I discussed in Part 2 of the ISOBUS Task Controller (TC) series, a type of TC that uses geo-referencing for data-logging. This form of TC has an AEF Functionality called TC-GEO, but there is another type of TC-GEO that is very enticing to farmers. Using prescription mapping and TC-GEO, a farmer can do variable-rate application to control the amount of fertilizer, herbicide, or other inputs by position in the field. Some of the obvious benefits of this approach include reduced input costs, but there are also environmental benefits.
In the ISOBUS world, the different prescription areas are called Treatment Zones. TC-GEO will support a grid-based Treatment Zone and optionally can support irregular-shaped Treatment Zones as well. From conversations with those in the industry, the Treatment Zones are getting smaller – down to 1 acre or less – but extremely small Treatment Zones of <100 square feet are not common. The TC has several computing challenges with very small Treatment Zones, and the systems controlling the inputs are not necessarily quick enough to make the changes needed.
A TC can face other computing challenges. The number of controllable elements increases the computational load. Since the earth is not flat (at least according to most of us), the distance between longitude lines is not fixed and varies from 69 miles at the equator to 0 miles at the poles. For TC, an implement is described using (x, y) geometric distances from a reference point, so as an implement moves across the surface of the earth, the geo-positioned locations of the controllable elements may need to continually be calculated using the geometric offsets. In some cases approximations, simplifications, or interpolations can be used but when fields can be multiple miles long and not necessarily in a nice rectangular E-W or N-S direction, those are limited.
There is one more type of TC in common usage that will be discussed in the next blog post. That will be posted close to the time of the Spring ISOBUS Plugfest in Lincoln, NE. If you have interest in discussing any TC or other ISOBUS topics in person, that would be a great event to visit. DISTek will be there with multiple attendees. Let me know if you will be there and have any topics you wish to discuss! Click here for Part 4 of this series. Or to review Part 2, click here.
