HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jul 31, 2009, 02:24 PM
Registered User
Greece, Attica, Piraeus
Joined Jun 2004
1,133 Posts
Well that was it.
I have perfect gps reception now with the antenna firmly attached and i also spotted and fixed another problem.
When the throttle goes above 60% interference starts to build and the gps
looses the signal and sometimes it halts operation.
I verified that this was coming from the ESC and a nice common and differential mode filter fixed that (i had it ready as i was suspecting the ESC also)
but i think the best solution would be a separate battery for the autopilot.
Chris
hendrix is offline Find More Posts by hendrix
Reply With Quote
Sign up now
to remove ads between posts
Old Jul 31, 2009, 02:50 PM
David1
bmw330i's Avatar
USA
Joined Mar 2007
1,478 Posts
Quote:
Originally Posted by hendrix
Well that was it.
I have perfect gps reception now with the antenna firmly attached and i also spotted and fixed another problem.
When the throttle goes above 60% interference starts to build and the gps
looses the signal and sometimes it halts operation.
I verified that this was coming from the ESC and a nice common and differential mode filter fixed that (i had it ready as i was suspecting the ESC also)
but i think the best solution would be a separate battery for the autopilot.
Chris
I wonder, how then would the autopilot know the battery level? Is there some way? -David
bmw330i is offline Find More Posts by bmw330i
Reply With Quote
Old Jul 31, 2009, 03:04 PM
FREEdom!!
Joined Feb 2006
294 Posts
There are voltage/current sensors that you can buy and easily attach to an available ADC.
Buzz_Lightyear is offline Find More Posts by Buzz_Lightyear
Reply With Quote
Old Jul 31, 2009, 03:16 PM
Registered User
Greece, Attica, Piraeus
Joined Jun 2004
1,133 Posts
Yes a spare adc channel can be used or you can use a DC filter.
I need to do some more tests but i think i already know that it works fine
as i have use it with great success in my FPV plane in order to eliminate the video noise.
In this case no modification is needed.
I also want to say again that the problem i had was in fact two separate problems.
Soldering the gps antenna while applying pressure to it fixed the gps reception while on the ground and air for sure as the difference was remarkable.
Then i noticed that when i applied more than 60% throttle whether in MANUAL mode or in AUTO2 the gps was starting to lose sensitivity and above 90% it would stop receiving and some times halt (freeze).
I did verify this many many times and i fact i was very happy that at last i definitely found the causes of my gps troubles.
Chris
hendrix is offline Find More Posts by hendrix
Reply With Quote
Old Jul 31, 2009, 10:32 PM
Registered User
USA
Joined Nov 2004
90 Posts
How hot does the 5V regulator gets on the TWOG/Tini? When I have my TWOG in the EasyStar (on the ground, no airflow) it does get pretty hot, I have not measured the temperature yet, but I can keep my finger on it for only 4-5 seconds.

I do not use the TWOG to power any servos, I use a separate power supply for that (BEC). So the only offboard devices powered from the TWOG are the IR sensors, GPS and Xbee 50mW modem.

Just want to check if this is normal.

Thanks,
Vassilis
vassilis is offline Find More Posts by vassilis
Reply With Quote
Old Jul 31, 2009, 11:24 PM
Registered User
Greece, Attica, Piraeus
Joined Jun 2004
1,133 Posts
Quote:
How hot does the 5V regulator gets on the TWOG/Tini? When I have my TWOG in the EasyStar (on the ground, no airflow) it does get pretty hot, I have not measured the temperature yet, but I can keep my finger on it for only 4-5 seconds.
Make sure that the bec +5v and the onboard +5v rail do not make any contact.
It sounds like the on board regulator and the BEC have their +5v outputs in parallel.
Meanwhile here are three more photos.
Chris
hendrix is offline Find More Posts by hendrix
Reply With Quote
Old Aug 01, 2009, 01:42 PM
Registered User
Joined Apr 2009
2 Posts
Problems in AUTO2

Hey Guys,

David and I need some help. He wrote some stuff on here a few days ago regarding our plane (Multiplex Mentor) working fine in Manual and Auto1, but seems to be trying to go counterclockwise instead of clockwise when in Auto2. We are kinda stumped on what it can be. The servos are working correctly in Manual and Auto1, and the IR sensors are also working correctly.

I attached the log file from today's flight and my code. Please help us out because I only have a couple days left to figure this out.

Thanks.
Armen
armz12 is offline Find More Posts by armz12
Reply With Quote
Old Aug 01, 2009, 02:00 PM
Registered User
Greece, Attica, Piraeus
Joined Jun 2004
1,133 Posts
Can you be a little more specific?
What do you mean "counterclockwise"?
If you want the plane to do circles clockwise use this in your flight plan:
<set value="DEFAULT_CIRCLE_RADIUS" var="nav_radius"/>
and if you want to make circles counter clockwise use:
<set value="-DEFAULT_CIRCLE_RADIUS" var="nav_radius"/>
I will be looking the file posted but can you be a little more specific with the problem you have?
Chris
hendrix is offline Find More Posts by hendrix
Last edited by hendrix; Aug 01, 2009 at 02:02 PM. Reason: typos
Reply With Quote
Old Aug 01, 2009, 02:37 PM
Registered User
Greece, Attica, Piraeus
Joined Jun 2004
1,133 Posts
I am surprised that it flies.
You have the IR set wrong and subsequently you were forced to reverse
the aileron servos.
In the beginning of your flight in manual mode you turn right but the PFD shows that you turn left!!!!
The IR messages show that you have the lateral axis reversed.
change this: <define name="IR1_SIGN" value="1"/>
to that: <define name="IR1_SIGN" value="-1"/>
What you need to do is to make sure that the right hand IR sensors when looking the plane from behind (you have the IR XY head tilted) give positive readings in the IR messages (Open the messages server and click the "IR_SENSORS" messages)
when you touch their window with your finger and that the left hand sensors give negative readings.
when you touch the right front IR sensor the "int16 lateral" should be positive (~200) and when you touch the right back sensor the "int16 longitudinal" reading should be positive.
Here is what the wiki says:
In the tilted case, the sensors are tilted by 45 degrees; ir1 is along rear-left -- front-right, and ir2 along rear-right -- front-left.
Also make sure that the Z IR head give positive reading when you touch the sensor that looks down.
If you need to change polarity edit and add "-" to the definition that needs to be reversed:
<define name="IR1_SIGN" value="1"/>
<define name="IR2_SIGN" value="1"/>
<define name="TOP_SIGN" value="1"/>

Go out when you are sure you got it right and hold the plane with your hand above your head and in a way that the IR sensors cannot see you and with the nose of the plane pointing away from you.
Now roll the plane with your hand say to the right.
Does the PFD shows that the plane rolls to the right?
Be careful, the brown part of the artificial horizon should go up from the right side and the horizon line should be tilted to the left.
Does the "int16 lateral" message shows a positive reading?
If yes then pitch the plane say to the sky.
Does the PFD show that you are climbing?
Does the "int16 longitudinal" message gives a positive reading?
If yes then you can proceed with the servo setup.

What i do when i set up the servos:

1) First make damn sure that the IR sensors are setup correctly by
examining the IR messages
of the GCS
(read the IR setup in the wiki and especially what readings should every
individual sensor give)

2) make sure that the radio file correctly describes the servo order
that the rx outputs
and all servos have their min=1000 and max 2000 microseconds.
Exact values are not that critical but the min value must be on the low
side and the max value
at the high side. The min and max values must be the same as the ones in
the airframe file.
All that should give me a good starting position.

3) Place the autopilot in AUTO1 mode, take the plane in an open space and
check if the control surfaces move to correct the plane's attitude
when i roll and pitch the plane with my hand and without moving any tx
stick.
If a servo is moving the wrong way i reverse the servo min/max values at
the servo section of the airframe file.

4) Then i go into MANUAL mode and i check if the control surfaces move
the correct way when
i move the sticks.
If a surface does not move the correct way i just reverse it at the tx side.
To my eyes reversing a servo from the tx is like holding the tx upside
down or sideways,
the autopilot should not care at all how i hold the tx.

I am not a Guru and i could be wrong so if someone can correct my
procedure i would be glad.
Chris
hendrix is offline Find More Posts by hendrix
Last edited by hendrix; Aug 01, 2009 at 04:03 PM.
Reply With Quote
Old Aug 01, 2009, 03:16 PM
Registered User
Panama', RP
Joined Aug 2004
65 Posts
Problems in AUTO2

Hi All,

The files that David and Arman are using are for My Mentor. They work in all modes. The IR orientation that I use is here :

http://paparazzi.enac.fr/wiki/Previous_Infrared_Sensors

This orientation gives signs of 1 which are in fact the default settings. I worked hard some time ago to come up with the orientation to get something a kin to the arrows and the up indicator that FMA uses on their sensors. I started my installation on this note and went from their. The aileron servo directions depend on wether you have the arms both pointing to the center or outward.

Hope this helps explain how I came up with the files that I used.

Joe
joekadet is offline Find More Posts by joekadet
Reply With Quote
Old Aug 01, 2009, 03:25 PM
Registered User
Greece, Attica, Piraeus
Joined Jun 2004
1,133 Posts
Hi.
It depends how you mount the IR sensors as there are many ways to mount them.
There is no error in the files but some adjustments are needed from installation to installation in order to compensate for the placement of the sensors, the servo arms etc.
When i replayed the flight i run the message server from the GCS and clicked the IR_SENSORS messages.
Then i saw except from the PFD screen that when the plane rolls to the right thus the right hand sensors see the ground and should give a positive value to "int16 lateral" instead they give a negative reading and vice versa.
I think i am right on this one but if anyone has a different opinion please jump in.
Chris
hendrix is offline Find More Posts by hendrix
Last edited by hendrix; Aug 01, 2009 at 03:43 PM.
Reply With Quote
Old Aug 01, 2009, 04:02 PM
Registered User
Joined Apr 2009
2 Posts
OMG I can't believe it! This whole time I thought it was correct. I was looking at the white line turning right and left instead of looking at it like it's a horizon.

Thanks a lot guys. We're going to fly tomorrow morning so I'll let you know how it goes.

-Armen
armz12 is offline Find More Posts by armz12
Reply With Quote
Old Aug 01, 2009, 04:15 PM
Registered User
Bergen, Norway
Joined Oct 2008
45 Posts
Hello,

Although having built and flown RC planes for many years I am a newbie to UAV . I have ordered hardware for the Paparazzi project (TWOG, GPS, modems) and I have a dedicated laptop with Ubuntu Linux 9.04 on board. I have downloaded the Paparazzi software sources and compiled the programs successfully. The GCS runs as expected in Simulation.

I have some computer and electronics experience, but I am rather new to Linux.

I am sorry if this is a stupid question, however in the last update to Ubuntu the following two items were labelled “Other”:

ivy-python (27KB)
paparazzi-dev (common support, 1KB)

I worry about doing damage to already working parts of the Paparazzi package, therefore I have not downloaded the updates yet. Could anyone please advise what is right to do?

Thanks,
Helge.
Hwal is offline Find More Posts by Hwal
Last edited by Hwal; Aug 02, 2009 at 02:28 AM.
Reply With Quote
Old Aug 01, 2009, 04:49 PM
Gaftopher
Gary Mortimer's Avatar
Nottingham Road South Africa/Bedford UK
Joined Feb 2007
3,628 Posts
This paparazzi thing is winning a competition right now..... http://www.diydrones.com/profiles/bl...age=5#comments ;-)
Gary Mortimer is offline Find More Posts by Gary Mortimer
Reply With Quote
Old Aug 02, 2009, 01:26 PM
Registered User
Greece, Attica, Piraeus
Joined Jun 2004
1,133 Posts
Quote:
I am sorry if this is a stupid question, however in the last update to Ubuntu the following two items were labelled “Other”: ivy-python (27KB) paparazzi-dev (common support, 1KB)
Hi.
Not a stupid question at all as i had the same question my self once.
This is related to the update process of UBUNTU.
It means that there are some new packages but they are not from the standard Ubuntu repositories (logical since they come from the paparazzi repository)
You can install them if you wish or leave things as they are.
Just install what the Paparazzi wiki says and you are fine.
Chris
hendrix is offline Find More Posts by hendrix
Reply With Quote
Reply


Thread Tools