This is the new Amazone AmaSpot weed-detecting sprayer

A 24m (78ft) version of the Amazone UX trailed sprayer is the first to be offered with the AmaSpot weed-detecting and spraying system.

Designed for herbicide applications to stubbles post-harvest or to combat weeds before a new crop emerges, the new technique employs chlorophyll-detecting fluorescence sensors positioned 100cm (39in) apart on the sprayer boom and ‘looking’ 60cm (24in) ahead.

Chlorophyll-detecting sensors (1) detect the presence of a weed or weed patches against a bare background, triggering the nozzle control system (2/3) to spray herbicide in the right location.

Each sensor scans the ground in 4 sectors, each 25cm (10in) wide for accuracy, while quick-reaction pulse width modulation control of the nozzles switches the spray on and off in the fraction of a second.

Amazone UX AmaSpot

Amazone and its technology partners Rometron, which developed the technology from a research project at Wageningen University, and nozzles manufacturer Agrotop, say AmaSpot works with centimetre precision at speeds up to 20kph (12mph) day or night.

Using pulse width modulation with a high frequency of 50Hz means also that the spray rate can be varied infinitely between 100% and 30% without affecting the droplet size spectrum.

Sensors placed 100cm (39in) apart scan a 25cm (10in) strip each.

Amazone envisage the AmaSpot system being used for selectively spraying individual weeds or volunteers from the preceding crop, or applying a blanket spray at a reduced rate while introducing an increased rate of herbicide wherever there are high populations of the target weeds.

Both methods would reduce the total quantity of herbicide applied and increase sprayer work rate because the tank would not have to be replenished so often.

The Amazone UX AmaSpot is the first commercial sprayer to use the system; it is available in sizes of 4200-litre and 5200-litre (1100 and 1370 gal) with a 24m (78ft) boom.