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Enabling better global research outcomes in soil, plant & environmental monitoring.

AIM Automatic Infiltration Meter

The AIM1 Automatic Infiltration Meter is a stand-alone logging instrument for the measurement of infiltration rates with the tension infiltrometer.

The AIM1 Automatic Infiltration Meter is a convenient solution for infiltration measurements that saves researchers time. The AIM relieves researchers of the need to manually monitor their Infiltrometer with a stop-watch and notepad.

The AIM1 automatically collects infiltration data from a Tension Infiltrometer. Converted and unconverted data is stored within the AIM and can be downloaded as a csv file for further data manipulation and analysis. The AIM can support up to two Tension Infiltrometers or your own Infiltrometer/Permeameter with installation advice from ICT International.

The AIM1 is a fully self-contained unit with 4GB data logging capacity and an internal battery that will last several days’ field work. The battery is easily recharged with a 24V power supply (CH24). Communication is via a USB port or wireless connectivity. The AIM is IP-65 rated and has a Windows and Mac compatible Graphical User Interface.

Infiltrometer Specifications

20cm Model 8cm Model
Specifications US Patent No. 4884436 US Patent No. 4884436
Diameter Disk 20cm 8cm
Inside Diameter Water Reservoir 5.1cm 2.54cm
Inside Diameter Bubbling Tower 2.54cm 2.54cm
Length Water Reservoir 81cm 81cm
Bubbling Pressure Membrane 30cm H2O 30cm H2O
Carrying Case Dimensions (optional) 28cm x 36cm x 107cm 28cm x 36cm x107cm
Pressure Transducer 1 psi (67cm H2O) 1 psi (67cm H2O)

Instrument Logging

Analogue Channels 5 differential
Resolution 0.00001V—24-Bit
Accuracy 0.001V
Minimum Logging Interval 1 second
Delayed Start Suspend Logging, Customised Intervals
Sampling Frequency 10Hz
Communications USB, Wireless Radio Frequency 2.4 GHz
Data Storage MicroSD Card, SD, SDHC & SDXC Compatible (FAT32 format)
Software Compatibility Windows 7, 8, 8.1 & 10. Mac OS X.
Data Compatibility FAT32 compatible for direct exchange of SD card with any Windows PC
Data File Format Comma Separated Values (CSV) for compatibility with all software programs
Memory Capacity Up to 16GB, 4GB MicroSD card included.
Temperature Range -40°C to +80°C
R/H Range 0-100%
Upgradeable User Upgradeable firmware using USB boot strap loader function

POWER

Internal Battery Specifications
960mAh Lithium Polymer, 4.20 Volts fully charged
External Power Requirements
Bus Power 8-30 Volts DC, non-polarised, current draw is 190mA maximum at 17 volts per logger
USB Power 5 Volts DC
Internal Charge Rate
Bus Power 60mA – 200mA Variable internal charge rate, maximum charge rate of 200mA active when the external voltage rises above 16 Volts DC
USB Power 100mA fixed charge rate
Internal Power Management
Fully Charged Battery 4.20 Volts
Low Power Mode 3.60 Volts – Instrument ceases to take measurements
Discharged Battery 2.90 Volts – Instrument automatically switches off at and below this voltage when no external power connected.
Battery Life varies
Example A: With a recommended solar panel and/or recommended power source connected, operation can be continuous.
Example B: Power consumption is dependent on number and type of sensors connected, frequency of measurement and measurement duration

How It Works – Example field installation

aim-dia-01
  • A Tension Infiltrometer is installed in the field and made ready for measurements as per the recommended methodology.
  • A differential pressure transducer (CL030) is installed near the bottom of the Infiltrometer and is inserted in the tubing between the top of the water tower and the bottom of the water tower. The use of a differential transducer in this way helps to eliminate the effects of bubble noise in the measurements. Figure 1 is an example of an automated Infiltrometer field setup logging two devices at the same time.
  • The pressure transducer is connected to the AIM Automatic Infiltration Meter. The transducer will output a value relative to pressure difference between the air pressure at the top of the water tower and the water pressure at the bottom of the water tower. The pressure value recorded by the transducer is linearly related to a metric value displayed on the Infiltrometer. The AIM converts the pressure value recorded by the CL030 to a metric value.
  • The researcher assigns a logging interval in the AIM. For sandy soils logging intervals can be measured in seconds. For clay soils logging intervals can be measured in minutes.
  • Figure 2 is an example output data for the CL030 pressure transducer versus time from a Tension Infiltrometer.
  • Figure 3 is the data from Figure 2 converted to cumulative infiltration and presented as a function of the square root of time. Output files can record millivolt data, cumulative infiltration data, or both.

aim-fig2-fig3-01

More Details

  • The AIM1 is a fully self-contained unit requiring power input from a solar panel (field applications) or 24V power supply (glasshouse applications).
  • All data is stored within the unit on a removable MicroSD card.
  • Communication with the AIM1 is made either by USB or wireless connection.
  • In conjunction with an ICT web-based controller, the AIM1 and/or individual sensors can be controlled remotely. Real-time, live measurements can be made remotely from any location with internet access.
  • The AIM1 is compatible with the ICT Combined Instrument Software. The software is GUI based and extremely user-friendly. This software allows complete control of the AIM1 such as real-time measurements, data logging settings, diagnostics and sensor configuration.
  • The AIM1 has a 2 wire, non-polarised bus for power supply. There is no chance of incorrect wiring of positive and negative voltage because the AIM1 is non-polarised.
  • The AIM1 has an internal lithium polymer battery that is kept charged by an external power supply (solar panel or mains DC power supply).
  • The AIM1 is IP-65 rated and has been demonstrated to operate in extreme environmental conditions. Units are being used in diverse environments from hot Australian deserts, tropical Amazon rainforests, temperate German forests, Indian agricultural fields and North American Arctic cold.

AIM Instrument

  • Automatic conversion of pressure transducer measurements to cumulative infiltration
  • Up to 4 x pressure transducers per AIM

Logging:

  • Stand-alone logging
  • 4GB MicroSD Removable Storage Card (capacity: 10+ years data storage)
  • Wireless connectivity and data transfer
  • Simple conversion and scripting
  • Flexible sensor calibration, look-up tables, and user scripts
  • 24-Bit resolution
  • IP65 rated water proof enclosure
  • Free Windows utility configuration software
  • Optional wireless logging

Power management:

  • Field: direct connected solar panel
  • Lab: mains DC power supply
  • Internal Lithium-Polymer battery
  • Internal Lithium-Polymer battery charger and power management
  • Optical isolation lightning protection
  • CH24 - 24 Volt Power Supply
    The CH24 is a 100 - 240Volts AC Mains to 24Volts DC power supply adapter; capable of outputting up to 2.5Amps. For most ICT Instruments.
  • MCC Mini
    The MCC Mini is a simple to use USB Serial to Radio Communications device providing a high level of integrity in data transfers. Its miniature design and minimalist approach make it an attractive solution for portable computers and less intrusive workstation setups where space and weight are of concern.
  • Tension Infiltrometer
    Tension infiltrometer with 20 cm diameter baseplate.

Ankeny, M.D., Ahmed, M., Kaspar, T.C. and Horton, R. 1991, ‘Simple Field Method for Determining Unsaturated Hydraulic Conductivity‘, Soil Science Society of America Journal, vol. 55, pp. 467-470.

Ankeny, M.D., Kaspar, T.C. and Horton, R. 1988, ‘Design for an Automated Tension Infiltrometer‘, Soil Science Society of America Journal, vol. 52, pp. 893-896.

Bagarello, V. and Iovino, M. 2003, ‘Field Testing Parameter Sensitivity of the Two-term Infiltration Equation using Differentiated Linearization‘, Vadose Zone Journal, vol. 2, pp. 358-367.

Bodhinayake, W., Si, B.C. and Noborio, K. 2004, ‘Determination of Hydraulic Properties in Sloping Landscapes from Tension and Double-Ring Infiltrometers‘, Vadose Zone Journal, vol. 3, pp. 964-970.

Casey, F.X.M. and Derby, N.E. 2002, ‘Improved Design for an Automated Tension Infiltrometer‘, Soil Science Society of America Journal, vol. 66, pp. 64-67.

Fuentes, J.P., Flury, M. and Bezdicek, D.F. 2004, ‘Hydraulic Properties in a Silt Loam Soil under Natural Prairie, Conventional Till, and No-Till‘, Soil Science Society of America Journal, vol. 68, pp. 1679–1688.

Logsdon, S.D. and Jaynes, D.B. 1993, ‘Methodology for Determining Hydraulic Conductivity with Tension Infiltrometers‘, Soil Science Society of America Journal, vol. 57, pp. 1426-1431.

Perroux, K.M. and White, I. 1988, ‘Designs for Disc Permeameters‘, Soil Science Society of America Journal, vol. 52, pp. 1205-1215.

Rachman, A., Anderson, S.H., Gantzer, C.J. and Thompson, A.L. 2004, ‘Influence of Stiff-Stemmed Grass Hedge Systems on Infiltration‘, Soil Science Society of America Journal, vol. 68, pp. 2000-2006.

Ramos, T.B., Gonçalves, M.C., Martins, J.C., van Genuchten, M.Th. and Pires, F.P. 2006, ‘Estimation of Soil Hydraulic Properties from Numerical Inversion of Tension Disk Infiltrometer Data‘, Vadose Zone Journal, vol. 5, pp. 684-696.

Reynolds, W.D. and Elrick, D.E. 1991, ‘Determination of Hydraulic Conductivity using a Tension Infiltrometer‘, Soil Science Society of America Journal, vol. 55, pp. 633-639.

Wang, D., Yates, S.R. and Ernst, F.F. 1998, ‘Determining Soil Hydraulic Properties using Tension Infiltrometers, Time Domain Reflectometry, and Tensiometers‘, Soil Science Society of America Journal, vol. 62, pp. 318-325.