Location
Eyrarbakki
About
About Me:
Electrical Engineer and Computer Scientist
Please tell us a bit about your UAV interest
Arducopter and Arial Photography.
Hometown:
Eyrarbakki
Activity Feed
"I am not trying to attenuate anything in the signal
But effectively you are. And theoretically you have to in order to prevent aliasing in you 1/40 decimation stage.
"
But effectively you are. And theoretically you have to in order to prevent aliasing in you 1/40 decimation stage.
"
"O.k. so basically you are using 200 tap mean filter for the decimation.
That filter gives you approx -45dB attenuation in the stop band. You can actually do much better with 200 taps filter, easily reaching -80dB attenuation in the stop band.
The…"
That filter gives you approx -45dB attenuation in the stop band. You can actually do much better with 200 taps filter, easily reaching -80dB attenuation in the stop band.
The…"
"Aliasing is hard (almost impossible) to deal with (except by raising the sampling rate).
Do you have any details on the decimation filters you are using?
I guess you are measuring the closed loop response, i.e. with the PID controller active?"
Do you have any details on the decimation filters you are using?
I guess you are measuring the closed loop response, i.e. with the PID controller active?"
"I noticed that the ESC driving the APM gets hotter in my setup.
Now I run the APM on a separate powersupply."
Now I run the APM on a separate powersupply."
"Got all the components and inserted one filter in the z gyro channel, channel 0.
The effect is quite noticeable. Compare the first animation in the original post to the new animation here.
Note the scale is little different. Side lopes outside of…"
The effect is quite noticeable. Compare the first animation in the original post to the new animation here.
Note the scale is little different. Side lopes outside of…"
"Here are some interesting results for the accelerometers. I am using ch4 in these images but they all (4,5, and 6) behave the same way. All the data is sampled at 4000Hz, one channel at a time.
So in the first animation and picture is…"
So in the first animation and picture is…"
"Interesting links JMD45.
Just a quick note. The reason why there is no difference between pictures 1 and 2 above, is that I accidentally overwrote my data file with data from another channel.
The capacitor does have effect on the bandwidth as is…"
Just a quick note. The reason why there is no difference between pictures 1 and 2 above, is that I accidentally overwrote my data file with data from another channel.
The capacitor does have effect on the bandwidth as is…"
"On page 14 in the manual for the Z-Gyro I found this clause
"If the AutoZero function is not used, the AZ pin ( pin 24) should be connected to ground."
It looks like the AZ pin unconnected on the Eagle files I have. What effect will it have to…"
"If the AutoZero function is not used, the AZ pin ( pin 24) should be connected to ground."
It looks like the AZ pin unconnected on the Eagle files I have. What effect will it have to…"
This is a followup to the aliasing discussion in http://diydrones.com/forum/topics/arducopter-drift-issuesHere is a short summary of the analysis done by us regarding the aliasing possibility.Same as before click on the images below to get the…
"Looked at the Oilpan in eagle. There the lowpass filter is set at 750ohm against 0.1uF, i.e. a 1st order lowpass filter with -3dB at 2.1 kHz. That means a minimum of 4.2kHz sampling.
So I went for the soldering iron and augmented the z-gyro channel…"
So I went for the soldering iron and augmented the z-gyro channel…"
"Spent some time on properly analyse the data sampled from the gyros. I tuned the ADC library to allow 2000 Khz sampling and wrote a simple program to collect the data for various motor speeds. As we can see from this data then there is considerable…"
"Jason,
There was a discussion earlier this winter regarding noise in the gyros.
I believe that I showed then that there is aliasing in the sampling of the gyros, i.e. the built in lowpass filter of the gyros is far from beeing strong enough and/or…"
There was a discussion earlier this winter regarding noise in the gyros.
I believe that I showed then that there is aliasing in the sampling of the gyros, i.e. the built in lowpass filter of the gyros is far from beeing strong enough and/or…"
"Man the formatting was messed up. The folder layout should be:
Change from
trunk/ProjectA
trunk/ProjectB
trunk/libraries_for_A_and_B
to
trunk/ProjectA/Application
trunk/ProjectA/libraries
trunk/ProjectB/Application
trunk/ProjectB/libraries
"
Change from
trunk/ProjectA
trunk/ProjectB
trunk/libraries_for_A_and_B
to
trunk/ProjectA/Application
trunk/ProjectA/libraries
trunk/ProjectB/Application
trunk/ProjectB/libraries
"
I have been following the release of Arducopter 2.0.x.There are few things I have noticed that I think should be fixed for better tracking of bugs and better release management.1) Libraries in svn are shared between many distinct projects.a) This…
"jasonshort wrote:
"There was an issue in 2.0.7 if you had Yaw_I set to anything but 0. please re-download it or set it to 0 in the config tool.
Jason"
The cost of increasing version number approches zero while the cost of confusion because of two…"
"There was an issue in 2.0.7 if you had Yaw_I set to anything but 0. please re-download it or set it to 0 in the config tool.
Jason"
The cost of increasing version number approches zero while the cost of confusion because of two…"
"It would be so cool if the .svn folders was not distributed with the .zip files.
svn export is your friend."
svn export is your friend."
