inclinometre

[ecalis]

hi there,

i'm just about to gather informations of what it would take (and cost) to build an uav, so i'm not very experienced at all, but there was a problem that came to my mind: how do you guys measure the inclination?
surely, that is going to be some sort of triaxial sensor, isn't it?
the only triaxial inclinometres i've found on other uav-pages are quite expensive and hard to get, is there a way around?

thanks for your help! :)
ecalis

[Unterhausen]

you can use a 3 axis rate gyro in combination with a 3 axis magnetometer.

[ecalis]

alright, cheers

i heard about that solution, too
but do they stay calibrated for the entire flight time (10 to 15 minutes approx) even if the aircraft needs to perfom some manoeuvres?

would i need to set that up and if, is it quite complicated? i*m not too much into constructing microelectronics.. ;)

but thanks for the help!
ecalis

[wadiprawita]

Thermopile sensor (FMA co pilot), 19 $ each from digikey

http://www.nongnu.org/paparazzi/

regards

-doni-

[ecalis]

what are the infrared sensors like regarding precision?
if those infrared sensors actually work well, that would be the perfect solution! thanks a lot!

ecalis

[bbstriker]

hi there,

i'm just about to gather informations of what it would take (and cost) to build an uav, so i'm not very experienced at all, but there was a problem that came to my mind: how do you guys measure the inclination?
surely, that is going to be some sort of triaxial sensor, isn't it?
the only triaxial inclinometres i've found on other uav-pages are quite expensive and hard to get, is there a way around?

thanks for your help! :)
ecalis
Hi

BTA Autopiloting systems make BTA AS06 and AS07. These are genuine giro and barometric autopilots that do not rely on visual or infrared sensors. BTA autopilots work in all weather scenarios. The AS07 is solid state and is quite frankly amazing for $250. These autopilots are designed, manufactured and tested in Israel- a country with a geat deal of UAV/RPV experience and success. I've seen an awful lot of discussion on this forum about work and projects to seemingly acheive what you can buy in a 2.5 oz unit for $250!

Check out http://www.maxxprod.com/mpi/mpi-16.html

Hope this is of some help!

[kd7ost]

I have an 07. I asked them a year and a half ago about the GPS port. They didn't have it employed at that time. You just jogged my brain to go look and I see they now have the "pidgeon home" function employed. You can get that version with a GPS antenna. Of course this will not serve as a guidance device per se. It will get lock when you enable it and it will return back to that point if enabled.

I also wonder if the altitude feature is a real altitude lock feature? Most entry level units will control pitch by preventing changes in BP. But, if an error accumulates it will hold at that new pressure. Sink or Lift can cause the plane to gain or lose altitude and it will try to hold it there. I would ask them. I read the manual and it uses a BP sensor but doesn't really say if it will return the unit to the altitude it was enabled at in the event vertical changes occur.

Dan

[wadiprawita]

Thermopile sensor works very well in my experience (my current autopilot system is based on this). Still working on inertial version, will compare them when finished. But maybe you can ask to AntonK or Antoine (the creator of paparazzi), they have worked with both thermopile and inertial system.

thank's

-doni-

[ecalis]

i looked at the BTA autopilots and as far as I understand the page, the autopilot just uses GPS to bring the plane "home" under certain conditions, but isn't capable of following a previously entered GPS route, doesn't it?

this route-following namely is one of the things I would like to have in that project. :(

but cheers for the help anyway, guys!

doni,
those thermopile sensors sound good, especially because they aren't that expensive :)
is it possible for those sensors to "calculate inclination" or do they only know whether the plane is level or not?

[radiohound]

Thermopile sensor (FMA co pilot), 19 $ each from digikey

http://www.nongnu.org/paparazzi/

regards

-doni-

That's not such a great deal. How about $8.75 each (for four) http://www.scalerobotics.com/store/catalog

http://www.uavs.net

[wadiprawita]

Thermopile can calculate inclination, from my experience up to 50 degree. Please search document about this from search engine. I get one french document made by paparazzi guy (if I'm not mistake : infrared_calib_paper.doc). it includes kalman filtering too.

regards

-doni-