Seeing the lie of the land from above

SHARE

Philip Brown sets up his drone's flight path with a tablet computer

Philip Brown sets up his drone’s flight path with a tablet computer

By John Keast

Rakaia contractor Philip Brown has the world, as seen from above, at his feet.

Mr Brown, who usually specialises in heavy machinery, now has a lightweight tool – a .75kg drone – that can do aerial mapping with great accuracy.

The Swiss-made drone can fly for 40 minutes in an area defined by the operator – Mr Brown, holding a special tablet computer – and takes hundreds of images and, when downloaded, stitches them together into one high-resolution image.

A field or farm boundary can be mapped to within 25mm accuracy, and the series of photos, if wanted, can show contours and heights.

It is all possible through global positioning systems and triangulation.

In the field, Mr Brown opens Google earth and then defines the area to be mapped.

That information is relayed to the drone, which can cruise at between 40 and 90 kmh.

It is launched by hand – thrown up – and then orients itself and sets off on the course, taking photos as it goes.

On the ground, Mr Brown is able to see the drone’s speed, its orientation, its rolls or turns, and, if, say, conditions change, it can be brought back to base immediately.

Left to itself, the drone maps the area set for it, assesses wind direction, and then returns to where it was launched by flying back into the wind.

Back on the ground, the data is downloaded into a computer file.

Mr Brown said a technician came from Australia to teach him how to user the drone and associated software and he is already doing intricate survey work, including the Rakaia River.

“You can fly one area and get so much data. It takes a series of photos and stitches them together. It’s ideal for farm mapping.”

The drone is so advanced it shuts off its propeller momentarily to avoid vibration when a photograph is being taken.