José Ramiro Martínez-de Dios

Automatic Forest-Fire Measuring Using Ground Stations and Unmanned Aerial Systems

This paper presents a novel system for automatic forest-fire measurement using cameras distributed at ground stations and mounted on Unmanned Aerial Systems (UAS). It can obtain geometrical measurements of forest fires in real-time such as the location and shape of the fire front, flame height and rate of spread, among others. Measurement of forest fires is a challenging problem that is affected by numerous potential sources of error. The proposed system addresses them by exploiting the complementarities between infrared and visual cameras located at different ground locations together with others onboard Unmanned Aerial Systems (UAS). The system applies image processing and geo-location techniques to obtain forest-fire measurements individually from each camera and then integrates the results from all the cameras using statistical data fusion techniques. The proposed system has been extensively tested and validated in close-to-operational conditions in field fire experiments with controlled safety conditions carried out in Portugal and Spain from 2001 to 2006.

An integrated testbed for cooperative perception with heterogeneous mobile and static sensors.

Cooperation among devices with different sensing, computing and communication capabilities provides interesting possibilities in a growing number of problems and applications including domotics (domestic robotics), environmental monitoring or intelligent cities, among others. Despite the increasing interest in academic and industrial communities, experimental tools for evaluation and comparison of cooperative algorithms for such heterogeneous technologies are still very scarce. This paper presents a remote testbed with mobile robots and Wireless Sensor Networks (WSN) equipped with a set of low-cost off-the-shelf sensors, commonly used in cooperative perception research and applications, that present high degree of heterogeneity in their technology, sensed magnitudes, features, output bandwidth, interfaces and power consumption, among others. Its open and modular architecture allows tight integration and interoperability between mobile robots and WSN through a bidirectional protocol that enables full interaction. Moreover, the integration of standard tools and interfaces increases usability, allowing an easy extension to new hardware and software components and the reuse of code. Different levels of decentralization are considered, supporting from totally distributed to centralized approaches. Developed for the EU-funded Cooperating Objects Network of Excellence (CONET) and currently available at the School of Engineering of Seville (Spain), the testbed provides full remote control through the Internet. Numerous experiments have been performed, some of which are described in the paper.

A WSN-Based Tool for Urban and Industrial Fire-Fighting

This paper describes a WSN tool to increase safety in urban and industrial fire-fighting activities. Unlike most approaches, we assume that there is no preexisting WSN in the building, which involves interesting advantages but imposes some constraints. The system integrates the following functionalities: fire monitoring, firefighter monitoring and dynamic escape path guiding. It also includes a robust localization method that employs RSSI-range models dynamically trained to cope with the peculiarities of the environment. The training and application stages of the method are applied simultaneously, resulting in significant adaptability. Besides simulations and laboratory tests, a prototype of the proposed system has been validated in close-to-operational conditions.This paper describes a WSN tool to increase safety in urban and industrial fire-fighting activities. Unlike most approaches, we assume that there is no preexisting WSN in the building, which involves interesting advantages but imposes some constraints. The system integrates the following functionalities: fire monitoring, firefighter monitoring and dynamic escape path guiding. It also includes a robust localization method that employs RSSI-range models dynamically trained to cope with the peculiarities of the environment. The training and application stages of the method are applied simultaneously, resulting in significant adaptability. Besides simulations and laboratory tests, a prototype of the proposed system has been validated in close-to-operational conditions.

Efficient Cluster-Based Tracking Mechanisms for Camera-Based Wireless Sensor Networks

This paper proposes mechanisms to efficiently address critical tasks in the operation of cluster-based target tracking, namely: (1) measurement integration, (2) inclusion/exclusion in the cluster, and (3) cluster head rotation. They all employ distributed probabilistic tools designed to take into account wireless camera networks (WCNs) capabilities and constraints. They use efficient and distribution-friendly representations and metrics in which each node contributes to the computation in each mechanism without requiring any prior knowledge of the rest of the nodes. These mechanisms are integrated in two different distributed schemes so that they can be implemented in constant time regardless of the cluster size. Their experimental validation showed that the proposed mechanisms and schemes significantly reduce energy consumption (>55 percent) and computational burden with respect to existing methods.

Testbeds for ubiquitous robotics: A survey

The growing interest in ubiquitous robotics has originated in the last years the development of a high variety of testbeds. This paper presents a survey on existing ubiquitous robotics testbeds comprising networked mobile robots and networks of distributed sensors, cameras and smartphones, among others. The survey provides an insight into the testbed design, internal behavior and use, identifying trends and existing gaps and proposing guidelines for testbed developers. The level of interoperability among different ubiquitous robotics technologies is used as the main conducting criterion of the survey. Other features analyzed include testbed architectures, target experiments and usability tools.

On the Cooperation between Mobile Robots and Wireless Sensor Networks

Employing cooperative heterogeneous systems can enrich application scenarios and achieve higher application performance. The combination of mobile robots and Wireless Sensor Networks (WSNs) is a good example of such cooperation, and many recent research results have highlighted the benefits of the marriage of these two technologies. The main objectives of this chapter include: (1) providing a survey on a variety of applications with cooperating mobile robots and WSNs based on the roles they play for interaction, and (2) elaborating different cooperative interactions of robots and WSNs in our ongoing project, PLAtform for the deployment and operation of heterogeneous NETworked cooperating objects (PLANET), which is an integrated framework of heterogeneous cooperative objects for network deployment and operations.

An integrated testbed for heterogeneous mobile robots and other Cooperating Objects

This paper describes a testbed for general experimentation involving Cooperating Objects (COs). Its architecture considers all COs at the same level. It allows a multiple schemes including multi-robot, WSNs experiments and robot-WSN collaboration working as peers. Currently comprised of 6 mobile robots (5 Pioneer 3AT and one outdoor robot) and 40 static WSN nodes equipped with cameras (IEEE1394 for the robots and embedded cameras for the WSN nodes), laser rangers, and other sensors, it can be easily extended with other hardware due to the use of a modular architecture and standard software tools and interfaces. The testbed allows testing centralized and distributed techniques, is suitable for indoors and outdoors and can be accessed through the Internet for online remote monitoring and visualization. The main experiments already carried out, some of which are described in the paper, focused on cooperative perception and robot-WSN collaboration for network repairing.

An Adaptive Scheme for Robot Localization and Mapping with Dynamically Configurable Inter-Beacon Range Measurements

This work is motivated by robot-sensor network cooperation techniques where sensor nodes (beacons) are used as landmarks for range-only (RO) simultaneous localization and mapping (SLAM). This paper presents a RO-SLAM scheme that actuates over the measurement gathering process using mechanisms that dynamically modify the rate and variety of measurements that are integrated in the SLAM filter. It includes a measurement gathering module that can be configured to collect direct robot-beacon and inter-beacon measurements with different inter-beacon depth levels and at different rates. It also includes a supervision module that monitors the SLAM performance and dynamically selects the measurement gathering configuration balancing SLAM accuracy and resource consumption. The proposed scheme has been applied to an extended Kalman filter SLAM with auxiliary particle filters for beacon initialization (PF-EKF SLAM) and validated with experiments performed in the CONET Integrated Testbed. It achieved lower map and robot errors (34% and 14%, respectively) than traditional methods with a lower computational burden (16%) and similar beacon energy consumption.

CONET Integrated Testbed Architecture

The objective of this chapter is to present the architecture of the CONET Integrated Testbed for Cooperating Objects. Interoperability, flexibility and usability were the main requirements in the development of the CONET Integrated Testbed. Its software architecture was developed to enable the interaction of heterogeneous devices with wide differences in sensing, computing and communication capabilities. On the other hand, the testbed was devised to fulfil a generalist approach, i.e. to support a wide range of experiments in as many applications as possible.

Wireless Sensor Network Connectivity and Redundancy Repairing with Mobile Robots

This chapter presents a method for repairing the connectivity and redundancy of a WSN using mobile robots. It comprises three mechanisms: diagnosis, connectivity repairing and redundancy repairing. During the diagnosis stage the robots survey the scenario learning all required information of the problem. The connectivity repairing mechanism, which takes place after the diagnosis stage, finds the best deployment locations to ensure that the WSN has 1-connectivity. The redundancy repairing mechanism finds the locations where the deployment of new nodes best improves fault tolerance to node failures. The proposed scheme does not use any parameters or assumptions since it acquires all the required information during the diagnosis stage. Besides, its solution is very close to the optimal solution –in all the experiments performed it differed in one node maximum– but requires only a fraction of the time required by the optimal method. The proposed method has been evaluated in simulations and has been validated in experiments carried out in the CONET Robot-WSN Integrated Testbed.