A hygrometer is an instrument used for measuring the moisture content in the environment. Humidity measurement instruments usually rely on measurements of some other quantity such as temperature, pressure, mass or a mechanical or electrical change in a substance as moisture is absorbed. By calibration and calculation, these measured quantities can lead to a measurement of humidity.
like hygrometer we amke lend humidity detector which checks the humidity in lend and the given the water to that lend
it mechine is totally automatic
in that we save the distence between to plants and then it move in 'x' and 'y' both axis..
by this concept we save water.