This article describes an electric vehicle equipped with a laser scanner and a highly accurate absolute positioning system aimed at surveying the geometry of roads. The main advantages of the proposed system with respect to conventional topographic procedures are the possibility of achieving a much higher density of surveyed points and its efficiency while keeping almost the same accuracy-a standard deviation of 12 mm of absolute error. The data acquisition process is managed by an on-board computer which, in a synchronized way, deals with laser scanning and readings from three realtime-kinematics-enabled millimeter GPS receivers. The three-dimensional position and orientation of the vehicle (6 degrees of freedom) all along its trajectory is calculated off-line by a custom software and, with that information, the system also obtains the absolute coordinates of the road scanned points. This article also presents a rigorous description regarding the theory behind 3D reconstruction and the calibration process.

A parabolic trough collector has been developed for various applications in the 200–400°C temperature range in solar fields up to the hundreds Megawatts range. The design of a new support structure of the collector included concept studies, wind tunnel measurements, finite elements method (FEM) analyses and resulted in a structure with a central framework element. This torque box design will have lower weight and less deformation of the collector structure than the other designs considered. Therefore it will be possible in future to connect more collector elements on one drive which results in reduced total number of drives and interconnecting pipes, thus reducing the installation cost and thermal losses. In terms of the degree of material usage further weight reduction will be possible. The presented design has a significant potential for cost reduction, the most important goal of the EuroTrough project. The prototype has been set-up and is under testing at PSA (Plataforma Solar de Almería) for its thermal and mechanical properties.

The main objective of the system presented in this paper is to provide surveyors and engineers with a new photogrammetry device that can be easily integrated with surveying total stations and a global navigation satellite system (GNSS) infrastructure at a construction site, taking advantage of their accuracy and overcoming limitations of aerial vehicles with respect to weight, autonomy and skilled operator requirements in aerial photogrammetry. The system moves between two mounting points, in a blondin ropeway configuration, at the construction site, taking pictures and recording the data of the position and the orientation along the cable path. A cascaded extended Kalman filter is used to integrate measurements from the on-board inertial measurement unit (IMU), a GPS and a GNSS. Experimental results taken in a construction site show the system performance, including the validation of the position estimation, with a robotic surveying total station, or the creation of a digital surface model (DSM), using the emergent structure from motion (SfM) techniques and open software. The georeferencing of the DSM is performed based on estimated camera position or using ground control points (GCPs).

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