Optimise your In-field Registration Workflow with Leica Cyclone FIELD 360

The foundation for producing exceptional reality capture deliverables resides in the acquisition of high-quality 3D scan data. Utilising robust laser scanning software, such as Leica Cyclone FIELD 360, empowers users to capture accurate data, facilitating the immediate creation of deliverables. One specific functionality that plays a pivotal role in this process is in-field registration. 

In this expert insight, Simona Hriscu, Senior Product Engineer in the Reality Capture division of Leica Geosystems, explains the latest release of Cyclone FIELD 360, featuring in-field registration and what it delivers in terms of functionality, benefits, and more. 

What is in-field registration?

Point cloud registration, also known as the alignment of two point sets, represents an essential procedure in laser scanning. In the context of in-field registration, this alignment occurs during the scanning process itself, while one is present on-site. During a laser scanning project, it is often imperative to capture multiple scans from diverse positions or perspectives to encompass the entire area of interest comprehensively. In-field registration encompasses the immediate alignment and integration of these distinct scans into a cohesive point cloud, obviating the requirement to transport the data back to the office for registration.

How has registration changed in the latest release of Cyclone FIELD 360?

In earlier versions of the software, there existed a limitation in the registration stage that restricted the quantity of links that could be established to form a bundle. As a result, users were constrained to creating the minimum number of links, resulting in a bundle structure with a linear configuration.

In our latest release of Cyclone FIELD 360, a new feature has been introduced that allows the creation of links to form closed loops to optimise the bundle. This enhancement eliminates the previous restriction on how setups could be connected. Furthermore, after the creation of these links, it is now possible to optimise the bundle by computing the average link error and evenly distributing it across the entire bundle. 

The registration process is performed on the Lightweight Preview Object (LWPO) rather than the complete dataset. The LWPO technology allows for a visual representation of the scan data using only a subset of the actual scanned points. This results in a reduction in data size and minimises the data transfer time between the laser scanner and the mobile device. This reduction in data size and transfer time is crucial for enabling resource-intensive operations, such as automatic point cloud alignment, to be executed efficiently on mobile consumer devices like smartphones or tablets. Even though the registration is computed on the LWPO instead of the full dataset, the quality of the registration remains unaffected. The resulting bundle can be exported and seamlessly used in the desired office software without requiring any additional processing steps.

What are the benefits for our customers?

The in-field registration brings several benefits, enabling customers to complete projects entirely on-site. This entails capturing, registering, and delivering entire projects using a mobile device such as a phone or tablet, eliminating the need for additional processing steps in the office. Conducting registration in the field provides immediate feedback on data quality, ensuring that all essential areas are adequately captured before leaving the site. It also enables on-site verification and validation, minimising the need for expensive rework or revisits to the field. This in-field workflow is a transformative solution for both new and experienced users, enabling the efficient delivery of projects or effective communication with collaborators before leaving the field.

Can you walk me through the registration process?

During the registration process, the user can select from three different options:

1. QuickLink

Upon completion of a second scan within the same job, the QuickLink option will become available. Once selected, the system calculates a link between the preceding setup and the subsequently scanned setup. This process involves the alignment of the two point clouds, utilising information obtained from the Visual Inertial System (VIS) embedded in the scanner. The VIS technology, currently featured in the Leica RTC360 and the newly introduced Leica BLK360, incorporates a set of cameras that track the surrounding features. After alignment, a sequence of Iterative Closest Point (ICP) iterations is performed to accurately match the corresponding points on each point cloud. This entire process is completed within a matter of seconds, requiring the press of just a single button.

2. Pre-align

This becomes available when the user manually initiates the linking process and selects the two setups they wish to link. Once the second setup is chosen, the snackbar presents the Pre-align option, which can be toggled on or off. Enabling Pre-align prompts Cyclone FIELD 360 to analyse the relative positioning of the two point clouds by extracting and fitting together 3D features. Pre-align is particularly beneficial for customers utilizing scanners that lack Visual Inertial System (VIS), such as the Leica P-Series and Leica BLK360 G1 or when scanning in the same job over multiple days. 

3. Optimise

After Pre-align is completed, the next and final step is to optimise the link. This involves executing multiple iterations of the Iterative Closest Point (ICP) algorithm to enhance the alignment quality. By performing these iterations, the system further refines the link between the two point clouds. Like the previous steps, the optimisation process is swift and completed within a matter of seconds.

What other new features are a part of the latest release of Cyclone FIELD 360?

The introduction of registration in Cyclone FIELD 360 4.1 brings about notable enhancements in the linking and alignment views.

Upon pressing the 'Create Link' button, the linking view is displayed which provides a comprehensive display of the entire bundle. The level of detail presented in this view has been significantly improved, allowing for the visibility of all points contained within the Lightweight Preview Object (LWPO). It is important to note that this increased level of detail may pose performance challenges for certain mobile devices with limited processing power. To address this, users are granted the flexibility to choose a low, medium, or high level of detail for the linking view through the software settings.

Furthermore, the updated linking view now incorporates a slicer functionality that enables vertical slicing through the point cloud allowing users to obtain cross-sectional insights and analyse specific sections of the point cloud.

Similar enhancements have been incorporated into the alignment view, which becomes visible following the Pre-align step and exclusively presents the two setups being linked. Within the alignment view, the complete level of detail from the Lightweight Preview Object (LWPO) is consistently displayed to facilitate the registration process. Users are granted the flexibility to toggle between different viewing options.

The first option is a top-down view, providing a comprehensive overview of the point cloud. The second option offers a 3D view where a slicer dynamically traverses the point cloud vertically, allowing for in-depth examination of specific sections. Lastly, a side view is available, presenting a slice direction that traverses across the point cloud, enabling users to gain additional perspectives.

What can we expect in the future from Cyclone FIELD 360?

In the forthcoming updates of Cyclone FIELD 360, notable advancements in the in-field registration are anticipated. These improvements will focus on delivering better feedback regarding the accuracy of links and bundles, along with enhanced user guidance to facilitate optimal outcomes. Users can look forward to a more comprehensive set of tools and features that will assist them in achieving the highest level of results in their registration processes. 

Download Cyclone FIELD 360 from the AppStore and Google Play to get started today, or contact us for more information about our laser scanning solutions. 

Simona Hriscu
Senior Product Engineer, Terrestrial Laser Scanning
Reality Capture Division