Robot-aided Hyperspectral Imaging For Mineral Exploration in Underground Mining Environments

New mining and exploration projects have revived across Europe with an increasing demand for critical raw materials driven by the energy transition and unstable political conditions. Hyperspectral imaging proves to be an excellent tool for quick and efficient non-invasive mineral exploration. By mounting hyperspectral- and LiDAR sensors on...

Identifying high Alpine geomorphological processes using permanent laser scanning time series

Global climate change affects mountain regions such as the European Alps. Consequently, glacier extents decrease, and proglacial areas, the areas that recently lost their ice cover, increase in size. These proglacial areas are subject to a high frequency and magnitude of geomorphological activity and act as a sediment source for downstream...

Realistic correction of sky-coloured points in Mobile Laser Scanning point clouds

The enrichment of the point clouds with colour images improves the visualisation of the data as well as the segmentation and recognition processes. Coloured point clouds are becoming increasingly common, however, the colour they display is not always as expected. Errors in the colouring of point clouds acquired with Mobile Laser Scanning are...

Point-based morphological opening with input data retrieval

Mathematical morphology is a technique recently applied directly for point cloud data. Its working principle is based on the removal and addition of points from an auxiliary point cloud that acts as a structuring element. However, in certain applications within a more complex process, these changes to the original data represent an...

Mathematical morphology directly applied to point cloud data

Many of the point cloud processing techniques have their origin in image processing. But mathematical morphology, despite being one of the most used image processing techniques, has not yet been clearly adapted to point clouds. The aim of this work is to design the basic operations of mathematical morphology applicable to 3D point cloud data,...

CMOS SPAD Sensors for 3D Time-of-Flight Imaging, LiDAR and Ultra-High Speed Cameras

In conventional applications, such as bio-imaging and microscopy, SPAD is typically used as a single-photon counter. However, this advantage has been challenged by other photon-counting technologies, especially from CMOS-based QIS. Comparatively, apart from single-photon counting capability, QIS is superior to SPAD in terms of intrinsic multi...

A CMOS SPAD Imager with Collision Detection and 128 Dynamically Reallocating TDCs for Single-Photon Counting and 3D Time-of-Flight Imaging

Per-pixel time-to-digital converter (TDC) architectures have been exploited by single-photon avalanche diode (SPAD) sensors to achieve high photon throughput, but at the expense of fill factor, pixel pitch and readout efficiency. In contrast, TDC sharing architecture usually features high fill factor at small pixel pitch and energy efficient...