A compact two-dimensional micro scanner with small volume, large deflection angles and high frequency is presented and the two-dimensional laser scanning is achieved by specular reflection. To achieve large deflection angles, the micro scanner excited by a piezoelectric actuator operates in the resonance mode. The scanning frequencies and the maximum scanning angles of the two degrees of freedo...

Many image guided surgical (IGS) procedures use surface representations of anatomical features to provide a registration between physical space and image space. While anatomical fiducial registration techniques can often be compromised by soft tissue deformation, laser-scanning systems offer a non-contact method for accurately resolving geometric surfaces. This digitization approach is particul...

Accurate modelling of individual trees is essential for forestry applications e.g. forestry inventory and biomass estimation. This paper aims to utilise Terrestrial Laser Scanners (TLS) in order to derive a three dimensional (3D) tree structure and compute its volume. A new approach is proposed and tested to estimate the tree structure and leaf area using precise voxel-based tree models. In thi...

The surface layer of road pavement has a particular importance in relation to the satisfaction of the primary demands of locomotion, such as security and eco-compatibility. Among those pavement surface characteristics, the "texture" appears to be one of the most interesting with regard to the attainment of skid resistance. Specifications and regulations, providing a wide range of functional ind...

Chen, Yi-Ting Ph.D., Purdue University, May 2015. Laser Scanner Jitter Characterization, Page Content Analysis for Optimal Rendering, and Understanding Image Graininess. Major Professor: Jan P. Allebach. In Chapter 1, the electrophotographic (EP) process is widely used in imaging systems such as laser printers and office copiers. In the EP process, laser scanner jitter is a common artifact that...

Dimensional control based on 3D laser scanning techniques is widely used in practice. We describe the application of a hybrid 3D-2D laser scanning system to the characterization of slate slabs with structural defects that are difficult for the human eye to characterize objectively. Our study is based on automating the process using a 3D laser scanner and a 2D camera. Our results demonstrate tha...

Airborne laser altimetry is a highly efficient and accurate method of obtaining data for the determination of visible surface topography. With minimal processing, the laser data can provide coordinates of points on the visible surface with high spatial frequency and precision. Although this technology has benefits compared to photogrammetric techniques, there are limiting factors due to the las...

A method based on extracted trunks is proposed for automatic determination of corresponding trees between a georeferenced pair of terrestrial images and airborne laser scanner data in a wooded area. Trunks in the terrestrial images are obtained by region growing segmentation between left and right edges of trunks detected within a region of interest. Trunks in a digital tree height model genera...

Laser scanning technology is one of the most integral parts of today's scientific research, manufacturing, defense, and biomedicine. In many applications, high-speed scanning capability is essential for scanning a large area in a short time and multi-dimensional sensing of moving objects and dynamical processes with fine temporal resolution. Unfortunately, conventional laser scanners are often ...