Jaime Gómez-García-Bermejo

Road Crack Detection Using Visual Features Extracted by Gabor Filters

Data has been acquired and used to train and test pavement management systems (PMS) and methods. The article discusses how PMS require detailed information on the current state of the roads in order to take appropriate actions to optimize expenditures on maintenance and rehabilitation. The presence of cracks is a crucial aspect to be considered. A solution based on an instrumented vehicle that is equipped with an imaging system, two Inertial Profilers, a Differential Global Positioning System (DGPS), and a webcam is presented. Information about the state of the road is acquired at normal road speed. A method that is based on the use of Gabor filters is used to detect longitudinal and transverse cracks. The methodologies used to create Gabor filter banks and the use of the filtered images as descriptors for subsequent classifiers are discussed in detail in the article. The article also evaluates three different methodologies for setting the threshold of the classifiers. Finally, an AdaBoost algorithm is used for selecting and combining the classifiers, which improves the results provided by a single classifier. The article discusses how suitable results have been obtained in comparison with other reference works.

An Effective Texture Mapping Approach for 3D Models Obtained from Laser Scanner Data to Building Documentation

: Obtaining virtual models from real buildings, terrains, or building works is a matter of increased interest in construction. The application of such models ranges from technical use in architecture and civil engineering, to multimedia presentation, or remote visits through the web. This is becoming possible thanks to recent advances in laser scanning technology and related 3D processing algorithms. Moreover, real texture mapped onto 3D models is often required for communication, cataloguing, or digital documentation projects. In this article, an effective methodology to obtain digital building documentation based on 3D textured models is presented. First of all, a brief presentation of laser scanners is given as their data are used. An approach for mapping photographic images onto 3D models is also presented. The proposed approach, based on a camera registration method, offers high flexibility as it is based on hand-held cameras and can be implemented in a computing-effective way. A method for automatic image selection in overlapped areas is also presented. Finally, some hints are given concerning the automatic extraction of sections, orthophotos, and feature lines from the models. Experimental results focused on heritage buildings are shown, which demonstrate the suitability of the proposed techniques.

A realistic, virtual head for human-computer interaction

In this paper an interactive and realistic virtual head oriented to human-computer interaction and social robotics is presented. It has been designed following a hybrid approach, taking robotic characteristics into account and searching for a convergence between these characteristics, real facial actions and animation techniques. An initial head model is first obtained from a real person using a laser scanner. Then the model is animated using a hierarchical skeleton based procedure. The proposed rig structure is close to real facial muscular anatomy and its behaviour follows the Facial Action Coding System. Speech synthesis and visual human-face tracking capabilities are also integrated for providing the head with further interaction ability. Using the said hybrid approach, the head can be readily linked to a social-robot architecture. The opinions of a number of persons interacting with this social avatar have been evaluated and are reported in the paper, as against their reactions when interacting with a social robot with a mechatronic face. Results show the suitability of the avatar for on-screen, real-time interfacing in human-computer interaction. The proposed technique could also be helpful in the future for designing and parameterizing mechatronic human-like heads for social robots.

Nonverbal communication with a multimodal agent via facial expression recognition

Based on our previous work in the development of a multimodal animated avatar oriented to human-machine interaction and social robotics, a facial expression recognition system is presented in this paper. Both the avatars architecture and facial recognition system have been oriented to FACS Action Units recognition and generation, so they can be easily integrated. The resulting animated system is able to maintain nonverbal and verbal bidirectional communication, enhancing the interaction with the avatar and making it more natural for the users.

Automated Visual Inspection of Road Surface Cracks

Pavement maintenance requires knowing the state of the road surface. Human inspection is the most common method for evaluating this state. Recently, the automated visual inspection has been addressed, but some important questions remain open concerning the variable ambient lighting, shadows, device synchronisation and the large amount of data. In the present paper, an automated visual inspection system is presented. Images are obtained using laser lighting and linear cameras onboard a vehicle. Longitudinal and transversal cracks are detected and classified using a novel approach based on combining traditional features and Gabor filters. A Differential Global Positioning System (DGPS), a web camera and an Inertial Profiler to measure the International Roughness Index (IRI) are also considered in order to obtain comprehensive information about the road state. Implementation details are given concerning image acquisition and processing, system architecture and data synchronisation. Field results are presented which prove the suitability of the approach.

Enhanced automatic detection of road surface cracks by combining 2D/3D image processing techniques

In this paper, a comprehensive automatic visual inspection system for detecting pavement cracks, built around a Laser Road Inspection System (LRIS) onboard an instrumented vehicle, is presented. Two inertial profilers, a Differential Global Position System (DGPS), a high-definition camera and a high-speed area scan camera are the additional acquisition equipment. Visual appearance and geometrical information are obtained simultaneously since 3D profiles are obtained by capturing the laser line projected by the LRIS with the external area scan camera. Using AdaBoost algorithm for the combination of the processing results of these two types of data allows us to improve surface crack detection rates.

Long-term assessment of a service robot in a hotel environment

The long term evaluation of the Sacarino robot is presented in this paper. The study is aimed to improve the robots capabilities as a bellboy in a hotel; walking alongside the guests, providing information about the city and the hotel and providing hotel-related services. The paper establishes a three-stage assessment methodology based on the continuous measurement of a set of metrics regarding navigation and interaction with guests. Sacarino has been automatically collecting information in a real hotel environment for long periods of time. The acquired information has been analyzed and used to improve the robots operation in the hotel through successive refinements. Some interesting considerations and useful hints for the researchers of service robots have been extracted from the analysis of the results. Long-term evaluation in real environment under unsupervised conditions.The evaluation methodology includes both qualitative and quantitative aspects.A set of metrics are analyzed concerning social interaction and navigation.Improvement of the robots performance through assessment feedback.

Low cost indoor mobile robot localization system

In this paper a low cost mobile robot localization system that uses the popular Wii remote control (WiiMote) is presented. Both, the WiiMote and a specialized IR light source are located on top of the robot pointing upwards. The IR light is reflected on retroreflective tags located on the ceiling of the robot working area. Two solutions that depend on the working environment, amount of tags needed and robot characteristics are presented. The first solution is deterministic and more restrictive in the quality of sensor data and number of tags. The second solution is a stochastic solution that integrates dead-reckoning information and IR tag readings using a particle filter. The cost of the onboard localization device, including the WiiMote is less than

Reconstruction of Three Dimensional Models of Environments with a Mobile Robot

50 while each tag costs less than

Applying Deep Learning Techniques to Cultural Heritage Images Within the INCEPTION Project

0.05. The system has been tested on a real mobile robot system used for security and surveillance tasks.