If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #2431
Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639
Ok, ive got my generation 5 tri-copter working well, Ive already loaded it up with special cameras. Next ill be putting in humidity, pressure, temperature, CO2, CO, CH4, photometer, spectrometer and any other sensors i can think of.
The following pics are of a conventional RGB still camera and a modified NVDI cam. The NVDI cam is meant to reveal health --or lack of from photosynthetic life. NVDI varies from -1 to +1, so -1 to 0.1 is generally considered non-living. Above 0.1 to 0.9 is the useful range for evaluation from unhealthy (0.1) to very healthy (0.9), from 0.9 to 1 is questionable positive and should be remeasured.
Note: NVDI = Normalized Vegetation Difference Index
From left to right,"Infra Blue", false color and RGB
Color scale is: green = non photosynthetic, Blue = false return?, yellow = sort of healthy, red = really healthy. As an example of ultra low photosynthetic return, look at the drive way, tree trunk, and gravel. The barn shows some odd false returns.
Comparison, note the bright spot. These pics were all take after 2pm, here in California, winter. This means the sun was low and dim on the horizon. but at least i kept the behind the view of the cameras. Fortunately i remember the lens cap needed to be removed from all three cams this time, and they worked without quitting in the middle of a flight. Ive had both problems in the past.
Got up pretty high for this one, may go high tomorrow, note Mount Shasta at the very top-middle of the pic. Ill definitely fly with the sun as high as possible.
EDIT: I dont like the term "infra-blue", but it seems to be used commonly in this field.
Heres a final type of graphic id like to get: But i dont know how...(credit to "cfastie" of Public Lab, note his color scale.) He has given me a ".lux" file, but i dont know how to use it in GIMP.
Registered Member #96
Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4061
Sounds intriguing.
Someone at work was showing me their luxmeter/etc project and mentioned an actual lux sensor. I believe these are used in Iphone 4/4S/5/6 as well as some of the Samsung smart phones so old dead boards might be a viable source for both the pressure sensors and other goodies.
Other folks have been recycling the S4 MEMS microphones as wind direction/speed indicators as their high frequency response goes well above published specs. Have heard that 25 kHz is quite reasonable as a knee point on these.
Re. barn. Algae maybe? Wouldn't need to be a particularly thick layer methinks.
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
Scientific Measurements From Aerial Vehicle.
