Our vision guided control systems have been designed in a modular fashion in order to service the maximum number of applications with a minimum of special hardware or software. Our systems are also designed for ease of integration into a wide range of manufactures cultivation and spraying machines.
Our world leading crop location and tracking software has been refined over more than 12 years of commercial development. That software runs on a console designed specifically for this purpose making use of a new generation of high performance low power fanless processors that can perform the necessary computation in a very compact format. The console also features a modern bright, high contrast touch screen that can display all the information the operator requires, including live video, within a single compact package. A USB socket provides a simple method of data exchange facilitating updates, backups and a means of remote support.
Control of basic implement functions such as steering are done from an implement module comprising a specially designed microcontroller board housed in a waterproof metal box. There are two versions of implement module. One is designed for relatively simple inter-row guidance systems using either disc or side shift steering. The second has the same steering functions, but has a wider range of inputs and can control implement level. Both versions communicate with the console via Gigabit Ethernet and supply power to the console via the same connector thus reducing clutter. An Ethernet switch mounted within the implement module provides a communication hub between console, implement module and GigE cameras. This hardware configuration in conjunction with flexible software facilitates control of machines with multiple cameras and multiple independently steered sections.
Our Gigabit Ethernet cameras are based on a new breed of CMOS sensors providing the best possible performance, particularly in high contrast lighting conditions. Cameras are packaged in a tough waterproof aluminium housing with a simple mounting arrangement. Our standard cameras produce colour images but for some special applications we use cameras that operate in the near infra-red. Two alternative lenses are available as standard to view the maximum number of crop rows from a convenient camera position.
For the majority of applications i.e. inter-row guidance, the equipment described above is all that is required to control an implement. However, there are applications that require additional functionality. For example, in earlier work we developed a novel rotary cultivation system that controls weeds by cultivating between individual vegetable plants within crop rows. To control these rotary blades, it is necessary to locate individual crop plants with the vision system and to synchronise blade rotation to plants as they pass through the image. For machines where these blades are driven by hydraulic motors we developed a microcontroller board that controls proportional hydraulic valves. Where blades are driven electrically we developed a different microcontroller board to drive brushless DC motors. These boards connect to the implement module via a CAN bus network allowing us to connect multiple boards of different types as required by the application.
In other applications growers may wish to spray an individual crop plant or weed with a liquid agrochemical or biological material. In the case of spot herbicide application to individual weeds this has involved the development of specialist very low volume solenoid operated nozzles. We now manufacture spot spray nozzle assemblies for these applications.
In other applications, for example, application of a nematode drench to brassicas for the control of cabbage root fly, the challenge is to get a sufficiently high volume of liquid onto the target crop plant. This has required us to develop techniques based on different higher capacity solenoid valves.
In both these cases it is necessary to turn multiple solenoid valves on and off very quickly whilst synchronised to vision tracking. To achieve that we developed a multi-channel microcontroller board for solenoid valve control that also connects to the implement module via CAN. This board can drive a range of latching and no-non latching valve types.
Where we are controlling fluids it is often helpful to monitor
pressures and temperatures. We developed a condition monitoring
board that measures analogue inputs from pressure and temperature
sensors and makes their values available to the system via the CAN
Below are examples of commercial machines from the past built by
Garford Farm Machinery that have been based on our technology: