A Breakthrough in Precision Farming
Multispectral imaging with QuestUAV, Micasense and Pix4D Mapper Pro
Multispectral crop monitoring has proven to be a vital aspect of successful agricultural operations. QuestUAV’s new industrial grade compact mapper Q-100 DATAhawk, combined with the multi-spectral MicaSense RedEdge sensor, opens up new doors to maximize agricultural productivity. The QuestUAV Q-100 DATAhawk is rugged, reliable and allows easy and safe operation in open and confined environments. In combination with the five-band MicaSense RedEdge sensor, farm maps of unprecedented quality can be generated by means of the intuitive Pix4D Mapper Pro software. The following study reveals that our system provides a turnkey monitoring solution for the agricultural industry.
QuestUAV Q-100 DATAhawk
The QuestUAV Q-100 DATAhawk Ag is a compact sub 2kg mapping drone with an exceptionally easy hand-launch. The entire UAV is ultra-rugged, can be rapidly deployed and flies fully autonomous. Flight endurance is up to 1 hour at 18m/s with coverage of up to 300 hectares per flight at 400ft altitude. Multiple landing options, automatic and parachute, allow for an easy and safe operation in open and confined environments.
The agricultural edition of the Q-100 DATAhawk, the Q-100 DATAhawk Ag, carries the MicaSense RedEdge multispectral unit. This advanced, lightweight camera is optimised for use in UAVs of our type.
The MicaSense captures data in five discrete spectral bands (near-infrared, red-edge, red, green and blue with a Ground Sample Distance of 8.2cm/pixel at 400ft), enabling the creation of crop health indices and orthomosaics. High-grade optical filters deliver precise information specially targeted to agricultural applications.
Image Processing (Pix4D Mapper Pro or MicaSense ATLAS)
There are several options to process MicaSense data and to generate orthomosaics and crop health indices. We found the following two options as the most practical solutions for farmers:
- MicaSense ATLAS offers a powerful cloud-based data service for storage, processing, analysis, and presentation of multispectral data.
- Pix4D Mapper Pro allows to convert multispectral images into accurate index maps and orthomosaics via intuitive software control.
Project Objectives and Scope
Our study took place at a representative precision farm in the Northeast of England in February 2016. The farm has a total size of 172 hectares and was planted with winter wheat, one of the most common crops of the region. The whole farm was covered by a single 32 minute Q-100 DATAhawk flight at 400 ft altitude. During the flight, 945 multispectral MicaSense RedEdge images were taken and processed in Pix4D Mapper Pro and with MicaSense ATLAS.
The key objectives of our study are:
- to prove the ease of use and reliability of the QuestUAV Q-100 DATAhawk
- to assess the quality of the MicaSense images
- to find the best way for a farmer to process and make use of the imagery.
Our study focuses on the technical parameters of the system and excludes farm-related analyses, such as an assessment of plant stresses, characterization vegetative cover or yield estimations. A separate report will cover the farm analysis with the progressing growing season in 2016.
Results and Conclusions
QuestUAV Q-100 DATAhawk – Safe and Reliable
Even in high winds (up to 25mph), the Q-100 DATAhawk flew a stable autonomous route and still achieved a comparable data quality to the QuestUAV Q-200.
Only 10 minutes of preparation were required from arriving at the site and getting airborne. Hand-launch, auto-pilot and parachute landing guaranteed a safe and reliable operation at any stage of the flight.
MicaSense RedEdge – Multispectral Imagery for Farm Index Maps
Every second, MicaSense captures data in five discrete spectral bands. At 400ft flight altitude, a spatial resolution of 8cm is achieved. Fully processed MicaSense products are reflectance-calibrated image mosaics of single bands or combinations of bands. Each layer of the reflectance-calibrated file (GeoTiff) is normalized so that a pixel intensity of 32768 corresponds to 100% reflectance for each band. All GeoTiff-Layers are registered to other layers at the pixel level. Through spectral calibration, images taken at different dates and light conditions become comparable.
Image Processing- Pix4D Mapper Pro and MicaSense ATLAS
The images were processed with Pix4D Mapper Pro and through the MicaSense ATLAS service. Both processing options provided comparable results in terms of image quality and variety of image products (orthomosaic, NDVI, NDRE, digital elevation model). However, the concept of Pix4D and ATLAS to produce farm-relevant image products is different.
MicaSense ATLAS offers a cloud-based processing service. Source images are uploaded to the cloud and are processed by MicaSense. The output is visible on a website (password-protected) or can be downloaded as GeoTiffs. The service requires no knowledge on image processing and is charged per hectare.
QuestUAV’s new compact mapper Q-100 DATAhawk, with the MicaSense RedEdge sensor on board, is a reliable platform to capture high-quality multi-spectral data for agricultural applications. The Q-100 DATAhawk allows an easy and safe operation in high winds and confined environments. Different processing options, like the professional photogrammetry software Pix4D, allow to easily process the MicaSense data and to create reflectance-calibrated image products. Overall, the tripartite system, Q-100 DATAhawk – MicaSense – Pix4D, has proven to be a reliable turnkey solution for agricultural monitoring.