There are a lot of interesting options when deciding how to build an AgOpenGPS system for yourself. Do you go for a wheel motor or hydraulic valve steering, do, you use dual recievers or single, with or without bno/brick etc. to name but a few of these choices.
They all certainly seem to have potential to make an effective steering system, but I am wondering if anyone has actually tried directly testing some of these options against each other? To see just how relativerly effective some of these options are for them and what benefits or limitations the encountered.
Buying extra receivers or a lot of hydraulic components for example certainly aren’t cheap, so are they worth the investment compared to some of the alternatives?
I did not test an electric motor, as our JD 7530 came with a hydraulic valve. One thing to consider is that a hydraulic valve lets you disable autosteer by using an encoder on the steering wheel to sense when the user wants to manually steer the tractor.
I’m working on dual receiver as the heading off of a BNO055 was not good enough for me. Besides being unstable, the heading is wrong as soon as you reverse, which is frustrating.
I know you asked for some solid test cases, which I don’t have. Feel free to discard my input…
I expect direct tests to be few anyway, so certainly don’t mind any good comments.
The impression I get is that any differences are more in features an practicalities than out right line following performance. I have often seen general comments across different brands of auto steering though that hydraulic works better than wheel motors.
Reading up on control algorithms and my own limited experience, I was wondering how much is down to the logic controlling the steering rather than the general method of actuation.
I would expect hydraulic has the potential for much faster degrees per second turn rate then a reasonably sized electric motor. That being said, once on the line, both should need only small adjustments.
I have seen a couple of videos of hydraulic steering valves being tested and it was surprising just how quick the wheels could be turned the wheels from lock to lock when fully open. I have wondered how much of an advantage that is though in practice.
Again no direct test, but!
As you mention, fast turning is probably not good, especially not when close to AB line.
Maybe the difference is more to what you prefer, and if you want to use AOG on a tractor with already mounted hydraulic valves.
I went for the valve system, because that is what they have on the tractor I drive at work, and I liked very much that steering wheel does not turn when on autosteer (SBG system).
Also I remember some videos a couple of years ago (Combine forum I think) with accu drill motors for turning steering wheel and they were very noisy. To avoid noise, also lead me to hydraulic.
It seems that good electric gearmotors are not that noisy.
And today I might reconsider due to security regulations, as a not engaged gearmotor can´t move the steering wheel in any way. (There could be insurance problems in case of accident, because you have altered the steering hydraulics)