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Josh Levine did an excellent job of generating a large composite map of Copehill
Down from Google Earth. The final image was 6,912 x 4,864 pixels in size, with
the JPEG version being 30.909 MBytes and the PNG version being 53.515 MBytes in
size. Below is a reduced resolution version of the map (the full version would
lake a long time to download).
A magnification of the central region (shown above within a yellow box) of the
map, shown below, illustrates the high resolution one can obtain using Google
Earth for some regions on earth.
However, not all features are discernable from the Google Earth map. From the
superposition of a GPS track on the Google Earth map shown below, the deviation
seen around the middle of the image in walking from the car park (lower open
area) was caused by the need to bypass a barrier across the road. Each green dot
represents a data point taken each second.
The various overhead wires going from building-to-building are also not visible
in the Google Earth images, so we spent time locating all the overhead wires
(shown in thick yellow in the above image) we could, and have added this
information to our maps. Our conclusion on viewing a superposition of our GPS
tracks (shown in green) on the map with the location of overhead wires
identified is that the wires do not degrade the GPS location information in any
noticeable way. Basically, we do
Google Earth imagery is not up to date. In the image below with the
superimposed, green, GPS track showing where I walked, there are clearly a set
of containers at eight o'clock on the overall image of Copehill Down that have
since been moved to a new area. On 15th October, 2007, this was an open road.
The raw accuracy of the GPS location information is shown in the image below
where I used a high sensitivity u-Blox unit attached to a PC and walked within 1
metre of the walls of various houses and buildings, always remaining on the
outside. The thin green tracks show where I walked, clearly erroneously
indicating me moving into and out of some houses and buildings.
In the portion of the Google Earth image of the car park, we show the tracks for
a physically stationary u-Blox high sensitivity GPS receiver with the antenna
fixed on top of the roof of our car. The tracks, shown in green, are for a
period from 10:37:10 am to 12:59:37 am and the wander in the reported location
lies within a box shown below.
The potential exists to improve the accuracy of the location reported by a GPS
receiver through the use of the data from a fixed GPS receiver. This technique
is often referred to as " differential GPS" . This is ongoing work, and we hope
to be able to report on progress later.
We defined 92 locations from which to take a set of panoramic images using a
professional, 10 MPixel, Canon DSLR camera. Josh Levine and Chris spent from
just after 10:00 am to 4:30 pm generating many gigabytes of imaging information,
with all the images taken in the RAW format. The location coverage order is as
shown in the map above, with some locations turning out to be in out-of-bound
areas. The panoramic images from each location will be corrected for light
level, converted to
We identified the unique buildings and houses, and photographed the four sides
of each unique building. For example, below we show the front side of Building 6
(marked as " X" on the left in the map above) with me holding a Super A3 (or
A3+) sized copy of the map shown above. This information, together with the
detailed panoramic images, will help us (and others, such as MBDA) construct an
accurate, 3D, " synthetic environment" for Copehill Down. </
What were we not able to do?
All the above work took us longer than I envisaged. Tasks we did not have time
to perform were:
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mapping the signal coverage for GSM 900 and GSM 1800 phones
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mapping the signal coverage for WLAN 802.11 signals
We my need to rely on the construction of a 3D model to enable us to predict the
signal coverage we did not have time to measure.
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Plan the task to be performed in detail.
For example, we had drawn up a map indicating the route to be followed for the
close-to-building GPS mapping, simply showing the order in which to proceed from
building to building. In reality, we needed / wanted to walk round each
building, recording a GPS track. The detail of the walk then threw our plan into
a bit of disarray, requiring some ad-hoc planning which is no substitute for
more detailed p
An example of good planning, execution and versatility in the face of unexpected
obstacles was the panoramic imaging work. All the locations that could be
covered, were covered before 4:30 pm. Where Josh and Chris encountered "
out-of-bounds" areas not obvious from the Google Earth map, they made changes
and recorded them on the laminated map using an indelible ink pen.
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Everything takes longer than planned.
I thought the panoramic photography taken at 92 sites would be completed in
about 2 hours: three hours maximum. Well, in reality Josh and Chris paused only
to download massive amounts of data and grab a roll to eat, and worked solidly
from 10:00 am to 4:30 pm, being among the last to leave. I reckon I need to
double the time from the maximum I estimate to get closer to reality. We ran out
of t
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Be careful. Sometimes more haste leads to less progress.
I set the logging computer in the car to record GPS data, whilst using another
laptop to gather data on a walk around. Well, guess what. The laptop in the car
was set to sleep after 20 minutes when on battery power, so we only have 11
minutes and 30 seconds of time in which the logging data has been taken at the
same time as the data on the walk around. A little more thought and prepara
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The Army sniper was most interesting and professional.
He reckoned that the only way he personally would be able to detect another
sniper is through movement. This was our early strategy, but we started to have
doubts about our strategy when informed by other Army personnel that snipers do
not move. Thanks to Andy Wallace, the Project Leader for the MoD Grand Challenge
for arranging the presence of the sniper, and thanks to the sniper f
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Rehearse the plan.
We brought along a precision Leica GeoSystems Disto A5 laser-based distance
measuring unit, only to find the laser dot it projects to the distant location
could not easily be seen in broad daylight. This left us with trying to peer
down the sighting system, leading us to take more time than we had budgeted. We
had to drastically curtail our use of this instrument, and omit useful
information such as the dimensio
Another reason to rehearse the plan is that it is quite stressful getting
everything done by a Team in a limited time, and we are not even in a military
conflict situation!
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Don't believe the weather forecast.
The forecast was for rain and gusty winds (" military weather" , in Andy's
words). In fact, as can be seen from the photographs, we had lovely sunny
weather with some winds, thankfully.
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Work together where you can.
There is a huge amount of work to cover. We plan to trade some of the
information we have gathered for information, such as WLAN coverage, that we
simply did not have time to cover.
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Leave the car engine running if you are using a mains inverter.
We used a mains inverter to power our laptop logging GPS information in the car,
and did not run the engine. With only one car left in the car park, we prepared
to move out, only to find nothing happening since we now had a flat battery.
Thanks to Stephen Crampton for having jumper leads and providing us the power to
start our car. As folks jokingly commented, we would not have b
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Google Earth can provide surprising high resolution images,
almost to high altitude aircraft imaging quality. Unfortunately, many of the
images are out of date so you need to be careful when using these maps.
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We should have brought along more people
so I could have spent more time with the sniper, spent more time looking inside
the houses and buildings and spent more time seeing what the other Teams were up
to. Unfortunately, two of our Team members experienced last minute problems: one
had an urgent business meeting that he needed to attend, and the other was
caught up in a massive traffic jam. Having two reserve Team members who coul
Anyway, it was a tremendously useful day. We collected a load more information
that can be applied to the detection of military threats in any village. We will
be posting more results from our analyses to benefit those developing Unmanned
Vehicles for use in the detection of threats to military personnel and those
involved in the monitoring of installations of all descriptions, throughout the
world.
We are using the MoD Copehill Down village as a generic village in which to
exercise our threat detection strategies.
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Meeting at Barnard Microsystems Limited London office on 19
th
November, 2007
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From left to right, Lee Smiley from DESG, Joseph Barnard from Barnard
Microsystems Limited, Andy Wallace, the Project Manager for the MoD Grand
Challenge 2008 and Rob Frampton, from DSTL and a judge at the MoD Grand
Challenge 2008 at All Bar One in Crouch End, North London. Prior to this, we
discussed the Barnard Microsystems tactics and progress to date, and Andy
updated us all on what he had learned after a visit to the DARPA staff who have
been managing the DARPA Grand Cha
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EDA signs contract for development of anti-sniper system
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