With an eye on expanding the role drones have on farms, Tristan Steventon has recently obtained a new kind of drone operator licence called BVLOS – Beyond Visual Line of Sight.

This new Civil Aviation Safety Authority (CASA) accreditation will allow him to place autonomous drone docking stations within farming locations. They will be supervised remotely, without the need for a pilot to attend the site.

Mr Steventon is the founder and director of StevTech, a company that focuses on imaging technology and works in conjunction with commercial spray drone operators such as Aussie Drones’ Aaron Parker. At the recent GRDC webinar on aerial spray application, Mr Steventon spoke about on-farm automated drone docking stations.

“The idea is to have a weather station and a drone at the side of a paddock collecting ultra-high-resolution data routinely that feeds into a decision-making matrix and also produces files for a spray rig or for other actions,” Mr Steventon said.

This new technology is being evaluated in a GRDC project in central-west NSW. The trial involves two adjacent 100-hectare paddocks. One is being managed traditionally by an agronomist. The other incorporates the use of automated computer vision technology, including drones, satellite imagery and artificial intelligence (AI).

This is precisely the kind of testing Mr Steventon encourages to help mature agricultural applications of drone technology and his company is enthusiastically participating.

Uses and licensing

With the on-farm use of drones expanding, Mr Steventon, who was introduced to drones and imaging technology while serving in the military, also provided a timely overview of uses and licensing requirements. He divided on-farm uses into two categories: spray application and image gathering to derive weeds maps and other insights about a crop or the environment.

There are different licensing requirements for different-sized drones:

• less than two kilograms non-commercial  – no restrictions;
• less than 2kg commercial – requires drone registration and operator accreditation through the CASA website, which takes  the form of a quiz;
• between two and 25kg over your own land – requires drone registration and operator accreditation through the CASA website;
• more than 2kg commercial operation – requires a Remote Pilot’s Licence (RePL) and a Remote Operator Certificate (ReOC); and
• between 25 and 150kg (spray drones) over your own land – requires a RePL and operational record-keeping, and the operator may not receive payment for services rendered.

The RePL licence involves a six-day course and includes an exam and a flight test. Figure 1 has more information about spray drone characteristics.

Mr Steventon said his experience of working with spray drone subcontractors had been overwhelmingly positive, especially regarding the efficacy of getting product into the crop.

However, he noted that the industry was young and lacked the decades-long experience of aerial applicators.

He encouraged drone operators to “put their shoulders to the wheel” and acquire a better understanding of spray dynamics from drones. He also noted a role for chemical companies to derive recommendations specifically for spray drone applications, including an understanding of micro-drift for various products.

“I’m saying that to encourage growers  and agronomists – including through the GRDC National Grower Network – to put together ideas around how to obtain a better understanding of how to more fully benefit from drone technology,” he said.

He provided an example of a grower  in Griffith, NSW, who included tomato plants within the sprayed paddock as a way to measure drift. The drift was estimated at less than five metres for that drone operation.

Mr Steventon also discussed how imaging drones and computer vision (AI-based image processing) were used at StevTech.

The technology covered both green-on-brown (GoB) weed detection and green-on-green (GoG) weed mapping. Examples provided of GoG included detecting radish in canola, ryegrass in wheat and nightshade in pasture.

However, applications for computer vision are expanding.

Figure 1: StevTech spray drone characteristics.

Source: StevTech

Growers take to the skies

The operation of aircraft, spray drones and a new option – on-farm automated drone docking stations – were covered in a recent GRDC webinar.

A better understanding of aerial applications has been raised at several National Grower Network meetings.

More information: to view the webinar, go to GRDC past online events.

Read also: Getting the most from aerial spraying and Wet years a potential challenge for global market requirements.

A range of support materials on aerial application are available to agronomists and clients from the Aerial Agricultural Association of Australia (AAAA) website, including the ‘Agronomists’ Guide to Aerial Application’ which can be downloaded for free as an E-Book.