How Do The PerfectFlite Altimeteters Work?

Discussion about deployment systems including altimeters, timers, air speed flaps, servo systems, and chemical reactions.
christheman200
WRA2 Member
WRA2 Member
Posts: 19
Joined: Mon Apr 21, 2014 10:07 pm

How Do The PerfectFlite Altimeteters Work?

Post by christheman200 »

Just wondering what kind of sensor(s) is used in the PNut altimeter.
I'm guessing it uses a radar altimeter, or does it use a GPS or barometric pressure sensor?
User avatar
bugwubber
WRA2 Member
WRA2 Member
Posts: 1087
Joined: Wed Dec 19, 2012 2:47 am

Re: How Do The PerfectFlite Altimeteters Work?

Post by bugwubber »

christheman200 wrote:Just wondering what kind of sensor(s) is used in the PNut altimeter.
I'm guessing it uses a radar altimeter, or does it use a GPS or barometric pressure sensor?
Almost all model rocket/hobby altimeters use barometric pressure sensors.
Bugwubber

Team S.P.E.W.
christheman200
WRA2 Member
WRA2 Member
Posts: 19
Joined: Mon Apr 21, 2014 10:07 pm

Re: How Do The PerfectFlite Altimeteters Work?

Post by christheman200 »

Thanks!
User avatar
bugwubber
WRA2 Member
WRA2 Member
Posts: 1087
Joined: Wed Dec 19, 2012 2:47 am

Re: How Do The PerfectFlite Altimeteters Work?

Post by bugwubber »

You betcha. (Working on my Minnesota accent)

Ran short on time, but wanted to followup with this-

GPS, The military won't let us use the accurate GPS signals. So GPS readings will always be purposfully quoted with large margin of error. Also, heavy.

The radar sounds like fun but perhaps a bit expensive and heavy.
Bugwubber

Team S.P.E.W.
User avatar
Water Rocket Expert
WRA2 Member
WRA2 Member
Posts: 622
Joined: Fri Nov 22, 2013 10:39 am

Re: How Do The PerfectFlite Altimeteters Work?

Post by Water Rocket Expert »

I am getting back to work, on my Ballistic Mail Missile.
Water Rocket Expert
I'm 20
Maryland
"Anyone who has never made a mistake has never tried anything new." -Albert Einstein
User avatar
U.S. Water Rockets1
WRA2 Member
WRA2 Member
Posts: 1778
Joined: Sat Feb 03, 2007 3:24 pm

Re: How Do The PerfectFlite Altimeteters Work?

Post by U.S. Water Rockets1 »

christheman200 wrote:Just wondering what kind of sensor(s) is used in the PNut altimeter.
I'm guessing it uses a radar altimeter, or does it use a GPS or barometric pressure sensor?
Nobody we know of outside NASA and maybe Armadillo Aerospace (and the like) use radar altimeters. They are just too bulky for a small rocket. As far as GPS is concerned, the accuracy is much lower in the vertical direction than it is in the horizontal direction. The PNUT we don't know for sure what it uses. Possibly an accelerometer? You can probably find out with a google search.
Team U.S. Water Rockets
Visit USWaterRockets.com
Visit our Blog
Tune in to our YouTube Channel
Visit our Facebook page
Visit our Twitter Page
Opportunity is missed by most people because it is dressed in overalls and looks like work. --Thomas Edison
User avatar
bugwubber
WRA2 Member
WRA2 Member
Posts: 1087
Joined: Wed Dec 19, 2012 2:47 am

Re: How Do The PerfectFlite Altimeteters Work?

Post by bugwubber »

U.S. Water Rockets1 wrote:
christheman200 wrote:Just wondering what kind of sensor(s) is used in the PNut altimeter.
I'm guessing it uses a radar altimeter, or does it use a GPS or barometric pressure sensor?
Nobody we know of outside NASA and maybe Armadillo Aerospace (and the like) use radar altimeters. They are just too bulky for a small rocket. As far as GPS is concerned, the accuracy is much lower in the vertical direction than it is in the horizontal direction. The PNUT we don't know for sure what it uses. Possibly an accelerometer? You can probably find out with a google search.
From the pnut manual obtained through a google search ;-)

"The Pnut utilizes a precision pressure sensor and 24 bit delta sigma analog to digital converter to obtain an extremely accurate measurement of the air pressure surrounding your rocket. "
Bugwubber

Team S.P.E.W.
User avatar
U.S. Water Rockets1
WRA2 Member
WRA2 Member
Posts: 1778
Joined: Sat Feb 03, 2007 3:24 pm

Re: How Do The PerfectFlite Altimeteters Work?

Post by U.S. Water Rockets1 »

bugwubber wrote:
U.S. Water Rockets1 wrote:
christheman200 wrote:Just wondering what kind of sensor(s) is used in the PNut altimeter.
I'm guessing it uses a radar altimeter, or does it use a GPS or barometric pressure sensor?
Nobody we know of outside NASA and maybe Armadillo Aerospace (and the like) use radar altimeters. They are just too bulky for a small rocket. As far as GPS is concerned, the accuracy is much lower in the vertical direction than it is in the horizontal direction. The PNUT we don't know for sure what it uses. Possibly an accelerometer? You can probably find out with a google search.
From the pnut manual obtained through a google search ;-)

"The Pnut utilizes a precision pressure sensor and 24 bit delta sigma analog to digital converter to obtain an extremely accurate measurement of the air pressure surrounding your rocket. "
It had to one or the other methods. Some altimeters seem to combine both methods as well.
Team U.S. Water Rockets
Visit USWaterRockets.com
Visit our Blog
Tune in to our YouTube Channel
Visit our Facebook page
Visit our Twitter Page
Opportunity is missed by most people because it is dressed in overalls and looks like work. --Thomas Edison