change in temperature and then this causes the voltage to vary across the battery.
• This variation is sensed by the voltage sensor and then it is directed to the switch (where again a certain threshold is given) and according to the threshold values the input varies between two variables.
• With this we can see the switch is turned ON only for above 25 degree celcius. which can be seen in the graph clearly.
  • That is even though the temperature at 30 sec and 50 sec is 23 degree celcius, the fan remains OFF, which satisfies the given condition.

Please check all the files attached