Wednesday, 8th October

Manage to make temperature sensor working at 3 different zone: hot, cold, normal
materials:
10K thermistor
10k resistor
*build in Voltage divider circuit form*

Parameters:
Vout <> low voltage caused by low resistance thus high temperature -> red LED on
Vout >2.2V and <2.5v> normal resistance (7900-10000), normal room temperature ->green on
Vout >2.5V -> high voltage out caused by high resistance thus low temperature ->2 LEDs on

Problem encountered:
when either one of the LED is on (thus in normal or high temperature), the LED light up very dimly that we can hardly observe its light. When both LED on (thus cold, low temperature, hi-resistance) they can light up very brightly.

Solution:
still not known. Might ask the GA tomorrow. Another possible way is to use LM35DZ (Centigrade temperature sensor) which is better and more controllable than using voltage divider circuit. LM35DZ gives 0.5mV output voltage for every 1 degree Celcius.

LDR: Lighting sensor
Lighting sensor will be used to lit up baby incubator at night or when lighting is low.

materials:
LDR
37K (since LDR resistance is very high, we need highter resistor to control the voltage swing better)

LCD: havent implemented
used to tell parents and nurse about baby's profile and condition

Fan control: havent implemented
Fan control is a responsive action when temperature in baby box is too high.

RF Wireless: maybe used to send baby data to nurse but havent implemented. maybe used for emergency alarm (such as turning on the buzzer). Immediate reminder. Baby's sound sensor to quickly alert the nurse about what happen with the baby.