central iowa | dpilot83 - 11/8/2017 23:27
While I'm at it I may as well explain why your method is not adequate for some situations.
AgLeaders system is measuring impact of grain on the sensor and is transferring that signal into a flow rate.
When you calibrate you're trying to tell the system how a certain flow rate creates a certain signal on the sensor.
But you are talking about mph instead of flow rates. Mph says nothing.
Let's say I have a field that has a 170 bushel yield on one end and a 25 bushel yield on the other (this actually happened to me this year due to hail).
If you want an accurate analysis of the spatial variability in the field you need a calibration load at the lowest flow rate you expect to achieve (25 bpa at 6 mph with a 12 row head is 545 bph) and at the highest flow rate you hope to achieve (170 bpa at 5.5 mph with a 12 row head is 3,400 bph) and at one or more flow rates in between those two extremes.
The wider your flow rate ranges are, the more calibration loads you should do at in between flow rates. In the above scenario you should do one in the middle at 2,000 bph. That's a big gap so another at 1200 bph and another at 2,800 bph would go a long ways towards improving accuracy.
So what if you're in the 25 bpa corn? How will you achieve a 3,400 bph calibration load? The answer is, you won't. You need to be in the good corn to get that load.
What about the 545 bph load? How will you aquire that? Well, if you're in the 25 bpa corn, you do it at 6 mph. However, if you're in the 170 bpa corn, you do it at 0.9 mph.
You also need to consider how terrain affects your flow in the low yielding stuff. Will you really go 6 mph all the time in the low yielding stuff or will you have to slow down to 2.5 mph occasionally (227 bph) due to terrain?
Doing a mph based system will be worthless in scenarios like I just described.
Sure hope we can move on to flooded impact sensors now:).
I agree with what you are saying, but NO ONE can drive consistantly (at least no one i have been around) to drive by flow rates It is too hard to do. Hence the reason i suggest to do it the way i do it. Check the manual, they will explain a scenario very close to my way. It works, does it take into account EVERY possible flow rate??? Absolutely not, but it works pretty well and there is no way to account for every flow you will encounter in a field. We have seen 200 bushel swings in the same 8 rows across the fields this year.
gave you my opinion on your original question above
Opinion as it is |