This isn’t Kansas Toto

Since we brought our system online last September, we haven’t had the opportunity, or need, to showcase our rapid-response capability.  That changed with the devastating set of storms that rolled into the deep-south on April 24^th, which spawned an EF4 tornado that was on the ground for an astonishing 149 miles!

On the Move

Once the debris settled into place, we quickly re-routed the system to Yazoo City, MS, which at the time was en route to Florida for a project with the DOT.  We picked Yazoo City because it was one the harder hit areas (the wedge funnel was over 1.75 miles wide in Yazoo City), and it presented the opportunity to perform widespread damage assessments.

  

Johnny on the spot

Five hours (and 280 miles) after re-routing the Mobile LiDAR system, we were on-site.  We’ve always said that the key to the system is mobility, and the ability to rapidly deploy for emergency situations.  When we rolled into town, we knew our response couldn’t have been any better when only the emergency management responders, local media, and storm-chasers were on the scene.  The picture to the right shows the remnants of Hillcrest Baptist Church and the devastation a storm of this magnitude can cause. 

For anyone that’s watched the Discovery Channel’s Storm Chaser’s television series, you’ll likely recognize Reed Timmons’ TVN “Dominator” tornado intercept vehicle in the below image.  Although the Dominator is built to withstand high winds and hail…we think our system looks better.

This is the first in a series of blogs showing information collected in the aftermath of the late-April tornado that devastated Yazoo City, MS.  Baker has had a long presence in Mississippi - our Jackson office is the second oldest in our firm at 60+ years.  Our thoughts are with those you have been impacted by this storm.

The Size of Data - Zettabyte?

I spent a few hours this past weekend helping my wife clean out our home office.  In all the clutter, she found a case for 3.5" floppy disks containing about 50 disks. While we perused the labels on the disk - HP Printer Driver Disk 1 of 3, GIS Topics (senior elective), endless blanks - we searched the house for a computer with a disk drive capable of determining the need to keep any of them.  Of the 3 computers in our home, we came up empty handed.  


After chatting a bit about the need to keep things we didn't even know existed in the first place, my wife relented and I threw them in the garbage.  Then I promptly removed them from the garbage. As my wife brought to my attention, the same person who's going to rummage through garbage to find personal information, probably has a drive that somebody else threw away. So, as I began destroying the disks, I contemplated the size of the data they contained.  After all, it's interesting to see how technology, and storage, has developed over the past years or decades.


Over the past 20 years, we've witnessed the size of data and what we store grow to astronomical levels - levels that even require the invention of new words.  From kilobytes, megabytes, gigabytes, terabytes, petabytes, exabytes to zettabytes - One zettabyte is equal to one million petabytes, or 1,000,000,000,000,000,000,000 individual bytes. (The yotabyte is next.)


To give you an idea of the amount of data we capture with the system, I've compiled a table presenting rates given the camera and laser frequencies:

Measurement Frequencies	50 kHz	100 kHz	200 kHz
Camera Rates
Cameras Off	3 MB per second	6 MB per second	12 MB per second
1 frame per second	13 MB per second	16 MB per second	22 MB per second
2 frames per second	23 MB per second	26 MB per second	32 MB per second
3 frames per second	33 MB per second	36 MB per second	42 MB per second

Looking at these numbers, it would take about 0.034 seconds to fill up one of those disks I threw away - when the system is working at peak performance. Our operators would need fast hands and a steady supply to keep up with the system. Thankfully, we have a constant supply of hard drives to transfer information from the vehicle to our processing facilities. 


With the advancements in computer processors, memory, video drivers and software, we have come a long way with what we're able to effectively manage.  The slide show prepared for Baker's 70th Anniversary provided me a glimpse of where we've been...  

I can't imagine processing Mobile LiDAR data with that computer - although it cost significantly more than the systems we use today.

Happy 70th Baker!  Here's to another 70!

It's Official: 3D is the New Standard

Growing up, I felt I was more fortunate than my brother when it came to not having to wear glasses (especially those hideous Army BC glasses).  Today when discussing glasses, I'm not talking in terms of optical power, but rather Anaglyph versus Polarized.

Movies and TV
Chances are you have likely seen a movie in 3D.  With the proliferation of Avatar and movies from Pixar there is a growing awareness and desire for 3D.  At 2, my son sat through Ice Age: Dawn of the Dinosaurs with his polarized glasses on the entire time.  Even now, if you have $2,500+ you can purchase a 3D DLP or LED television (3DTV).  There are announcements constantly about the progression of 3D channels to supply content to these devices.


The Internet
You may not have noticed a recent change to Google StreetView. To be honest, it took me by a little bit of a surprise. Below is a screen capture of the I-110 interchange I've discussed in this blog before.  Notice the new icon.  There have been many times where I have shown our Mobile LiDAR collection of this interchange in 3D using anaglyph glasses.

Mobile LiDAR
We have been presenting 3D animations and renderings of our Mobile LiDAR collections for quite some time.  (Below is the same expanse of the I-110 interchange as shown in the new StreetView.) Looking at 2D images does not provide a measure of depth that is afforded with this information.

Revisiting the Mississippi River Levee collection, I've created an image that can be viewed in 3D using anaglyph glasses.

I now wear glasses - not because of a loss of vision, but to gain perspective. 

If you would like a pair of anaglyph glasses to view the blog, send me your address and I'll mail you a pair.

Clouds - Not the Fluffy Kind

Following up on the "Question of the Day" post, I wanted to share a video that was produced of the I-110 collection in Baton Rouge.  The video was part of a presentation given earlier this week at the National States Geographic Information Council Mid-Year Conference in Annapolis, Maryland.

The collection consisted of 27 different approaches to the interchange and took about one and a half hours.  The dense collection of points is commonly referred to as a Point Cloud - Wikipedia has a limited definition.  The cloud shown in the video is composed of 491 million points.

Neither snow nor rain nor heat nor gloom of night...

With the recent snow storms impacting the country, I thought of no better topic than a discussion of weather and Mobile LiDAR.  It is relatively easy to work around localized weather events when utilizing a vehicle as opposed to an airplane or helicopter.  But sometimes, it's absolutely necessary to work in such conditions.

As discussed in earlier posts, LiDAR is an active sensor which uses a laser to measure distance to an object (same premise as total stations - traditional surveying instrument).  Therefore, our system can operate day or night and in virtually every weather condition.  We have several examples of night collections (Downtown Norfolk and I-85/285 in Atlanta), rain conditions (The Narrows - State College, PA) and now snow as shown below.

The image above was captured at our Beaver, PA office during snow flurries.  The image is colored by height to show all the snow in the scan (red dusting of points).  While the image below illustrates the same collection with the snow "cleaned" from the scan.  There are several different ways to accomplish this. But, it simply boils down to the intensity of the reflected light from the snow flakes and the elevation of those points.  Rain and snow each pose various processing challenges, but when you need information, sometimes it takes a little extra effort.