MARB will be equipped with a bunch of sensors to sense time, humidity, temperature, barometric pressure, ambient light, gas concentration, orientation and acceleration. So far I have tested a DHT11 based hygrometer, a TEMT6000 ambient light sensor and a MiCS-5524 based gas sensor.

The gas sensor can easily detect an open bottle of ammonia solution.

Testing a DS1302 RTC breakout from Sunfounder:

After tinkering a while with many different sensors, I decided to use for now following sensors:

• DHT11 breakout humidity sensor 20-80% (5% accuracy)
• BMP180 breakout barometric pressure sensor (300-1100 hPa, 0.03 hPa resolution)
• Dallas 18B20 breakout temperature sensor (-55 to +125 °C)
• TEMT6000 breakout light sensor (illumination Range: 1 – 1000 Lux, spectral response closely emulates human eye)
• DS3231 precision RTC breakout
• MiCS5524 CO, alcohol and VOC gas sensor breakout
• LSM303DLHC compass and accelerometer breakout

Resulting sensor module design:

3-D printed part in the mail:

Sensors assembled: