Evaluation of the Apple iPhone 12 Pro LiDAR for an Application in Geosciences

Abstract

Traditionally, topographic surveying in earth sciences requires high financial investments, elaborate logistics, complicated training of staff and extensive data processing. Recently, off-the-shelf drones with optical sensors already reduced the costs for obtaining a high-resolution dataset of an Earth surface considerably. Nevertheless, costs and complexity associated with topographic surveying are still high. In 2020, Apple Inc. released the iPad Pro 2020 and the iPhone 12 Pro with novel build-in LiDAR sensors. Here we investigate the basic technical capabilities of the LiDAR sensors and we test the application at a coastal cliff in Denmark. The results are compared to state-of-the-art Structure from Motion Multi-View Stereo (SfM MVS) point clouds. The LiDAR sensors create accurate high-resolution models of small objects with a side length > 10 cm with an absolute accuracy of ± 1 cm. 3D models with the dimensions of up to 130 × 15 × 10 m of a coastal cliff with an absolute accuracy of ± 10 cm are compiled. Overall, the versatility in handling outweighs the range limitations, making the Apple LiDAR devices cost-effective alternatives to established techniques in remote sensing with possible fields of application for a wide range of geo-scientific areas and teaching.

Measuring crater volumes from bullet impacts: implications for field methods and cratering mechanics

“…Imaging of a site for photogrammetry models can be done relatively quickly (minutes per impact), but the post-field production and analysis of models (hours to tens of hours) lengthens the overall method time. Smartphones cameras, and the Light Detection and Ranging (LiDAR) capability of new generation iPhones or hand-held scanners, are increasingly able to generate 3D SfM models approaching the precision of those using digital cameras and SfM software, or those derived from terrestrial laser scanning (TLS) 36,37 . The LiDAR sensors in iPhones were developed to enhance photographs, and not to produce surface coordinates like traditional TLS.…”

Smartphone LiDAR Technologies for Surveying and Reality Modelling in Urban Scenarios: Evaluation Methods, Performance and Challenges

“…The pulse time of flight (dToF) is measured by a Single Photon Avalanche Photodiode (SPAD). The combination of VCEL and SPAD has made the implementation of flash-LiDAR solutions in smartphones possible [2].…”

“…The sensors were originally used to improve the quality of photos (e.g., improved camera focus, bokeh effect, etc.) and to enable augmented reality applications, but they proved to be suitable for scientific purposes [1][2][3].…”

Evaluation of low-cost Raspberry Pi sensors for photogrammetry of glacier calving fronts

“…Images from the Raspberry Pi were georeferenced by aligning them to images captured by the UAV and producing a sparse point cloud, before removing UAV images to produce the final dense point clouds. Point clouds from both sensors were therefore referenced to this RTK system only, rather than having a global reference (akin to Luetzenburg et al, 2021). While the Raspberry Pi images could be successfully aligned without UAV images, our workflow was designed to unify the coordinate systems of the point clouds and thereby avoid confounding co-registration errors in the cloud comparison.…”

“…Over glacier calving margins, placing ground control points is especially challenging and alternate methods are required (Mallalieu et al, 2017). There is precedent in using the geospatial data from one point cloud to reference another when comparing sensors (Zhang et al, 2019;Luetzenburg et al, 2021). Alternatively, the positions of the cameras can be used to determine the georeferencing.…”