In association with the HGCA's BePRECISE initiative
In the first of a series of three academies on precision farming, Ian Beecher-Jones, project facilitator for HGCA's BePRECISE campaign, guides growers through the basics.
More and more people are adopting precision farming systems because of a reduction in capital cost, an increase in input prices and improved compatibility between systems. However, the precision farming world can be complex and confusing if you are unsure of the fundamentals. So if you are considering the new technology on your farm, read on.
What is precision farming?
There is no global description of precision farming. It means different things to different people. Whether you say it is the use of technology to improve driving accuracy or recognising and addressing variation across a field, you will be correct. Precision farming will enhance good practice – it won’t rectify poor management.
Why precision farming?
There are many reasons why you may want to start precision farming, but with input and commodity prices changing on a daily basis, farmers are aware that maximising productivity from their fields is harder than ever. Being more accurate in making management decisions and improving your production efficiency may well lead to increased margins and profitability of the farm.
Precision farming can be split into three parts:
In this article, we will look at machine control and automation; the other two areas will be discussed in future articles.
Where do I start?
Systems to guide and steer tractors and combines have become much more accessible and are the entry point for many farmers. These can range from using a simple guidance device to navigate you up, down and round a field, to a system that does the steering for you automatically. Decisions on how to, and whether to, steer or guide your equipment are complex and should not be taken in isolation.
How do the satellites work?
The way the systems work is essentially the same – they all need a signal from a global positioning constellation of satellites in orbit. To get a position fix, at least four satellites have to be tracked by the receiver on the cab.
However, these signals will have certain errors caused by their journey though the earth’s atmosphere. To compensate for these errors, the receiver also requires a "differential" or "correction" signal. This can be supplied from a government or commercial satellite, or, for higher accuracies, a local base station can be purchased.
Precision farming techniques include satellite guidance for tractors at work.
What are the standard components in a system?
For manual guidance systems, you will require a satellite receiver and a control/display unit. For the automated steering system, you will also require an electro-hydraulic valve that fits into the vehicle’s steering circuit, an electronic control unit (ECU) to manage and control the steering system, a wheel angle sensor to provide accurate feedback to the ECU, and a wiring loom to join it all together. When using medium- to higher-accuracy systems, it is advisable to ensure the system has a gyroscope module to detect the pitch and roll of the tractor.
What accuracies are available?
The level of accuracy has a direct impact on the cost of your system, so careful consideration must be given to the level of accuracy you require, both now and in the future.
There are four levels of accuracy available:
-
Low 1 – about 1m
-
Low 2 – 20-30cm
-
Medium – 10-15cm
-
High – 2.5cm
The accuracy levels are described as a pass-to-pass accuracy over a 15-minute period. Depending on your system, you can purchase subscriptions and upgrades to improve the level of accuracy for a given period of time. Enquire whether your receiver has that option.
A common term used for the high-level system is real-time kinematic (RTK). This means a base station is positioned on-farm to distribute the correction signals from a known static site directly to any number of vehicles within range of the base station.
What accuracy, what task?
How do you recognise the levels of accuracy available, and what tasks you can undertake with them? This table provides a guide for some common tasks:
Where can it go wrong?
With an RTK base station, are you in range of the signal? Are trees, buildings and other objects interrupting the signal?
-
Is the receiver able to "see" enough satellites?
-
If your system requires a subscription, is it up to date?
-
Is it all connected correctly?
-
Is everything turned on?
This is where you will require quality support from your precision farming adviser or dealer.
Involve the operator
The skill and engagement of the tractor driver or operator are vital when?choosing a system. An operator who is fully engaged with the reasons for adopting a system will ensure it is used to its full potential.
Involve them in trialling the system and the decision-making process to choose the final system to ensure they understand how it fits into the precision farming process. If the operator recognises the benefits of a steering or guidance system, performance will increase and success is more likely.
Plan ahead
Adding technology to your tractors and machinery will work only if you have a plan for how it will benefit your business. Take advice from a range of sources, such as machinery dealers, agronomists and precision farming providers to ensure you choose a system suitable for your business. And go to an HGCA-funded Be Precise workshop.
Does it pay?
You can do some simple calculations from the start to work out costs on your farm. Have you measured your tramlines? The actual width of your cultivation and planting equipment may be different. By calculating the over- or underlap you have, you can calculate the savings you can make if this is reduced and thus the financial aspects of being more precise. The HGCA cost:benefit tool will allow you to crunch the numbers to see the benefits for your farm.