THT Header

Home About Us Technology Products Projects Videos Contact



Products

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.

  Tillett and Hague Technology Console

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.

Tillett and Hague Technology Implement module

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.

Tillett and Hague Technology camera

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.

Hydraulic rotor control boardElectric Rotor Board

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.

Spot spray nozzles

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.

Drenching nozzles

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.

Nozzle Control Board

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 network.
Condition monitoring board

Our user interface has a common style across our range of applications and is available in a range of languages including those requiring oriental and Cyrillic scripts.  The working screen for an inter-row guidance system illustrated below has the following features:
WorkingScreen3Camera
•    A live video image over which are superimposed green lines representing the template tracking crop rows.
•    Systems operating with multiple cameras display live thumbnail video from all cameras along the top of the display.
•    An image quality gauge to the left of the screen giving relative indication of likely tracking performance.  The higher the green bar the better.
•    Information symbols at the bottom left of the display (none shown in illustration).
•    A warning triangle indicating poor tracking is displayed if estimated lateral error exceeds 25mm.
•    An implement lift symbol is displayed if the lift sensor detects the implement is lifted.
•    A circular red braked symbol is displayed if the implement is down but not moving.
•    A speed gauge on the right shows forward speed.
•    A green dot and red/green chevrons below the image indicate side shift position.
•    The fine offset gauge shows the amount of left or right bias set by the user.

Touch screen buttons on the right of the working screen have the following functions:
•    Spanner symbol button accesses the setup menu.
•    Multi camera symbol button toggles between cameras affecting the main image displayed and fine offset context.
•    “Left arrow” moves fine offset left 1cm.
•    “Right arrow” moves fine offset right 1cm.
•    Touch screen button labelled “Manual” disables vision steering and allows the user to move left or right manually.
•    Pressing the touch screen button with a power switch logo enters a shutdown screen.


Below are examples of commercial machines from the past built by Garford Farm Machinery that have been based on our technology:

Robocrop vision guided hooded band sprayer
Vision guided inter-row hooded band sprayer.
Multi section Robocrop with three cameras and side shift sections
Inter-row cultivator with three sections each of which can side shift independently and each of which has its own camera.
Triple section 20 electric rotor in-row hoe working in lettuceIn-row weeder in Brasica using 3 cameras to view 9 rows
In-row cultivators
Go to top of page

Copyright © 2016 Tillett and Hague Technology Ltd