Re: [Paparazzi-devel] Multirotor Flights

[Kadir ÇİMENCİ]

Hi Loic,Sergey

Thanks for the answers. I implement all of the advices you give.

Ins type =hff
Horizontal ref. gen. omega = 36deg/s
GUIDANCE_H_APPROX_FORCE_BY_THRUST = TRUE
GUIDANCE_H_THRUST_CMD_FILTER = 40
GUIDANCE_V_HOVER_KP and GUIDANCE_V_HOVER_KD are increased.
GUIDANCE_V_ADAPT_NOISE_FACTOR  = 0.8

Today the weather is rainy a lot here. I will test the new changes next week. By the way i start to study the hff filter in the paparazzi project. I have some questions on my mind .

1) Do you advice me to use GPS_LAG . I am using ublox lea6s right now. And i have a gps lag of 1 sec , approximately.

2) Do you use HFF_UPDATE_SPEED  option , or only using the hff for position estimates ?

3) I notice the horizontal filter uses ''imu.accel'' values for the input of measurements . Can we trust on this approach? Because besides the translational accelerations, the orientation changes on the frame (roll/pitch) will create accels on x and y axis. Doesn't it create error at the output of the filter?

Thanks ,

Kadir

2014-02-27 22:26 GMT+02:00 Sergey Krukowski <address@hidden>:

Hi Kadir!

I'm using the GUIDANCE_H_APPROX_FORCE_BY_THRUST = 1, the idea of it is correcting the horizontal commands depending on thrust command. And it works, horizontal acceleration from hovering and horizontal speed become smoother. I would recommend at least to try it. In worst case you will just see no difference at all. Also change the default GUIDANCE_H_THRUST_CMD_FILTER to a value in range of 30 - 50.
I would also recommend to use HFF as well.
Regarding vertical stability - try to increase GUIDANCE_V_HOVER_KP and GUIDANCE_V_HOVER_KD values (higher PID controller values), also helps decreasing GUIDANCE_V_ADAPT_NOISE_FACTOR value to about 0.7 - 0.8 (let the adaptive filter to adopt faster to changing hover level thrust, which is especially the case in windy conditions).

Best Regards,
Sergey

Hi Loic,

I see 3-4 meters of oscillations , yes i protect the whole imu with a foam
, in laboratory i see the altitude value from the ins seems correct with
error less than 30 -40 cm. Yesterday the altitude hold was great, and the
copter was climbing/decreasing regularly and stopping at the desired
altitude regulary, i will test it again tomorrow. By the way do you have
any idea about using horizontal ins 'HFF' and '
GUIDANCE_H_APPROX_FORCE_BY_THRUST' ? They are closed in my project right
now, i m not sure about using them ..

Thanks

Kadir


2014-02-27 20:05 GMT+02:00 Loic Drumettaz <address@hidden>:

Hi Kadir,

What amplitude are the altitude oscillations with wind? They should be
less than 2 meters.
Did you protect the barometer with (permeable) foam?
Good luck with your next flights.
Loic
Le 27 févr. 2014 14:26, "Kadir ÇİMENCİ" <address@hidden> a écrit :

Hello everyone,

Yesterday i have  successfull flights with vertical hover and  rc climb
modes in vertical modes. This morning the weather was windy a lot and i see
great oscillations in vertical around the setpoint with the same vertical
p,i,d parameters, i guess it can be caused by the pressure changes with
strong wind, is this idea true ?

Secondly, i have flights with horizontal hover today they were really
successful. My quad accomplished to stay at a point with errors of +/-1
meters approximately, against a little wind. Tomorrow i am planning to fly
with navigation mode but i want to ask two questions.
1) Is it recommended to use 'GUIDANCE_H_APPROX_FORCE_BY_THRUST ' ? The
idea behind of this seems very successful to me..
2) Is it recommended to use 'HFF' horizontal ins ? Is  there anyone who
have flights with this filter? Right now i am using only 'VFF'  at INS
subsystem.

Frame : Quad - Cross
Board : Lisa/m v2.0
Software : master

Parameters i use ;
Vertical P = 300
Vertical D = 30
Vertical I  = 20

Horizontal P = 50
Horizontal D = 50
Horizontal I  = 20
Horizantal A = 10
Ref_max_speed = 3 m/s
Ref_max_accel  = 2m/s^2
Max bank = 45 degree




2014-02-14 19:18 GMT+02:00 Loic Drumettaz <address@hidden>:

Hi Kadir,

The next step for you is then to be able to switch to hover mode. For
this you need to calibrate the magnetometer and define the local magnetic
field in your conf.
Also, before the first hover you should check that the magnetometer
measurements are not corrupted with motors current magnetic field.
Actually these current are mainly generated by power wires, which must be
twisted to reduce the magnetic field generated. Also, the magnetometers can
be calibrated to compensate this. See mag current calibration on the wiki.

After the first successful hover, it should be quite easy to switch to
nav using example airframe configs and flight plans.

For the nav, first you can take off in rc mode, and tune the horizontal
guidance loops and reference generator by moving from a waypoint to another.
Then, the vertical nav (loops and reference generator) can be tuned by
moving the waypoint altitude.
This is well documented on the wiki, maybe a step by step tuning page
could be added...
After this, you should be able to perform autonomous take-off and
landings.
Once there, do not hesitate to ask for more tips.
Loic
 Le 14 févr. 2014 07:29, "Kadir ÇİMENCİ" <address@hidden> a
écrit :

Hi Loic,

At this moment, i have flights with manual mode only with stabilization
blocks they were all successful. And also i have tested the vertical
navigational controller for altitude hold and climb modes. They were
successful too. But i have no chance to test hovering and navigating
horizontally. I am expecting the multirotor to fly between waypoints with
straight lines and hover at some horizontal points. I had achieved that
kinds of flights with Apm 2.5  4-5 months ago. I hope i can make it with
paparazzi too because i believe paparazzi project have a stronger structure
than the other open source projects. I am looking for someone who had
achieved flights like this to encourage me :)  Thanks for the answer..

Kadir


2014-02-13 21:22 GMT+02:00 Noah Martin <address@hidden>:

Hi Loïc ,
Il faut qu il fasse une recette aussi.
On peut lui envoyer un log d une mission photogrammétrie  avec les
coordonnées des waypoints associés ainisi que le bloc.
Walid
Le 13 févr. 2014 16:31, "Kadir ÇİMENCİ" <address@hidden> a
écrit :

Hi ,
I need some help :) Im looking for someone to share experience with
multirotor flights with paparazzi . It will be great if  i can find a
flight data/log with waypoints autonomously. Thanks for any help in
advance..

Kadir


2014-02-12 14:54 GMT+02:00 Kadir ÇİMENCİ <address@hidden>:

Hello everyone,

I have noticed that the feedbacks about the flights with multirotor
frames are so weak. I cannot find any flight log/video/kml etc. except for
some ardrone flights with paparazzi on youtube. I am preparing to my first
flight with Paparazzi on LisaM v2.0 with a quadrotor but can't find any
refernce flight. Can you please share with any flight experience with
multirotors?

Thanks ,
Kadir

_______________________________________________
Paparazzi-devel mailing list
address@hidden
https://lists.nongnu.org/mailman/listinfo/paparazzi-devel

_______________________________________________
Paparazzi-devel mailing list
address@hidden
https://lists.nongnu.org/mailman/listinfo/paparazzi-devel

_______________________________________________
Paparazzi-devel mailing list
address@hidden
https://lists.nongnu.org/mailman/listinfo/paparazzi-devel

_______________________________________________
Paparazzi-devel mailing list
address@hidden
https://lists.nongnu.org/mailman/listinfo/paparazzi-devel

_______________________________________________
Paparazzi-devel mailing list
address@hidden
https://lists.nongnu.org/mailman/listinfo/paparazzi-devel

_______________________________________________
Paparazzi-devel mailing list
address@hidden
https://lists.nongnu.org/mailman/listinfo/paparazzi-devel

--
Erstellt mit Operas revolutionärem E-Mail-Modul: http://www.opera.com/mail/

_______________________________________________
Paparazzi-devel mailing list
address@hidden
https://lists.nongnu.org/mailman/listinfo/paparazzi-devel