Weed spraying system – Hardi, GeoSelect

[Lucy] Hi, I'm Lucy Reed, AgTech Extension Officer at South Australian Department of Primary Industries and Regions. We're here at a property in Port Arthur in the northern York Peninsula and we're here to see the Rubicon 9000 sprayer for Hardi with the GeoSelect technology. Currently we're here with Andrew Snowball and Heath Thompson from Hardi. So, for all the farmers and that out there that love things like horsepower, how many horses are we talking under that hood?

[Andrew] So the Rubicon's got 375 horsepower. It's got a road speed of up to 50 km/h. It's a self-propelled unit, so combined all-in-one tank, boom, the whole lot. There are options on boom sizes from 36 metres to 54 metres, which I believe is the largest, with different nozzle technologies that go on to that. So this is assembled in Adelaide, South Australia, and the GeoSelect part is obviously designed and made also in Adelaide, South Australia but for Australian conditions. So the only additional parts over and above a normal sprayer are the four GPS units. So you've got two in the centre, and then one on either boom that measures the angle of the boom as opposed to just assuming it's a rigid structure. And then this one here has got 49 individual sections of a metre wide, that, it's got air lines and a 12 volt electric system, so, and the associated wiring and stuff for that but that is the only additional parts. There's no extra can systems, no extra cameras, no extra power systems. I guess one of the things we wanted to do, again, is not put so much hardware on the boom.

[Lucy] So it's easier for maintenance and fixing?

[Andrew] I guess it comes back to that design where we want the farmer to be able to fix the machine, if there is a problem, fix the machine themselves or have the best chance to do that hopefully, with your box of tools and stuff like that, you can make a few adjustments and get going again. Each section of a meter wide is actuated pneumatically or by air which is done through a solenoid, which is a 12-volt solenoid.

[Lucy] And can I just ask why the four GPS receivers? Is four a good number, or do you need more, or less?

[Andrew] So there's two in the middle, uh, centre section to get a very accurate heading and then two either side to know where the boom wings are, so yeah. So that you actually see in the in the user interface as we swing around, which we will, that you actually see the boom swing around. The boom is not actually one rigid part. It actually flexes and in bigger booms it flexes even more. So, you know, if I was to push that back there, actually is it at the end, there it's a couple of meters so that can actually be the difference between hitting and missing a selective spraying operation. Some camera sprayers, yeah, whatever is in front of it, if you wave a bit of, you know, grass in front of it, it will spray. This knows where it has and hasn't sprayed so if you are turning and one of the booms moves backwards over that area, it won't spray that area.

[Lucy] So Andrew, just talk us through GeoSelect: What's the process from start to finish with this?

[Andrew] In summer, the first thing that the farmer would do is get a drone operator to come out and fly the paddock. So that would capture an image of the paddock. That's all then processed and put into a dyna map which is basically a weed map of your paddock. So everything is there prior to actually moving the sprayer into the paddock. So all the decisions about how much to use, whether you want to actually spray the paddock, how fast you want to go, which way you want to run your a-b lines, can already be determined before you get in the paddock. Once that you've got that data, it's either transferred by the cloud or a usb stick or something, something similar, into the sprayer, and then it's as easy as just rolling up, turning it on, and driving around.

[Heath] Andrew's about to start the Rubicon up.

[Andrew] Okay, so I'll start the machine, fold it up, and then you… I'll then give you a yell, and then I'll unfold it.

[Heath] The sensor that we have can pick weeds up down to about a five cent piece and what we realised, that, when we started using this high resolution data, that, um, having a single GPS antenna on the roof of the sprayer was not sufficient, accuracy-wise, to work with the high resolution data that we had. So you'll see on the boom as it passes through that you've got four GPS antennas on the boom and that what that's doing is measuring where the nozzles are down to a centimetre and allowing the scan data to be most effective in the sprayer. It's particularly useful to have selective spraying on, on large booms, because the amount of air you can cover. You save on fuel costs and amount of hours on the paddock, over a 36 for example, and you're able to get a lot more done in a lot shorter period of time.

[Andrew] Okay so at the moment, we're going to spray this paddock with 100 litres a hectare and the GeoSelect will work out where that 100 litres of heat has got to go and where it doesn't have to go. So there's various views on the Rubicon. But we'll get going there. So we'll get rolling. Okay. So just turn a wet spraying. And get our boom point going. My map in there. As you can see that the boom switch on and off as well as the, ah… as well as the boom yaw. So you'll see the booms move on the screen as well as out in the paddock. So at the moment we're doing only 10 km/h but we'll speed it up from there.

[Heath] So we're using NORAK auto height on the boom. It's important with a large boom like that to have some auto leveling capability. The NORAK system uses ultrasonic and we've used it and worked quite closely with Topcon to implement the system on our large booms. The nozzles are going off using the drone data. I don't know if you can see in the camera, but we've got LED lights to turn on when the nozzles activate and we do that in the evening when the light starts to come down a bit. It makes it a lot easier to see what's spraying and what's not. On this particular Rubicon we're running two nozzles per section at a 500 mm spacing, so you've got one metre per section going off at any one time. Because the nozzles are not even fan, the software is configured in such a way that you're never half-spraying a weed. It's allowing for the uneven nature of a traditional nozzle. On this system, we're running two separate spray algorithms. You've got a h-select system which is able to blanket spray at a varying rate and you've got a selective spray system which is a single nozzle out of the four nozzle system.

[Andrew] The system knows where it is by the GPS units on the boom. So when you feed a map into it, it is basically as you move around the paddock, it knows there's a weed coming up, so, say, 500 metres down there, there's one single weed, it knows that there is a weed coming up and whatever part of the boom passes over that weed, it will command the unit to spray that particular section at that point, whether you're turning, whether you're reversing, whether you're going 25 km/h or 3 km/h, it doesn't matter. When you pass over that weed, it knows it's there and it will turn on the appropriate section. The other thing it lets you do, is in heavier areas, it can recommend that there's a heavy area coming up for weeds, to slow down and you'll save money as opposed, you know, you can have a real like light section or even nothing for a long time, and it can just say no, do 35 until you get to the next area because you're not actually going to spray.

[Lucy] Would you say that this was a good system for time efficiency?

[Andrew] So it's a little bit of a change in the workflow. I guess it's not just jump in the sprayer and, you know, out you go. But I guess, most of the times that we've talked to people that in summer, spring, they, farmers, know they're going to be spraying well before they actually are going to be spraying. In that time, that you would have the drone operator come out and scan and then if you're scanning today, say the paddock today scanning today, then it'd be spraying tomorrow.

[Lucy] So with being able to image exactly where your weeds are, so you are spot spraying. What would you say the cost efficiency would be or savings?

[Andrew] So if you've got all the weeds pushed up into the corner it'd only be one or two percent of the area that you'd actually need to spray. Obviously you're going to spray more than that one or two percent because you're going to have overlaps here and there. I mean, what we say is up to 90 but it depends on what your paddock is like and how many actual weeds you have in there, and also how fast you run. The faster you run over that map, the more you'll spray. The nozzles can only turn on and off within a certain amount of time so if there isn't enough time for the nozzle to turn off before the next weed comes up, it will just stay on.

[Lucy] So you're definitely getting more paddocks per tank?

[Andrew] Yeah. Less time having to go back to the farm, fill up you know, put more chemical in and that. Plus strategic decision-making is that you actually know what's out there before you get there, so you can plan logistically for chemical deliveries or whatever else is going on, rather than, you know, at the moment I'm just buying how many hectares I've got. At the moment, it's only fallow weeds that we're picking up, but into the future, potentially, if you can detect it with you know, a drone or a sensor or something like that, then if you can detect fungal and you can map it, you'll be able to do it. I guess that leads on to the old green-on-green question. You know. Same deal. When the sensors and that are able to pick up reliably a green-on-green so you've got, I don't know, rye grass in a wheat paddock or something else in lentils, you know, turnips or whatever you got, if that's able to be mapped, then this is able to be done. So there's no change in hardware on the machine for doing other applications as long as it can be detected by the imagery done at the start.

[Lucy] For this rig, who would your ideal customer or target market be?

[Andrew] For the Rubicon, because of the size and the boom width it'd be your large broad acre farmers, contractors, that sort of thing.

[Lucy] Thank you Hardi for inviting us out to see the Rubicon 9000. Thank you to Paul Jarrett for letting us see your property and utilise it for today. If you'd like to find out more about ag-based technology in South Australia please head to the Department of Primary Industries and Regions website.