Professional drone service company Ryka UAS inspected a monopole telecommunication tower in Washington, to assist in the design of a new antenna mount on the upper rad center…

Project Description

Using drones to inspect industrial structures is becoming a trend, not just due to the method’s low cost and efficiency, but also because of the lower risk incurred when compared to traditional inspection methods.

 

One monopole telecommunication tower on Vashon Island in Washington state is deemed unclimbable by a contracted tower crew, due to structural limitations.

 

In order for engineers to identify, analyze, and design a new antenna mount for the tower, a well known telecommunications company requested that Ryka UAS, a professional drone service company from Seattle, survey the tower and create a high-definition 3D point cloud of it.

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Data Acquisition

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In order to closely map this unclimbable tower, a professional quadcopter drone from Turbo Ace was used. The Matrix-E has a Sony A6000 camera and compatible Geo-Snap system from Field Of View LLC (a camera add-on which uses the onboard GPS/IMU to provide a stand-alone geotagging and triggering solution), and acquired 24.3-megapixel images with good geolocation quality.

 

The team manually flew the quadcopter around the tower, with a flight plan consisting of several vertical columns approximately 13 meters away from the tower.

 

Electromagnetic wave interference can be a challenge for operating near communication sites, but thanks to an experienced drone pilot, the team was able to fly close to the tower, capturing images with over 80% of overlap and getting a high ground sampling distance of 0.2 centimeters.

 

Roughly 400 images were taken, which provide detailed information of the antenna and the mount for inventory purposes.

 

 

A Matrix-E Quadcopter flying over the telecommunication tower
– Image courtesy of RykaUAS

Achieved Results

3D densified point cloud from Pix4Dmapper, displaying in details the upper part of the monopole communication tower 

 

 

It took less than a day to acquire the images and process them into a precise, dense 3D point cloud which focuses on the upper rad center mounts, wireless-panel style antennas, and associated mounts. The project engineer measured the mount brackets using the high-resolution images in combination with the LAS point cloud.

 

Pix4Dmapper outputs can then be seamlessly integrated with CAD software for final analysis. Within 2 to 3 days, Ryka UAS delivered final analysis results in CAD to its client.

 

 

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Pix4Dmapper output imported in a third-party CAD software for further analysis and design

 

 

“It was difficult to obtain a good result purely from automatic processing. The first attempt gave us three towers instead of one. The repetitive surfaces were due to the big difference of view angles and image content. Adding manual tie points helped resolve the issue and gave us the impressive final results.”
– Robert Erdt, Ryka UAS

Advantages of This New Technology

Traditionally, a crane crew would have been needed to inspect this tower structure, but at a much higher cost and with limited vantage points. Creating a 3D model of the tower with drones and photogrammetry software proved to be more efficient and more cost effective.

 

 

 

“Pix4Dmapper is an important tool for our company.  We have been thoroughly impressed with the overall functionality and quality of the results that have been generated as well as the commitment of Pix4D to make improvements in the software and its usability.  Beyond creating impressive digital representations of infrastructure,the software has endless applications for many other industries we work with. The powerful analytics functions and outputs, speed up our workflows and increased the efficiency for the engineering team.”
– Robert Erdt, Ryka UAS