MultiWii

to be honest I've kinda given up on Baro on my Crius AIOP v2 board ... I got down to -12m (and still descending) the other night while my quad was sat on the floor for about 20 mins for some testing of the latest pre release version. Same for me, I never got good results on altitude with my AIOP V2...

Hi,
One question: do you plan to integrate changing pids with POT value and Ziegler-Nichols algorythm as described here:
viewtopic.php?f=7&t=1701
?
Thanks

yes, you're right, the compiler do not cast implicitely intermediate result:
http://www.avrfreaks.net/index.php?name ... 61&start=0

Hi, I found that constant GYRO_SCALE in the code is computed at each loop. It looks weird to rely on the computer to dothis optimisation. What do you think ? in IMU.ino #define GYRO_SCALE ((2279 * PI)/((32767.0f / 4.0f ) * 180.0f * 1000000.0f)) //(ITG3200 and MPU6050) ... void getEstimatedAttitude()...

New fights test today Well, I am not yet convinced by alti, but it starts working a bit. I now understand better the problems: the baro pressure is not accurate enough and need to be averaged. ok I have done a runing average on 32 values. As the estimated altitude function is supposed to be running ...

I tried to integrate Mahovic code in my 2.2, but it does not give better result. So, I'll stick with my own code changes and the running average. It seems to give the best results (on the graph at least) from all I tried. Once I have understood and implement how the altitude pid works, I'll try agai...

You could also think of having a second baro on the kopter and take an average of both. My guess is that the baro should not drift that much if it is sufficiently compensated.

I understand that conf.P8/I8/D8 values are correct, but the way they are displayed is not. There should be a reason, but i don't know it. May be someone can explain ?

I use version 2.2, and I understood that code from mahovik was integrated in that version. I flew again today, stability with gyro and pid set with Ziegler-Nichols is sooo good. Stable mode could be better not as good as naza. Alti still does not workwell , I get big variation between +-3 meters eve...

while this code takes care of the wait time for the temperature/pressure conversion inside the barometer (see documentation of the MS5611 and different timing for the BMP baro). Agree, but 40Hz is not that much, especially with a running average based on 32 values. Anyway, it should'nt solve my bad...

Hi, When I move up or down the quadro, I see baro(Alt) changing on the graph almost immediately. So i assumes that the running average on 32 values does not really induce significant lag. Yesterday I did flight test with my code changes. Very disapointing. The altiltude hold does not work better, ev...

The last graphs on baroPressure value show that the value is still not regular enough. So I try to make a running average on that value and see the result. i use a table with 32 entries, which is quite a lot of computations still, but gives better results: in IMU.ino #if defined MS561101BA #define B...

Bonjour Alexinparis
In the MS5611 datasheet, ms561101ba_ctx.c[] is an unsigned int 16. So shifting left should not a be problem and values subtracted should still be within int32 range.

I found it here:
http://en.wikipedia.org/wiki/Ziegler%E2 ... ols_method

Scales are the sames, if you compare those 2: with alt: http://www.multiwii.com/forum/download/file.php?mode=view&id=2119 with baroPressure instead of alt http://www.multiwii.com/forum/download/file.php?id=2124 Thanks for the hint about baroTabSize. I'll try also with my own mean average calcula...

So let's continue the story.. I checked the baroPressure value just after the temperature and pressure compensation as recommended by MS5611 datasheet. To view that value, I changed the "Altitude" by "baroPressure" value in datas sent by kopter to the PC. The result is this, the ...

Could these calculations also be done in the GUI, freq and ku instead of PID values? Are the GUI values = program config. values? I suspect not, the formulas with the osc. frequency of 2Hz, P and I should have the same value, this is not the case in the GUI (P=3.3 I=0.045 for example)! Very confusi...

Does it really make a difference if you do the lengthy calculation after the temperature readout instead of the pressure readout? I don't expect real diference. A good baro is a baro with a lot of lag so it averages over a long time and then the pressure is pretty stable. But since this one needs t...

I 'd like to start a new thread related to ALT hold and MS5611. Yes, another thread on same topic you could say, but the idea is to use it also as a reminder for myself After several tests, and several trial of PID tuning, I was unhappy with the altitude hold. My quadro flies pretty well on gyro and...

By default PPM signal out on the 8FG is 8 channels. 12Ch out can be configured in the trainer menu, but I am not sure it works; at least it does not between two 8FG. Also, the multiconf does not show chanels above 8, but if you affect pot like I did, you should see related config values changing in ...

SBUS does not work for me. Most channels are working fine, but I can see on multiwii.conf a lot of jitter on some channels.
Has anyone experience same problem ?

I made a new version with 4 more pots in order to use 12 channels total. RC must be PPM (SBUS does not work for me) to get 12 channels. Now, I can tune almost all in flight (gyro R+P), level, alti, pos, posR, navrR (oy yaw). Your RC should have enough pots of course to do this. In multiwii.ino, at t...

to 4eprops: yes <first post edited>

just replace all "div_int" by "/"

ah, yes i forgot this: at the end of the annexCode() function

(post edited)Hi, I just tried the PID tuning together with the Ziegler-Nichols method on my quadri. I am pretty impressed, so far it works great. Before I was trying to tune by hand but never get good results. One pot (aux3) is for for gyro roll and pitch (same values for both), and one pot for leve...