In the designed system, the test and flow measurements continued
until the steady state infiltration rate was reached. This usually happens
after 1 to 2 h in most soils (Maheshwari, 1996). The systemstopsworkingwhenever
the infiltration rate changes are less than 10% for an interval
of 30 min (Amer, 2011). This is done by comparing the maximum
and minimum values of the infiltration rates recorded every second in
the last 30 min of the test. The test is terminated whenever the difference
is not exceeding 10%.
The Arduino code loaded to the Arduino board from computer and
stored on it for later use of the system. The set-up with continuous
water level sensor could be also applied to run a single ring infiltrometer
with falling headmethod (using only the inner ring). This could be done
by simply adopting the code to turn on the pump after full seepage of
water and turn it off when the required height was reached.
Besides the cost effective final price of the proposed system, it has
the following advantages compared to previous proposed automating
systems:
• Unlike some of the proposed systems, the current systemdoes not require
using a laptop computer in the field. In the current set-up, the
digital data of the water flow are stored in a real-time on a micro-SD