It is common to see a baby sleeping outside in winter time in Scandinavian countries, it is part of the culture.
Attaching this system to the pram and monitors different variables like: temperature, sound, acceleration, light, etc in order to see the status of our baby wherever he is (at our garden, balcony, kindergarten, on a trip with the nanny).
ThingSpeak IoT cloud was using to visualize the data capture by the sensors as can be seen in the following picture and also in the public channel:
Sound: Inverted Op Amp with gain 47 connected to ADC A2.
Accelerometer: It is connected to ADC A4, A5 and A6. An RC low pass filter is filtering to the outputs. MMA7260 Sleep mode is manage by Genuino pin 7.
Thermometer: LM92 provides the information by I2C bus with 1K pull up resistors.
Photocell: Connected to A1 by a divider resistor fed by pin 6.
Power: All circuit are 3.3V. A portable charger provides the 5V for Genuino MKR1000.
Serial Monitor debugging:
As can be seen in the source code, the sensors values are coma separated printed in order to see the real time sensors output changes.
Some good improvements are listed below:
Data analysis: This system is just monitoring, would be nice to analyze the data, take decisions, and inform by different levels alerts.
Sound: Add a next amp stage and filter to have a more sensitive detector and a clean signal.
More sensors: UV level and GPS.