Hawkeye UAV Aerial Farm Mapping

May 2014

Unmanned aerial craft are being used to map farmland more accurately

Hawkeye UAV Ltd has developed a small remote controlled aircraft capable of supporting two cameras, and has refined techniques for acquiring and processing data. This combination has enormous potential for use in the agricultural, horticultural, arable and conservation sectors. It can provide high quality, accurate information in a very short time frame that can inform strategic decision-making.

Hawkeye UAV Ltd began commercial operations in New Zealand in 2009. With a background in unmanned aerial vehicle (UAV) work (through military experimental research and operation), staff were well placed to develop a system that could be used for civilian commercial photogrammetry. In 2011, a new aircraft was unveiled, called the “AreoHawk”. It was named after Areo, the New Zealand based developers of photogrammetry processing software. The focus in development has been on professional grade data gathering as well as data processing and output. The staff at Hawkeye UAV Ltd consists of UAV operators, geospatial professionals, civil and military pilots, technical trades people and former Armed Forces personnel. 

Rowland Harrison is a director of the company. Like most of the staff, he is ex-Army where he was the officer running the UAV project and working on geospatial intelligence (mapping and imagery etc) to support Defence Forces’ operations. While the Army is focused on full motion video using TV type cameras in the sky, Rowland tested mapping using SLR cameras and saw a lot of potential use for geospatial and mapping applications.

“So I decided to take this forward commercially and resigned in 2009. I saw that commercial operations would provide a better platform for this technology and would be viable and exciting,” he says. “However, we started out with a defence design of UAV and it was just horrible for commercial work, so we got a government grant to design a new aeroplane that has since proved very successful. We have been working with a number of New Zealand companies to optimise our system and we are now exporting around the world and operating a significant number of teams around the country doing high resolution aerial photography and geospatial data acquisitions.”

Initially they were ahead of market demand and it has taken time for this new technology “coming out of left field” to be proven, accepted and taken up by professionals, but after five years of hard work they expect to turn a small profit next year. It has been a very hard row to hoe, says Rowland, but they now have the confidence of a number of surveyors who have bought technology and now are operating around New Zealand.

“We are now seeing that on the export side where we have had quite a lot of success, we are starting to get stretched. We have the advantage of being ahead of overseas competitors who are all where we were a number of years ago. We have learned a lot of lessons the hard way – people have the point and click expectation that new technology will be autonomous, reliable and work perfectly every time but the weather just doesn’t allow that. So you have to have a bit of a Kiwi practical approach.”

Government strategy documents indicate an expectation that the future of farming in New Zealand will be very large units and that to optimise performance it will be necessary to have aerial surveys using several million dollars worth of technology carried aloft by million dollar aircraft. However, Rowland believes that relatively inexpensive equipment can do a better job at a fraction of the cost.

“UAVs have it made in aerial photography because our GPS is worth $120 and I can probably put a $6000 camera in rather than $1 million one.   It means we can deliver survey grade data exceeding the performance of expensive technology,” he says.

“In practical terms that means we can provide you with better information about your farm than you can yourself. Instead of walking around with a GPS and taking weeks to do that, we can have it done in an hour. On the acquisition side, the data may take a day or two to process and the accuracy of on-farm mapping will go up through the roof.”

“The critical thing is that our aircraft was designed to carry two cameras, one infrared and the other RGB (red/green/blue). When we analyse the information from them we can start calculating things like biomass, protein, energy, dry matter – all really critical information for increasing production.”

Rowland explains that what the analyses provide is key information about and support for the business and is very different to aerial mapping. He points out using conventional technologies, it can take many weeks to turn around aerial mapping whereas with his technology, it could be one or two days and eventually just hours when the image processing capability is increased.

Flying over a farm, the aircraft takes a series of photographs in infra red and RGB with lots of overlap. Then come the highly computer intensive processes of ortho-rectification and photogrammetry to turn the images into accurate and useful information.

“Accuracy is important because when you fly again later and compute new data accurately, you can have high resolution indicators of real change and you are not getting errors coming in through misalignment of datasets,” says Rowland.

“We can then give farmers the answers they want such as growth in crops, energy content, feed availability and so on. And a big advantage with the UAV is that it flies below clouds so they can be active on a cloudy day, and the surveyors we have around the country are local – they just rock up and do the job, so logistically it is efficient and straightforward.”

Rowland says that the core business of the company is not aerial photography as such but the generation of high resolution 3D terrain data sets. This means, for example, that they can fly over a crop as it is sown, and do repeat flights at intervals and document accurately the growth of the crop over time by calculating its change in volume on each flight. The process will also identify areas of poor irrigation, requirements for fertilisers, herbicides or pesticides so they can be targeted and localized rather than a blanket application.

Other uses for the information include:

  • feed budgeting
  • infrastructural compliance monitoring and auditing
  • being able to prove that required changes have actually been carried out
  • valuation of properties
  • precise sizing of paddocks
  • precise locations of fences and troughs
  • adequacy of riparian margins
  • monitoring work being done
  • monitoring stock in remote areas
  • track maintenance management
  • flood and drought management and monitoring
  • monitoring weed and insect incursions
  • native forest monitoring in selective harvesting operations
  • assessing erosion after a storm
  • many other uses that will become apparent when farmers are familiar with the technology and its potential.

The biggest current user of UAV technology is the Department of Conservation, which has many parcels of land to monitor throughout the country. Some district councils are also keen to make use of its benefits.

The aircraft, a RQ-84Z AreoHawk, was designed by Sean Mitchell in Hamilton.

“We gave him a simple one page specification,” says Rowland. “We just said we need it to carry cameras on the centre of gravity, 60 minutes of flying time, the ability to fly in light rain, and we had to have parachute recovery. He went away and built an aeroplane that was rugged, stable, reliable, easy to launch and easy to land.”

It weighs about 5.5kg, has a wingspan of 2.6m and a cruise speed of 55-60 kmph. Flying time is around 90 minutes during which it can cover 5 to 10 square kilometres. It contains high precision cameras, wide-angle lenses and a ground control station based in the cockpit, which relays photographic data back to a central point.

The UAV is transportable, easy to assemble and is launched by hand. Two operators are required to launch and fly it. Similar in shape to a glider, it has been designed to provide efficient flight, high stability and plenty of volume in the fuselage to house componentry. A parachute is used for safe landings on surfaces that are often full of obstacles. Its autopilot is programmed to recover to the same pre-selected point. The system also continuously assesses wind speed and direction to calculate the optimal release point, allowing it to drift back to the operator’s required location.

Originally the UAV was designed to carry one camera with a 36.4 megapixel chrome sensor, but for New Zealand agricultural uses it now carries two 16MP SLRs.

The aircraft is critical to the business, but Rowland points out that it is only 20% of the effort that goes into the company’s services; the other 80% being the image data processing and calculating the answers that clients want.

“We don’t sell hardware, we sell full capabilities – training, aerial surveys, image processing services, image processing technology, aircraft spares etc,” he says. “We have teams using our technology in Northland, Waikato, Dunedin, New Plymouth, Napier and Palmerston North and we are looking at establishing teams in Christchurch and Nelson. They are operating under our CAA authorisation umbrella and using our central image processing capability so that we can keep the standards high.”

“We are also operating in Mexico, Mongolia, Australia, South Africa, doing the same sort of work around the world. In New Zealand the main focus of this technology is in the agricultural sector and that’s why we have redesigned our aeroplane for a twin camera set up and the results are fantastic.”