prinz@cod.NOSC.MIL (Robert A. Prinzivalli) (11/27/90)
I am a systems engineer (EE) who is attempting to help the
Kenya Wildlife Service (KWS) and Wildlife Conservation International
(WCI) with a technical solution to one of their more difficult problems.
The problem is how to detect and count elephants in a dense rainforest.
One method that is the current hot topic of debate is whether or
not infrared detectors would be able to detect the presence ofan elephants s
thermal emissions (at night?) throught a dense forest canopy. Since there
is no clear proof either way, we would like to conduct some tests to answer
this question once and for all.
We are considering two tests to be conducted at the San Diego Wild
Animal Park. The first test is simply to determine what the frequency of
any thermal emissions might be. Since this is not my area of expertise,
I would appreciate it if someone out there could tell me what type of
instrument would be best suited for this purpose; a bolometer, a radiance
spectrometer; a radiometer or what? Also, since the KWS and WCI have very
little money to spend on this project, could you tell me where I might be
able to rent or borrow (preferably borrow) such a device. The second test
would be conducted from a small aircraft with some portable instrument
capable of detecting emissions of the type and frequency determined in
the first test. Again, what type of device would be best and do you know
where I might rent or borrow one.
If anyone would like to volunteer their help you can answer via
arpanet or call me at the Naval Ocean Systems Center, San Diego at (619)
553 -3603.
Thanks in advance for any assistance you can give.
Bob Prinzivallilarry@kitty.UUCP (Larry Lippman) (11/27/90)
In article <2492@cod.NOSC.MIL>, prinz@cod.NOSC.MIL (Robert A. Prinzivalli) writes: > The problem is how to detect and count elephants in a dense rainforest. > One method that is the current hot topic of debate is whether or > not infrared detectors would be able to detect the presence of an elephants > thermal emissions (at night?) throught a dense forest canopy. Since there > is no clear proof either way, we would like to conduct some tests to answer > this question once and for all. > We are considering two tests to be conducted at the San Diego Wild > Animal Park. The first test is simply to determine what the frequency of > any thermal emissions might be. Assuming you have no offer of apparatus from the military :-), you can utilize industrial thermographic imaging systems. There are essentially only two wavelength ranges for detectors: 2 to 6 microns, and 8 to 12 microns (give or take a bit). My off the cuff opinion is that you might be better off with the long wavelength detector, but dual wavelength systems are also available. The short wavelength system will also function, however. Unless one uses external filters, industrial thermographic imaging systems are broadband within their respective wavelength range. You really don't have to worry about "tuning" for a particular wavelength. > Since this is not my area of expertise, > I would appreciate it if someone out there could tell me what type of > instrument would be best suited for this purpose; a bolometer, a radiance > spectrometer; a radiometer or what? You definitely want an infrared thermographic imaging system. Typical manufacturers are AGA, Inframetrics, Hughes Aircraft Industrial Products div., etc. > Also, since the KWS and WCI have very > little money to spend on this project, could you tell me where I might be > able to rent or borrow (preferably borrow) such a device. The second test > would be conducted from a small aircraft with some portable instrument > capable of detecting emissions of the type and frequency determined in > the first test. Almost all electric power utility companies use thermographic imaging apparatus for inspection of transmission lines, switchgear, transformers, etc. for hot spots and potential electrical faults. Larger utilities have systems which are mounted in helicopters or fixed wing aircraft for inspection of major high voltage transmission lines. Your project sounds to me like it may have "PR appeal" to an electric utility company. I bet that with a careful approach and some ingenuity, you could pursuade such a utility to provide the necessary apparatus on loan - perhaps even including the aircraft. With public pressure resulting from high electric rates, fossil fuel emissions and nuclear power issues, electric utilities need all the "good neighbor" press that can find! :-) Good luck, and happy elephant hunting! Larry Lippman @ Recognition Research Corp. "Have you hugged your cat today?" VOICE: 716/688-1231 {boulder, rutgers, watmath}!ub!kitty!larry FAX: 716/741-9635 {utzoo, uunet}!/ \aerion!larry
jws@thumper.mlb.semi.harris.com (James W. Swonger) (11/27/90)
If the background temperature is going to be high (like tropical) then it will be harder to see the elephants - not much thermal contrast. For your test, be sure to pick a hot night so you don't end up with a system which only works at the zoo. Night vision systems based on image intensification or with an active IR illuminator and operated by a spotter would probably be effective but I don't think a passive IR, automated system would. Some CCTV cameras may have enough sensitivity in the IR band to be useful with some modifications. If you can get a CCD camera and put a thermoelectric cooler on the back of the CCD you can push the thermal noise down. Then with an IR filter you have a cheapie mid-IR vision system (you will still probably want an IR illuminator for optional use). an IR illuminator for optional use).
chidsey@smoke.brl.mil (Irving Chidsey) (11/28/90)
In article <1990Nov27.133123.5370@mlb.semi.harris.com> jws@thumper.mlb.semi.harris.com (James W. Swonger) writes:
<
< If the background temperature is going to be high (like tropical) then
<it will be harder to see the elephants - not much thermal contrast. For
<your test, be sure to pick a hot night so you don't end up with a system
<which only works at the zoo.
<
< Night vision systems based on image intensification or with an active IR
<illuminator and operated by a spotter would probably be effective but I
<don't think a passive IR, automated system would.
<
< Some CCTV cameras may have enough sensitivity in the IR band to be useful
<with some modifications. If you can get a CCD camera and put a thermoelectric
<cooler on the back of the CCD you can push the thermal noise down. Then with an
<IR filter you have a cheapie mid-IR vision system (you will still probably want
<an IR illuminator for optional use).
The real kicker is "under the canopy". I don't think IR will work
as it will be blocked by the leaves in the canopy. To penetrate the canopy,
you will need something with a wavelength much longer than the typical length
of the leaves in the canopy.
Radar may work. The reflectivity of elephants is probably lousy,
but at reasonable ranges you may be able to find elephants by looking for
the height difference. If they are running, you may be able to use a
motion detection mode to separate the elephant return from the ground
clutter and the foliage clutter.
The other effect that might get thru the canapy is sound. But then
you need a quiet platform, a balloon or dirigible, not a light plane or a
helicopter. Sounds like an interesting project.
Irv
--
I do not have signature authority. I am not authorized to sign anything.
I am not authorized to commit the BRL, the DOA, the DOD, or the US Government
to anything, not even by implication.
Irving L. Chidsey <chidsey@brl.mil>richard@pegasus.com (Richard Foulk) (11/28/90)
> Some CCTV cameras may have enough sensitivity in the IR band to be useful >with some modifications. If you can get a CCD camera and put a thermoelectric >cooler on the back of the CCD you can push the thermal noise down. Then with an >IR filter you have a cheapie mid-IR vision system (you will still probably want >an IR illuminator for optional use). Most current video cameras are highly IR-sensitive. So much so, that they come with an IR filter behind the lens to reduce their IR sensitivity. -- Richard Foulk richard@pegasus.com
J.M.Spencer@newcastle.ac.uk (Jonathan Spencer) (11/28/90)
In addition to the netter who suggests you twist the arm of electricity suppliers, can I suggest you might ask someone such as the London Fire Brigade who use use thermal imagers for detecting bodies (live ones they hope) in collapsed buildings. These were used in the Mexico and Iranian earthquakes. Jonathan M Spencer =========================================================================== Mail : Computing Lab, University of Newcastle-upon-Tyne, NE1 7RU, England Phone : +91 222 8229 ARPA : J.M.Spencer%newcastle.ac.uk@cs.ucl.ac.uk JANET : J.M.Spencer@uk.ac.newcastle UUCP : !ukc!newcastle.ac.uk!J.M.Spencer ===========================================================================
ifaq570@ccwf.cc.utexas.edu (allen kitchen) (11/30/90)
As one who has used deep IR imaging for some time, let me advise that thick jungle growth will indeed block the IR before it can reach the detector. Using it in open terrain would be a good idea, but trees have always played havoc with my older equiptment. I could make a joke about how hard could it be, but I know how much space that jungle covers, so I'll skip it ;) allen