• Hammer Missions

Drone Facade Mapping & Inspection - A step-by-step Guide.

Updated: Sep 16




Overview


Facade Mapping & Inspection have always been challenging, especially when your subject is a tall structure or building, so what options are there to overcome this challenge?


Generally, the default option used to be scaffolding or a cherry picker but this came with its own challenges - Scaffolding is expensive and takes time to construct and take down, and you have to rely on a scaffolding team to install the scaffolding around your structure or building. Cherry pickers are also expensive and they can't always reach the areas that you may need to inspect.


This is where using a drone to perform your facade mapping or inspection comes in.


Drones have changed the game. Not only can you reach hard-to-access areas in a fraction of the time, but you can also record and capture high-resolution images of the building facade. These images can be later used to analyse the facade's condition collaboratively in an office environment.


In this post, we will discuss the step-by-step drone workflow to inspect a building facade.


We will be looking the exact setup (hardware and software) we used and the end deliverables that were produced.

Mission & Requirements


In this mission, our goal was to capture and analyze one of the facades of an old abandoned Mill. This Mill is located at Robertsbrige, UK and our goal was the inspect the facade on the far side of the building.



Target Facade for Drone Inspection
Target Facade


Data Quality Requirements:

  • 90%+ of the facade captured

  • 80% overlap between images

  • Images in Focus and devoid of blur

  • Efficient & Repeatable Workflow


Deliverables

  • 2D Facade Images as per quality requirements.

  • Geolocated, Annotated Images.

  • 3D Model of facade (optional extra).

  • Web Link to the Project, viewable on a web browser.

  • PDF Report with detected issues.





Setup


For this drone-powered facade inspection mission, we used a DJI Mavic 2 Pro and an iPad with the latest version of the Hammer Missions App.


DJI Mavic 2 Pro with Hammer Missions App
DJI Mavic 2 Pro with Hammer Missions App

The DJI Mavic Pro 2 is highly portable and produces detailed-enough photos from its 20 Megapixel sensor, more information on why sensor sizes and megapixels matter in drone photography can be found in our post.


Camera Specs & Megapixels - Do they matter for Drone Photogrammetry?



Planning the Mission


  • We used Hammer Hub to locate the building to perform the Facade Mapping.

  • Selected the (+) icon in the top right-hand corner.

  • Selected the Facade Mapping mission for continuous capture.

  • We planned the mission by create points down the facade of the target building .


Creating a Facade Mission in Hammer Hub
Creating a Facade Mission in Hammer Hub

  • Estimates for altitude and distance from target were then adjusted within Hammer Hub by clicking the small gear icon. (These can be changed from the Hammer App when you are in the field)


Configuring a Facade Capture in Hammer Missions
Configuring a Facade Capture in Hammer Missions


Download The Mission To Hammer App


Before heading out to the field we downloaded the planned Facade Mission to the Hammer App

  • Then, we opened the Hammer App

  • Within the mission files section, selected the cloud option at the top of the screen

  • This then downloaded the mission from Hammer Hub to the Hammer App



  • You can also simulate the mission before you head out to the field. You will see the altitude change in the simulation to emulate the altitude change in the field.



On Site Settings


Once on site you can calculate the correct altitude and distance to target to ensure safety and mitigate any risk. We did this to ensure that our all mission parameters are correct.

Ideally you would initially take the drone up prior to using Hammer Missions and take the readings from the altitude at the top of the structure and from as near to the bottom of the structure as you can.


It is also advisable to check the distance to target to make sure your estimates are correct before you use automated flight.


Once you have done this you can open the Hammer App and make the adjustments.




Capturing The Data


After making the relevant adjustments so that we were happy with the distances, we went ahead and launched the drone to start the data collection.


We set the drone up in a safe area to take off and pressed the play button in the Hammer App. The video below demonstrates our live Facade Capture capture at the target building and will go through the whole process from take off to landing.




Verifying The Data


Once the flight has completed you can, if you wish, verify the data before you leave the site. You would need to remove the memory card from the drone and check the data on your laptop to make sure you are happy with the results and that all data has been captured correctly and is in focus.



Upload Data to Hammer Hub


Now we had collected the data and verified it in the field we started the process of uploading it to the Hammer Hub for data analysis.

  • Opened Hammer Hub. On the left pane > selected Data Analysis

  • Then selected 'New Project' in the top right corner

  • We put in a title and type for the project.


Creating a Data Project in Hammer Hub
Creating a Data Project in Hammer Hub

  • Then, pressed continue and chose our images from the job site.


Uploading Images in Hammer Hub
Uploading Images in Hammer Hub

  • Now that images were selected, we uploaded those images to Hammer Hub.

  • This is done by pressing the Create Project button. This will start the process of uploading your images


Uploading Images in Hammer Hub
Uploading Images in Hammer Hub

  • Dependant on the amount of images this can take some time.

  • This is a good time to make a cup of your favourite hot beverage and ensure that all flight logging and mission planning data was logged and captured from the flight!



Process The Data Into A 3D Model


Once the data was uploaded, we decided to process it into a 3D Model using Hammer Hub for additional context. To do this:


  • Open the Project

  • You will see that you now have all of your images and a mini map on the right hand side with your selected picture on the left.

  • Select the Process button in the top right corner


Processing Images in Hammer Hub
Processing Images in Hammer Hub
  • Dependant on the amount of images this can take some time.

  • You will typically be notified by email when you 3D model is ready.



Viewing the 3D Model


Once the data has been processed, it will be viewable as a 3D model.



We then draw annotations on our 3D model to mark areas that may need specific attention.

  • On the picture that corresponds with the correct part of the 3D image hold down the shift key and draw a box around the specific area in question.


Annotating Images in Hammer Hub
Annotating Images in Hammer Hub

This will give you the option to add a note to that specified annotation.

💡 All the notes and annotations are saved with the project, so if you were to share the project, all annotations will be shared as well.

Annotating Images in Hammer Hub
Annotating Images in Hammer Hub

Sharing and Creating Reports


Once we were done annotating, the project was ready to be delivered. To do this, we simply shared the project with clients, stakeholders, fellow team members by inviting them to Hammer Hub or sharing a private link to the project. You can also then generate PDF reports on the project.

  • To share the project, select share in the top right-hand corner.


Sharing Images in Hammer Hub
Sharing The Project from Hammer Hub

  • From here you can share with team members or share with clients and stakeholders via a generated link.

  • To generate a report select Report from the top right-hand corner

  • From here you can format and generate a report on your findings.


Generating a report in Hammer Hub
Generating a report in Hammer Hub

Conclusion


In this guide, we detail the steps we undertook to perform a drone-based facade inspection project with the aim of satisfying specific requirements on data quality, workflows and deliverables.


Curious to see the results for yourself? Here's a link to the project: https://hub.hammermissions.com/s/dpp_1582c1426f204f1ab14f176f1af0642b

Summary


We hope this guide helps you understand the typical workflow behind a drone facade inspection and how to process the collected data.


If you haven't got a Hammer account and would like to try Hammer Missions you can get started on our free trial.



If you'd like to learn more about how to capture high-quality data and get the most out of your drone flights using our cloud-based platform, please feel free to visit our learning resources.


To learn more about our enterprise solutions, including mission collaboration, data processing, and AI solutions, please contact us at team@hammermissions.com.


We look forward to hearing from you.


— Team at Hammer Missions









Recent Posts

See All

For more articles, subscribe to our monthly newsletter!

Thanks for subscribing!