Download - Crop Spec, A Collaborative Partnership
Crop Spec, A Collaborative
Partnership A real time integrated plant nutrient monitoring and application system for
Agricultural equipment
CropSpecTM – specifications
Environment IP 67 compliant
Laser safety Class 1 or Class 1M
Physical Dimensions 200 mm x 80 mm x 80 mm
Mounting height 2 - 4 meters
Viewing angle 45°- 55°
Temperature 0 - 60°Celsius
Operational wavebands 735nm and 808 nm +/- 3nm
Supply voltage 10-32 VDC
Supply current 1 A
N status of crops can be measured by analysing reflectance spectral data => non-destructive, non-contacting
IR450 500 550 600 650 700 750 800 850
0
0,1
0,2
0,3
0,4
0,5
0,6
Wavelength, nm
Reflectance
60 kg/ha
120 kg/ha
200 kg/ha
Increase due to increased biomass
Decrease due to increased chlorophyll content
N Supply
N response trail, 1994
Impact of different N supply on the reflectance spectra of winter wheat
IR
400 500 600 700 800 900 1000
W ave le ngth 1 /nm
400
500
600
700
800
900
1000
Wa
vele
ng
th 2
/n
m
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
r2 valuesfor the correlation betweenmeasurements using respective waveband combinationsand cropcharacteristics(e.g. crop biomass, N-uptake)optimum waveband
combination
Waveband to Chlorophyll relationship
The basis for getting meaningful crop information • accurate measurements in various crops and
over a wide range of crop densities• based on know-how and extensive field trial work by Yara• 730-740 nm & 760-810 nm
Source: Reusch, 2005
Crop Spec System Diagram for X20
Implement with Liquid or Granular Application
RS232CANBUS
Topcon X20
Supports all X20 application controllers
CropSpec Parameter Calculation
Define:
R = Simple ratio of NIR reflectance (808nm) to RedEdge (735nm)
R = NIR/ RedEdge
Define:
S1 = 100 * (R – 1) Compare NDVI = (R - 1) / (R + 1)
The CropSpec parameter is defined:
S1CAL = 47 * S1 / S1REF
S1REF is the S1 measured with the reference matching filter.
The 47 factor is used for matching with YARA.