I don’t think anyone is using robotic vacuum mode. In practice, it’s much easier to get the game rotation vector information on demand using the sparkfun library (which can be transformed into the exact same thing as RVC mode outputs), rather than continuously parse the RVC stream.
Hello
Which version of the Witmotion did you use ? There is a lot of version available in store.
This is the raw gyroscope data. Gyroscope give a angular velocity in rad/s. So you have to make an integral of this value to obtain an angular position. And you don’t have the benefic of filtering the gyroscope value by the accelerometer data throught kalman filter (which makes the BNO085 in game rotation vector mode).
Here is a good document (in french) who explain the advantage/drawback of each sensor used alone and the benefic to combine them : http://starlino.com/wp-content/uploads/data/imu_guide/GUIDE_D_UTILISATION_D_UN_MODULE_DE_STABILISATION_INTEGRE.pdf
Math
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Hwt901b ttl version
Hope its the right thread for my question: I use the cmps with v5.2.1. It seems like on rough ground, roll correction is not fast enough to keep the tractor driving straight. It tilts when driving over a little hole and starts to correct the wheel angle, leading to a curve in the otherwise straight ab line. I tried to set roll correction to different values, from 2 over 20, 50, to 80 and higher, but I can see no difference. How can I get AOG to correct for roll properly?
Which setting do you have in mind?
You can reduce your roll filtering to zero should help.
But what does roll filtering do in the end?
My guess is that it averages the readings and eliminates small jitters but the side effect is that it slows down the roll readings.
I tried to get a reaction while standing still and moving the sensor by hand. With antenna type fix I get no reaction at all (distance to line stays the same). If I set antenna type to vtg I get a reaction, distance changes as expected. Does that make sense? What does vtg mean after all?
I found same behavior (with bno085 on pcbv2) jand also v5. 2.1. I experimented with filtering and the antenna height. Decided in the end to set height to 0 m, even though it in real is at 3m.
Does that really help? I mean with 0m antenna height you cant get any correction at all? Maybe I should install 5.2.2 and see what happens…
Correct no correction, but I see it this way: when tractor is on a slope (up to the right ) antenna is a little to the left, forsing tractor up hill and that way compensating for down sliding. If you want more hill compensation you can add some degree per roll in the hill comp sektion.
The wiggle of antenna on uneven ground can be evened out with more heading compensation (I use around 60 imu 40 gps)
VTG mean reading the heading in the message from the GPS string instead calculated in AOG
When you tested in Fix to Fix do you moved a bit to set the direction? AOG cannot have a heading before it moved a bit.
By the way I have experienced the same all year long with all ver 5 up to 5.2.2. Real bad roll reading on rough ground making the tractor wobble after a bump. In FIX to FIX mode, CMPS14, tried more or less roll filtering, I saw no big effects.
With 5.2.2 i can see the behavior I’d expect. simulate a tilt of ~1 deg leads to 3-5 cm of distance to the ab line. Cant test it in the field now, but after the rain I will drive a bit to see if it works…
Seems to me that:
with CMPS you get lucky if it works properly;
BNO you buy something not so cheap that works like cheap MMA 8452;
Resume: why don’t make IMU for v5. with MMA 8452?
Having a slight problem probably something daft. I have set up a separate IMU using a cmps 14 and nano. The roll seems to work fine but the heading seems off. When I drive forward the tractor on the screen crabs at an angle to the direction of travel. I have the cmps mounted with the pins facing forward. Has anyone had this problem?
Hi @Vili your Cmps ;ino is not available for download. Could you please upload it again. I want to try it with my V4.3.10 version. Thx !
If you want use CMPS14, you need upgrade to V5, CMPS14 don’t work in V4. And ino file is in support folder of V5
I though the use of CMP0S14 was possible with V4. My BN0 went bad, and I bought a cmps compass. I plan to switch toV5 after the harvest… Thanks for the answer
You can send it to : palma__@__lavache.com (remove the 2 __). Does it work as you want ? Thanks a lot !