/ 31 October 2011

Move over, Google Earth

Move Over

An unmanned ­helicopter that will enable farmers to monitor their crops, pastures and stock has been developed, and is being tested, by ­Stellenbosch ­University’s department of electrical and electronic engineering.

According to the department’s Professor Thomas Jones, the mini-helicopter will give more detailed information about, for example, vineyards and livestock than the images provided by satellites, which give broader information.

Colour bands in photographs taken by the helicopter will be able to provide information such as the water content of soil and the chlorophyll content of plants. Farmers will also be able to check on fencing and soil erosion and even count game.

Parts of the helicopter were first tested on other vehicles to make sure they were safe. The autonomous flight-control system was tested on smaller helicopters, the electronics on planes and the camera system on fixed and moving platforms.

The helicopter has a wider range than most remote-controlled craft. It can travel from 5km to 10km from its base station, staying airborne for up to 45 minutes on about two litres of fuel.

Its own flight path
Ruan de Hart, a member of the team of engineers who built the aircraft, said that, when co-ordinates of a destination are sent to the on-board computer, it determines its own flight path. Constant contact with the helicopter is maintained through a radio system linked to a computer at the base station. In this way new co-ordinates and commands can be sent to the aircraft.

The camera can be programmed to take pictures or video footage at predetermined co-ordinates or take specific pictures after real-time footage sent from the aircraft to the ground station is viewed.

Jones said farmers normally have to rent helicopters or small planes at anything between R2 000 and R8 000 an hour, excluding the photography. Renting an unmanned helicopter will cost about R1 300 an hour.

A cost-effective and dependable system should be ready by 2013, Jones said.

He is working with the Civil Avi­ation Authority on rules and regulations for unmanned aircraft. The aim is to have legislation on operating autonomous aircraft passed by 2014.

Sonika Lamprecht is a writer in Stellenbosch University’s communication and liaison department.