Mobile low-cost 3D camera maize crop height measurements under field conditions
To tackle global challenges such as food supply and renewable energy provision, the improvement of efficiency and productivity in agriculture is of high importance. Site-specific information about crop height plays an important role in reaching these goals. Crop height can be derived with a variety of approaches including the analysis of three-dimensional (3D) geodata. Crop height values derived from 3D geodata of maize (1.88 and 2.35 m average height) captured with a low-cost 3D camera were examined. Data were collected with a unique measurement setup including the mobile mounting of the 3D camera, and data acquisition under field conditions including wind and sunlight. Furthermore, the data were located in a global co-ordinate system with a straightforward approach, which can strongly reduce computational efforts and which can subsequently support near real-time data processing in the field. Based upon a comparison between crop height values derived from 3D geodata captured with the low-cost approach, and high-end terrestrial laser scanning reference data, minimum RMS and standard deviation values of 0.13 m (6.91% of average crop height), and maximum R2 values of 0.79 were achieved. It can be concluded that the crop height measurements derived from data captured with the introduced setup can provide valuable input for tasks such as biomass estimation. Overall, the setup is considered to be a valuable extension for agricultural machines which will provide complementary crop height measurements for various agricultural applications.
KeywordsMaize crop height Mobile field measurements Low-cost 3D camera Terrestrial laser scanning
We want to thank Sabrina Marx and Katharina Anders for their support in the field campaigns. Furthermore, many thanks to Markus Wolf and Steffen Linnenbach for granting access to the maize field.
This study was performed within the research project ‘4D Near Real-Time Environmental Monitoring (4DEMON)’ funded by the Federal Ministry of Science, Research and Arts (MWK), Baden-Wuerttemberg, Germany.
MH and BH designed the experiments. Experiments were performed by MH. MH drafted the manuscript with help and contributions from BH. Analyses, figures and tables were mainly performed and produced by MH. Both authors read and approved the final manuscript.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
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