Introduction: Home Health Sensor

About: Test 1.. 2.. 3..

Hi all,

Hope you're all doing well. As mentioned earlier I was to post a home health sensor in one of my previous instructable. So here it is:

Wearable technology does a fine job of keeping tabs on your personal fitness. But to measure the health of the place where you live, you need a different tool. This device monitors the temperature, humidity, noise, and light level for any room and can also act as a intrusion detector, a flashlight and charge phones and use the 1W LED for creating a stroboscopic effect to get intruders out. Within the casing, a collection of sensors sends information to an Arduino, which interprets the input and displays the data on a small OLED screen. Based on the device’s readings, you can turn on a dehumidifier, lower the thermostat, or crack open a window—whatever it takes to keep your home environment comfortable.

This Device does the following:-

  1. Measure and Display Temperature(in *C or *F).
  2. Measure and Display Humidity(in %).
  3. Calculate and Display Feels Like(Heat Index)(in *C or *F).
  4. Measure and Display Sound(in dB).
  5. Measure and Display Light(in lux)(1 lux = 1 lumen/m^2).
  6. Measure and Display Distance from a particular object.(in cm or inch).
  7. Used as a intrusion detector(a separate siren can be added).
  8. Used to generate stroboscopic effect.(to scare off intruders and for parties)
  9. Use as a flashlight.
  10. Charge phones in emergency.

I'd like to mention that this instructable is posted early because of the last date of pocket sized contest. Hence the instructable is still not complete. This device can give all sensor readings but cannot be yet used as a intrusion detector and flashlight as I am still writing code for a User Interface(UI) with push buttons. So please vote for me at least in the pocket sized contest as I continue working for the code and you guys gather parts and start calibrating the sensors. You may later vote me in the Arduino contest as you wish(If you like the project).

Also please do not skip steps if you want the project to be error free(many people comment about not working projects and have not installed Arduino libraries properly leading to problems). Or you may skip some first steps on sensor calibration and start with mic and light calibration.

So let's gather parts and get started:

Step 1: Gather Parts:

Parts List:-

  1. Arduino Mega/Uno/Nano (For checking Sensors)
  2. Arduino Pro Mini
  3. Programmer for Pro Mini(You can use other Arduinos as well)
  4. OLED Display (Type SSD1306)
  5. LDR + 5kΩ(I used 3x 15kΩ in Parallel) OR TEMT6000
  6. 3x Push Buttons
  7. Slide Switch
  8. Red LED
  9. DHT22/DHT11 Temperature Humidity Sensor(Use depending on your requirements)
  10. Li Poly Battery with 5V step up and Li Po Charger.
  11. 1W LED with 100Ω(or near)
  12. Raspberry Pi Case(If you have 3D Printer you can make one. I just don't have one around.)
  13. Condenser MIC with amplifier circuit(Mentioned later) OR ADMP401/INMP401
  14. Jumper cables(mostly F-F,M-M good to have some F-M also)
  15. Rainbow Cable or Multi-strand Wires
  16. USB B OR USB B mini(depends on the type of Arduino)
  17. Breadboard (for temporary connections, for calibrating sensors)


  1. Soldering iron or station
  2. Solder
  3. Solder Wax
  4. Tip Cleaner...(Anything else required for soldering can be added..)
  5. Glue Gun with Sticks(Oh well.. glue sticks)
  6. Hobby knife (not required as such, just to remove some plastic parts of RPI Case to get more space and to make holes for LEDs, push buttons and LDR. You can use other tools as well.)

Step 2: Test HC-SR04 Ultrasonic Sensor

First let's test HC-SR04 if it's working properly or not.

1. Connections:

Arduino HC-SR04





2. Open the attached .ino file and upload the code to Arduino board.

3. After uploading place a ruler beside the sensor and place object and check readings in the serial monitor(ctrl+shift+m). If the readings are almost OK, we can proceed to the next step. For troubleshooting go here. For additional information visit here.

Step 3: Test DHT11/DHT22 Sensor:

Now let's proceed to test the DHT11/DHT22 sensor.

1. Connection

Arduino DHT11/DHT22

VCC______Pin 1

D2________Pin 2 (also connect to Pin 1 via 10k resistor)

GND______Pin 4

Note: In case you have a shield directly connect signal pin to D2 of Arduino.

2. Install DHT Library from here and Adafruit_sensor library from here.

3. Open .ino file from examples of DHT sensor library, edit the code as per the instructions(DHT11/22) and upload code to Arduino board.

4. Open Serial Monitor (ctrl+shift+M) and check readings. If they are satisfactory, continue to next step.

Else check here for more.

Step 4: Calibrate LDR or TEMT6000:

Let's go further to calibrate LDR/TEMT6000:

To calibrate LDR you can go here. You have to have or borrow a luxmeter for calibration.

For TEMT6000 you can download the .ino file for Arduino code.

1. Connections:





2. Upload the sketch to the Arduino and open Serial Monitor. Check the readings with respect to a luxmeter.

3. If everything's fine we can proceed.

Step 5: Calibrate Condenser MIC/ADMP401(INMP401):

Finally the last one. The condenser microphone or ADMP401(INMP401). I'd recommend going for ADMP401 as the board size is small. Else you may go here for the condenser microphone and it mostly will take more space in the case.

For ADMP401: (note: I have yet to calibrate the sensor to show dB values. You will only see ADC values.)

1. Connections:





2. Upload the sketch to the Arduino. Open Serial Monitor. Check readings. Reading is high in high volumes and low in low volumes.

Step 6: Bring It Together:

Finally it's time to bring it together.

  1. Join everything as per the connections on a breadboard.
  2. Install the libraries. Links in .ino file.
  3. Upload it to the Arduino.
  4. Check if everything is fine and shows correct readings.
  5. If it's all good we can finally assemble it in a case.

Note: This step is still incomplete as the code is not yet final. There will be a added UI in the next version.

Step 7: Put It All Into a Case:

Time to put it all into a case:

  1. Program the pro mini.(You can google it how to do it)
  2. Plan how would all the sensors, display, Arduino, battery and charger will fit in the case.
  3. Use plenty(not too much) of hot glue to secure everything in place.
  4. Wire everything

I'm sorry I didn't include any images to help you as I still have to make some changes in the code.

Step 8: Testing of Final Device and Final Thoughts:

Here we go... We created a small device which can do so many things. The device is not yet completed and will require some time to create the final one. I'd like you to vote for me in the contests to motivate me to go forward to complete the project. Thanks for your votes and likes and I'll see you soon with the completed project with more pictures and videos of the project. And of course final assembly

Pocket Sized Contest

Participated in the
Pocket Sized Contest