There was a time when opting for auto-boom height control meant you had little choice. Now the market is awash with ride-height control systems designed to assist the operator. Geoff Ashcroft takes a look at some of the systems on offer.
Norac is undoubtedly one of the go-to choices in the sprayer market for manufacturers looking for a bolt-on, auto-boom height control solution that could be integrated into their latest models.
But increasingly, a few firms have chosen to guide their own booms as they seek the best solution for correct spray height management.
According to Syngenta application specialist James Thomas, boom height is the single biggest controllable factor when it comes to preventing drift. With traditional booms and 50cm nozzle spacings, keeping the boom at 50cm above the target will not only ensure minimum drift, but will also ensure maximum coverage.
He says that increasing this distance by as little as 30cm, to a height of 80cm, increases drift six-fold. Which makes an effective boom height control system all the more beneficial to any spraying operation.
Chafer operates its own system called Chafer Contour, on booms up to 30m. But the development of wider booms has seen the company adopt Norac’s UC7 system, as marketing manager Joe Allen explains.
“When Norac introduced its UC7 system, it proved to be the best option for us when we chose to go wider,” he says. “How UC7 now monitors and controls the centre frame is a huge improvement over previous Norac versions. And it also suits the heavier, wider booms very well.
“With gyroscopes and accelerometers, the Norac sensor is extremely advanced, particularly in hybrid mode,” adds Mr Allen. “However, it is important to remember that any boom height control system is only an assistant – it has never been developed to replace an operator’s ability to take control and react to changing in-field scenarios.”
Sands has also elected to stick with Norac, but with UC5. The firm’s Thomas Sands says; “We have done a lot of development work with Norac and can achieve a 94% ‘on target’ success rate with UC5.
“By putting sensors just after our VG point, which is half way along each side of the boom, we can create a very effective boom height control system for positive and negative field contours.”
Knight Farm Machinery uses a Muller-based system for its boom height control. Technical manager, David Main explains; “We already run Muller electronics on our sprayers, so it made sense to stick with Muller for its boom height control system.
“Doing so was never going to be a headache getting full integration, and when you have full compatibility like this, there is less chance of operational issues that can be blamed on a third party.”
Knight ‘s package includes Distance Control 1 and Distance Control 2. The first is an entry-level solution offering raise and lower. The addition of incline rams also allows the boom to tilt. “It is a largely passive system with two ultra-sonic sensors that scan an area around 1.5m in front of the boom,” says Mr Main. “It works well across reasonable ground conditions or over a good crop canopy.”
Greater sophistication comes from Distance Control 2, which affords independent raise and lower of left or right-hand boom halves, above and below horizontal. “DC2 is a three-sensor system, but it combines two central sensors that operate as one,” he says. “We have put them outside the first boom fold point about one metre away from the tramlines, so they do not over-react from changing conditions in the tramline areas.”
Amazone also works with the Muller system, but has taken software development in-house, to make it Amazone-specific. In addition to the Distance Control options, Amazone also offers Contour Control and Swing Stop, but only on UX Super and Pantera models.
“Contour Control adds two additional sensors to the boom pendulum and includes a sophisticated hydraulic ram to manage tilt, roll and damping,” explains Simon Brown, manging director of Amazone. “It then uses four sensors on the boom for working height control.
“This system does offer fully automatic and manual modes – the latter is useful for passing a pole, and lets the operator fold one side of the boom in while maintaining full functionality of boom height control on the areas of boom still in use.”
He says the boom height control mechanism is an integrated design that operates with the sprayer’s boom suspension system. “This lets us manage boom reactions, so they can be better controlled,” he says. “Taking it a step further is Swing Stop - an electro-hydraulic control system that incorporates accelerometers on each boom tip. These link to the tilt and roll hydraulic cylinder to stiffen the boom and manage whip, managing under or over-application from excess fore and aft boom movement.”
Agco introduced its in-house developed OptiSonic boom height control at the beginning of 2020 across Fendt trailed and self-propelled sprayers.
“We are moving to common architecture across the range, to improve on-vehicle communications and integration,” explains James Wallington, Agco area sales manager. “It puts us in control rather than rely on third party integration, which also simplifies our relationship with dealers and customers.”
Where the previous system used either three or five sensors, OptiSonic uses four or six sensors, depending on boom configuration, says Mr Wallington. “The six-sensor version suits those with booms that part-fold and still operate at 24m and 36m for example, so boom height control is maintained at either spray width.”
Mr Wallington says the new system affords an active roll function to manage movement across the boom’s centre section, and offers a greater level of operator control too. “Through the 10.4 inch Vario terminal, operators can now select a wider range of boom height control settings,” he says. “Different parameters suit tramline condition, field topography and crop density. And rather than set just one function for the season, operators can now fine tune the boom reactions and responsiveness, as they move into each field.”
The challenges of negotiating irrigated root crop fields is one that puts a lot of pressure on spraying efficacy for Norfolk grower Tony Bambridge and the team at B and C Farming, Marsham. The 1,520 hectare business, which grows seed and ware potatoes, sugar beet, peas, oilseed rape, barley and grass seed, was looking to increase output and productivity through improved logistics.
“We looked at going up from 24m to 36m, which means fewer wheelings and less crop damage, though it also meant introducing tramlines in potatoes and sugar beet crops,” he says. “But before we made any concrete plans, we wanted to see how well sprayer booms would ride in one of our worst scenarios.
“We had read all the marketing materials and decided that our own on-farm trial would determine which boom could manage our worst scenario,” says Mr Bambridge. “To get the best performance from our sprays we need a sprayer boom to maintain a consistent height, close to the target to maintain its spray pattern.”
The farm’s test criteria involved achieving a 12kph spraying speed while travelling across a recently lifted potato field, at a 45 degree angle to the beds.
“It was a rough field, and was by no means exceptional, but it gave the opportunity to assess boom stability and performance,” he says. “All those we tried performed to an acceptable level, while the Horsch Leeb proved to be exceptional in terms of boom performance.”
The farm had been running a pair of 24m self-propelled sprayers and following the on-farm test placed an order for two Horsch Leeb 6LT models, offering a combined total spraying capacity of 72m and 12,000 litres.
“This change of logistics favoured trailed sprayers, as the most appropriate mix of cost and benefit,” he says. “We also had good availability of tractor power and we can run economically on low revs.”
With the 36m boom width confirmed as the way forward, B and C Farming is pushing productivity and has integrated tramlines in potatoes and sugar beet, thanks to trials work carried out by Matthew Smallwood at McCain Potatoes.
Mr Bambridge explains; “We have increased our trackwidth to 2.25m, but still grow potatoes in 1.83m beds with 36m tramlines.
“Dividing 1.83m into 36m gives 19.67 beds, so the extra 0.67 of a bed provides us with around 1.2m of space to widen the track width and create enough space to comfortably run on 580 tyres all year round.
“Matthew Smallwood proved this tramline system works, with only half the yield degradation under the tractor and sprayer, compared to non-tramline systems,” he says. “And there is zero yield loss in the first bed alongside either side of the tractor. The wider wheel track also means a more stable sprayer, which further helps to improve sprayer boom performance.”
He says the farm is now an advocate of 25cm nozzle spacing, which brings the boom closer to its target.
Sprayer operator Graham Crane says; “There is a noticeable reduction in drift and we have seen an improvement in efficacy from keeping the boom down. We are working on gently undulating ground, so the positive and negative boom movement offers only a slight benefit for us. The biggest improvement has come from the way the boom rides.”