Driveway Alarm / Vehicle detection
After extensive googling i found others who had successfully used a HMC5883 magnetometer/compass to detect metal vehicles - AKA cars.
The use cases are around car parking (detect when car space is free) and car counting (counting number of cars that use a road).
I would really like to use this HMC5883 sensor to detect a car moving past the sensor, to act as a cheap driveway alarm.
I am hoping to use a battery powered node for this, and i think a big induction is too power hungry loop and i would like to avoid digging and placing a sensors in the road.
Existing driveway alarms seem to use a (magnetic field change?) probe to detect a car, but i cant find just the probe available, and kits are quite expensive and defeat the point of MySensors - DIY!!
The HMC5883 solution would be low power and i could maybe get away with the sensor/node beside the road and not underneath it.
I discovered this: https://gitlab.com/ColoradoSchoolOfMines/parking_sensor/commit/cca7b040654297fd06bc806e0ca8cef844f8d456
which works - serial prints CAR in or CAR OUT when a car moves past the sensor.
I tried to blend the above sketch with a MySensors sketch (and failed) - the gitlab code is way over my head and i think it uses memory that MYS also uses....
Has anyone played with the HMC5883 for a similar purpose?
@fleinze can you please share your code from your "Fun with magnetometer / digital compass sensors" post?
Anyone else interested in this car detection idea?
Maybe you could use an ultrasonic distance sensor to detect if anything is in its measuring range?
If you did not yet buy that chip: According to SparkFun, that sensor is retired. But they do suggest alternatives.
I am not sure if that's SparkFuns definition or Honeywell