Angel Soriano

Multi Sensor Fusion Framework for Indoor-Outdoor Localization of Limited Resource Mobile Robots

This paper presents a sensor fusion framework that improves the localization of mobile robots with limited computational resources. It employs an event based Kalman Filter to combine the measurements of a global sensor and an inertial measurement unit (IMU) on an event based schedule, using fewer resources (execution time and bandwidth) but with similar performance when compared to the traditional methods. The event is defined to reflect the necessity of the global information, when the estimation error covariance exceeds a predefined limit. The proposed experimental platforms are based on the LEGO Mindstorm NXT, and consist of a differential wheel mobile robot navigating indoors with a zenithal camera as global sensor, and an Ackermann steering mobile robot navigating outdoors with a SBG Systems GPS accessed through an IGEP board that also serves as datalogger. The IMU in both robots is built using the NXT motor encoders along with one gyroscope, one compass and two accelerometers from Hitecnic, placed according to a particle based dynamic model of the robots. The tests performed reflect the correct performance and low execution time of the proposed framework. The robustness and stability is observed during a long walk test in both indoors and outdoors environments.

Event-Based Localization in Ackermann Steering Limited Resource Mobile Robots

This paper presents a local sensor fusion technique with an event-based global position correction to improve the localization of a mobile robot with limited computational resources. The proposed algorithms use a modified Kalman filter and a new local dynamic model of an Ackermann steering mobile robot. It has a similar performance but faster execution when compared to more complex fusion schemes, allowing its implementation inside the robot. As a global sensor, an event-based position correction is implemented using the Kalman filter error covariance and the position measurement obtained from a zenithal camera. The solution is tested during a long walk with different trajectories using a LEGO Mindstorm NXT robot.

Multi-Agent Systems Platform for Mobile Robots Collision Avoidance

This paper presents a multi-agent platform to simulate a new methodical approach to the problem of collision avoidance of mobile robots, taking advantages of multi-agents systems to deliver solutions that benefit the whole system. The proposed method has the next phases: collision detection, obstacle identification, negotiation and collision avoidance. In addition of simulations with virtual robots, in order to validate the proposed algorithm, an implementation with real mobile robots has been developed.

Collision Avoidance of Mobile Robots Using Multi-Agent Systems

This paper presents a new methodical approach to the problem of collision avoidance of mobile robots taking advantages of multi-agents systems to deliver solutions that benefit the whole system. The proposed method has the next phases: collision detection, obstacle identification, negotiation and collision avoidance. In addition of simulations with virtual robots, in order to validate the proposed algorithm, an implementation with real mobile robots has been developed. The robots are based on Lego NXT, and they are equipped with a ring of proximity sensors for the collisions detections. The platform for the implementation and management of the multi-agent system is JADE.

Application and Evaluation of Lego NXT Tool for Mobile Robot Control

Abstract Mobile robot control education is a motivating subject due to the practical work that it involves. For this reason it is very important the platform chosen for the laboratory activities with the students. This work will present different activities based on Lego NXT developed for teaching Control Engineering. The Lego tools have been used for the last 5 years for the practical works of “Mecatronica”, a course of the last year of Computer Science Faculty of the Universidad Politecnica de Valencia (Spain). The tasks that the students must do during this course deal with system identification, dynamic control of the robots wheels, kinematic control of the mobile robot, path generation etc. At the end of the Mecatronica course, the students must fill an opinion poll about the work of the course, the tools used, etc. The paper will also describe the students opinions, and they will verify that the Lego NXT is a very interesting and motivating tool. In addition, it is a very good platform for promoting the team work due to its multidisciplinary nature

GEMA 2

Abstract This paper presents a new algorithm for fast mobile robot self-localization in structured indoor environments based on geometrical and analytical matching, GEMA 2 . The proposed method takes advantage of the available structural information to perform a geometrical matching with the environment information provided by measurements collected by a laser range finder. In contrast to other global self-localization algorithms like Monte Carlo or SLAM, GEMA 2 provides a linear cost with respect the number of measures collected, making it suitable for resource-constrained embedded systems. The proposed approach has been implemented and tested in a mobile robot with limited computational resources showing a fast converge from global self-localization.

Implementation of dynamic controllers using real-time middleware for a low-cost parallel robot

As it is well known, robots are complex devices capable of performing very fast and precise movements. Developing robots and their controllers is a very challenge task due to the different technologies that are needed to be dealt with (access to peripherals, real-time operating systems, communications ...) and the amounts of programming work that is needed. Moreover, this work needs to be repeated in most cases when a new robot is developed. A new way is needed for developing the code implemented for controlling these robots that allows to reuse it in a safe way. In this paper, the Orocos (Open Robot Control Software) middleware has been chosen for the controller development. Orocos is a real-time middleware, focused on control systems, especially those related to robotics and automation. Its greatest advantage over the other solutions available is the capability to provide an off-the-shelf hard real-time operation. This is essential in most of the robotics applications, making this middleware in a very suitable piece of software. Since Orocos is a component-based middleware, several CBSD (component-based software development) techniques have been used to design and implement the control system. Thus, using a modular control structure, a number of advantages can be achieved such as code reusability, execution of the modules in a distributed way, ability to load or instantiate a module several times, easy following of flow execution and fewer programming errors. In addition, these components are configurable and reconfigurable in runtime.