Cape Cod Tech - 2025-10-09

www.ese-llc.com/cctech2025-10-07

Cyndi Penny - 107 Licensed Drone Pilot - HR Degree - Drafting Degree

Thadd Eldredge - MA Registered Professional Land Surveyor, Certified Federal Floodplain Manager, Math Degree, Surveying Certificate, Toughest Nerd in Chatham

We work at a small Land Surveying, Geomatics Engineering, Mapping Firm in Chatham. We do offer Civil Engineering services, minor are in house and more substantial are subcontracted to other engineering firms.

What do surveyors do? We measure.

What do we measure with?

GIS - CAD - ROBOTIC TOTAL STATIONS - GPS/GNSS - LIDAR LASER SCANNERS - DRONES (PHOTO)

GIS - Geographical Information Systems

Maps with Data

Interactive & Answers Questions

Usually completed by municipalities, but we made a series:

ESE Webmap CC Tech

ESE Webmap Wellfleet with Zoning Answers

CAD - Computer Aided Drafting - The software is very powerful but not very flashy for a presentation.

ROBOTIC TOTAL STATIONS

We really need to start with the evolution of survey instruments.

The optical instruments were introduced in the late 1800s. These would measure angles - both a horizontal angle and a veritcal angle. For those of you wondering about the multiple solution issue, we record angles to the right. Vertical angles are all based with zero straight up and 180 straight down. ***There are times when measurements are recorded backwards or upside down, but don’t worry about it today.***

The older instruments - the Theodolites and Transits required distances to be measured by tape. Later they added DistoMats to these instruments so you could measure distance to a prism. All measurments had to be written in a field book and then calculated by hand. Who likes Trig? The Distance is on a slope, so use the vertical angle to calculate the horizontal and vertical distances. The vertical distance lets you calculate the elevation. The horizontal angle and the horizontal distance lets you use Trigonometry and Coordinate Geometry to obtain a coordinate. You can sit all day with a claculator and sort out hundreds of XYZ coordinates.

Then they added a laser into the system and added more technology. We added little computers called Data Collectors to the units, first by wire, now by Bluetooth. Recording data became faster and you did not have to write in a book. Still, it is boring standing behind an instrument - turn to the prism, enter the prism height, change the description, press a button, store the record, repeat. All the while, the other person, the one with the prism, gets to run around while you are stuck. The math is all calculated in the data collector - no need to sit all day with a calculator. (You still need to know what the computer is doing because of GIGO - Garbage In Garbage Out).

They then added Servo Motors to the instruments and now the robot follows the surveyor with the prism. It’s not seamless, but it means a One Person Crew or Faster with Two.

Mathwise, the Total Station is great for the short game. There’s a little error with the angles, a little error in the distances, and the further you go, the more these add up.

GPS / GNSS - Global Positioning Systems - Global Navigation Satellite Systems

So what? We all have GPS in our phones. It’s not that great but we all have it…

We use a GPS Unit as a Base Station that sends corrections to the GPS Unit(s) known Rovers so they can calculate coordinates within an inch (usually) and within a centimeter (sometimes). The same data collector connects to the GPS Unit and you can record it all.

There are a few different methods with real time results or post processed results. There are quick observations and long observations.

Mathwise, these do not have as good of a short game as the Total Station has. However, you can go miles (6 miles) without a substantial drop in the accuracy and you can go further (20 miles) with a slight drop in the accuracy.

We utilize the best of both worlds by merging the GPS and Total Station data into one network solution using a very cumbersome (without the benefit of a computer) set of calculations called Least Squares.

That equipment is all common. We’re here for the fun stuff - Lasers and Drones!

LiDAR - Light Detection And Ranging - or - Laser Radar is the use of lasers to create point clouds. Point Clouds? These are just a bunch of points in a 3d viewer. Video of ESE with NavVis.

As a by-produc of scanning, we get panoramic images. Veteran’s Field

What were we looking for with the Total Station or GPS? XYZ. What does the Scanner give us? Lots of XYZ. I have run AutoTopo where the GPS just locates as you walk or drive with the unit mounted. I have gotten maybe 10,000 points in a day. The scanner produces hundreds of millions of points. You then have to be a Virtual Surveyor to get the right points out. Don’t worry about that part for now.

In 2014 we acquired the first Mobile Mapper in New England. ScannerJammer

DRONES - We are not brave enough to fly drones with LiDAR. We have lost 3 drones - 1 to a bad tree - 1 to a bad blade - 1 to a bad bird. We also like the higher quality LiDAR you get from the ground. We do have photo drones.

PLANNING - CONTROL - FLIGHT - PREPROCESSING - PROCESSING - QAQC - ARCHIVE - USES

Planning - Where? What are the obtacles and restrictions? President or Vice President nearby? No flights. Netflix series being filmed nearby? No flights. Bad weather with wind? No flights.

Control - We need ground control points. We get to spray paint checkerboards all over.

Flight - The software takes over because good photogrammetry requires consistent overlaps in the images.

Preprocessing - Find targets in images and point the program to the XYZ coordinates.

Processing - A Big Computer with a Big Video Card performs hours to days of processing to get the results.

QAQC - Did it work? Quality Assurance Quality Control. We check the orthomosaic against some saved data.

Archive - Put the files away for use.

Uses -

Orthomosaic - A Big Image combining all of the images acquired. Linnell Beach

Point Cloud - What? But there is No LiDAR. Yes, but the computer sorts out where the drone was when it took each picture and it sorts out the roll - pitch - yaw. When it can identify the same pixel in three images, it can compute a XYZ position of the pixel. Homogeneous surfaces are awful, water gets angry, wind makes trees disappear, but the right objects during the right conditions come out almost as well as a scanner.

Chatham Works Video

We have gotten into 3d modeling proposed buildings in Sketchup, then adding them into the Clouds and making videos.

99 Uncle Alberts

Interested in a career in Surveying? The nearest school offering in person and online degrees is UMaine Orono.

MALSCE - the Massachusetts Association of Land Surveyors and Civil Engineers Education Trust offers Scholarships to Massachusetts Residents. I am the Chair of the Education Trust. I don’t play favorites but my Board is ready to give money to Surveying Students.

We take one Intern for a paid position every Summer. Resumes can be sent to office@ese-llc.com.

Want to learn a little more without the commitment of a Summer? We can come back to your class, we can have field trips with survey gear, or we can offer conversations.

Other Videos in the Background with Questions in the Foreground

Monomoy Flagpole - Daughter had a task to measure the flagpole using geometry. I might have brought out the scanner to measure it in several ways…

Kendrick Road, Chatham - A dune nourishment project underway.

Downtown Chatham - Just a cool video using Elevation and Intensity.

Middle Road Solar Array - This was all modeled during permitting.

127 Christopher Hardings - A project that was not approved even though they saw the video.