An Implemented of a Real-Time Experimental Setup for Robotic Teleoperation System

The development of this work presents the implementation of an experimental platform, which will permit to investigate on a methodology for the design and analysis of a teleoperated system, considering the delay in the communication channel. The project has been developed in partnership with the laboratory of Automatic and Robotics of the Universidad Politécnica de Madrid and the Laboratory at the Centro de Tecnologías Avanzadas de Manufactura at the Pontificia Universidad Católica del Perú. The mechanical structure of the arm that is located in the remote side has been built and the electric servomechanism has been mounted to control their movement. The experimental test of the Teleoperation system has been developed. The PC104 card commands the power interface and sensors of the DC motor of each articulation of the arm. Has developed the drives for the management of the operations of the master and the slave: send/reception of position, speed, acceleration and current data through a CAN network. The programs for the interconnection through a LAN network, between the Windows Operating System and the Real-time Operating System (QNX), has been developed. The utility of the developed platform (hardware and software) has been demonstrated.

Real-time image processing for crop/weed discrimination in maize fields

This paper presents a computer vision system that successfully discriminates between weed patches and crop rows under uncontrolled lighting in real-time. The system consists of two independent subsystems, a fast image processing delivering results in real-time (Fast Image Processing, FIP), and a slower and more accurate processing (Robust Crop Row Detection, RCRD) that is used to correct the first subsystem's mistakes. This combination produces a system that achieves very good results under a wide variety of conditions. Tested on several maize videos taken of different fields and during different years, the system successfully detects an average of 95% of weeds and 80% of crops under different illumination, soil humidity and weed/crop growth conditions. Moreover, the system has been shown to produce acceptable results even under very difficult conditions, such as in the presence of dramatic sowing errors or abrupt camera movements. The computer vision system has been developed for integration into a treatment system because the ideal setup for any weed sprayer system would include a tool that could provide information on the weeds and crops present at each point in real-time, while the tractor mounting the spraying bar is moving

Time and space partitioning the EagleEye reference mission

We discuss experiences gained by porting a Software Validation Facility (SVF) and a satellite Central Software (CSW) to a platform with support for Time and Space Partitioning (TSP). The SVF and CSW are part of the EagleEye Reference mission of the European Space Agency (ESA). As a reference mission, EagleEye is a perfect candidate to evaluate practical aspects of developing satellite CSW for and on TSP platforms. The specific TSP platform we used consists of a simulate D LEON3 CPU controlled by the XtratuM separation micro-kernel. On top of this, we run five separate partitions. Each partition ru n s its own real-time operating system or Ada run-time kernel, which in turn are running the application software of the CSW. We describe issues related to partitioning; inter-partition communication; scheduling; I/O; and fault-detection, isolation, and recovery (FDIR)

Real-time Surveillance Application by Multiple Detectors and Compressive Trackers

A real-time surveillance system for IP network cameras is presented. Motion, part-body, and whole-body detectors are efficiently combined to generate robust and fast detections, which feed multiple compressive trackers. The generated trajectories are then improved using a reidentification strategy for long term operation.

Adapting mode switches into the hierarchical scheduling

Mode switches are used to partition the system’s behavior into different modes to reduce the complexity of large embedded systems. Such systems operate in multiple modes in which each one corresponds to a specific application scenario; these are called Multi-Mode Systems (MMS). A different piece of software is normally executed for each mode. At any given time, the system can be in one of the predefined modes and then be switched to another as a result of a certain condition. A mode switch mechanism (or mode change protocol) is used to shift the system from one mode to another at run-time. In this thesis we have used a hierarchical scheduling framework to implement a multi-mode system called Multi-Mode Hierarchical Scheduling Framework (MMHSF). A two-level Hierarchical Scheduling Framework (HSF) has already been implemented in an open source real-time operating system, FreeRTOS, to support temporal isolation among real-time components. The main contribution of this thesis is the extension of the HSF featuring a multimode feature with an emphasis on making minimal changes in the underlying operating system (FreeRTOS) and its HSF implementation. Our implementation uses fixed-priority preemptive scheduling at both local and global scheduling levels and idling periodic servers. It also now supports different modes of the system which can be switched at run-time. Each subsystem and task exhibit different timing attributes according to mode, and upon a Mode Change Request (MCR) the task-set and timing interfaces of the entire system (including subsystems and tasks) undergo a change. A Mode Change Protocol specifies precisely how the system-mode will be changed. However, an application may not only need to change a mode but also a different mode change protocol semantic. For example, the mode change from normal to shutdown can allow all the tasks to be completed before the mode itself is changed, while changing a mode from normal to emergency may require aborting all tasks instantly. In our work, both the system mode and the mode change protocol can be changed at run-time. We have implemented three different mode change protocols to switch from one mode to another: the Suspend/resume protocol, the Abort protocol, and the Complete protocol. These protocols increase the flexibility of the system, allowing users to select the way they want to switch to a new mode. The implementation of MMHSF is tested and evaluated on an AVR-based 32 bit board EVK1100 with an AVR32UC3A0512 micro-controller. We have tested the behavior of each system mode and for each mode change protocol. We also provide the results for the performance measures of all mode change protocols in the thesis. RESUMEN Los conmutadores de modo son usados para particionar el comportamiento del sistema en diferentes modos, reduciendo así la complejidad de grandes sistemas empotrados. Estos sistemas tienen multiples modos de operación, cada uno de ellos correspondiente a distintos escenarios y para distintas aplicaciones; son llamados Sistemas Multimodales (o en inglés “Multi-Mode Systems” o MMS). Normalmente cada modo ejecuta una parte de código distinto. En un momento dado el sistema, que está en un modo concreto, puede ser cambiado a otro modo distinto como resultado de alguna condicion impuesta previamente. Los mecanismos de cambio de modo (o protocolos de cambio de modo) son usados para mover el sistema de un modo a otro durante el tiempo de ejecución. En este trabajo se ha usado un modelo de sistema operativo para implementar un sistema multimodo llamado MMHSF, siglas en inglés correspondientes a (Multi-Mode Hierarchical Scheduling Framework). Este sistema está basado en el HSF (Hierarchical Scheduling Framework), un modelo de sistema operativo con jerarquía de dos niveles, implementado en un sistema operativo en tiempo real de libre distribución llamado FreeRTOS, capaz de permitir el aislamiento temporal entre componentes. La principal contribución de este trabajo es la ampliación del HSF convirtiendolo en un sistema multimodo realizando los cambios mínimos necesarios sobre el sistema operativo FreeRTOS y la implementación ya existente del HSF. Esta implementación usa un sistema de planificación de prioridad fija para ambos niveles de jerarquía, ocupando el tiempo entre tareas con un “modo reposo”. Además el sistema es capaz de cambiar de un modo a otro en tiempo de ejecución. Cada subsistema y tarea son capaces de tener distintos atributos de tiempo (prioridad, periodo y tiempo de ejecución) en función del modo. Bajo una demanda de cambio de modo (Mode Change Request MCR) se puede variar el set de tareas en ejecución, así como los atributos de los servidores y las tareas. Un protocolo de cambio de modo espeficica precisamente cómo será cambiado el sistema de un modo a otro. Sin embargo una aplicación puede requerir no solo un cambio de modo, sino que lo haga de una forma especifica. Por ejemplo, el cambio de modo de “normal” a “apagado” puede permitir a las tareas en ejecución ser finalizadas antes de que se complete la transición, pero sin embargo el cambio de “normal” a “emergencia” puede requerir abortar todas las tareas instantaneamente. En este trabajo ambas características, tanto el modo como el protocolo de cambio, pueden ser cambiadas en tiempo de ejecución, pero deben ser previamente definidas por el desarrollador. Han sido definidos tres protocolos de cambios: el protocolo “suspender/continuar”, protocolo “abortar” y el protocolo “completar”. Estos protocolos incrementan la flexibilidad del sistema, permitiendo al usuario seleccionar de que forma quieren cambiar hacia el nuevo modo. La implementación del MMHSF ha sido testada y evaluada en una placa AVR EVK1100, con un micro-controlador AVR32UC3A0. Se ha comprobado el comportamiento de los distintos modos para los distintos protocolos, definidos previamente. Como resultado se proporcionan las medidades de rendimiento de los distintos protocolos de cambio de modo.

Prototipado de sistemas multiprocesador en FPGA

Los procesadores tradicionales de un solo núcleo han tenido que enfrentarse a grandes desafíos para poder mejorar su rendimiento y eficiencia energética. Mientras tanto, el rápido avance de las tecnologías de fabricación ha permitido la implementación de varios procesadores en un solo chip, ofreciendo un alto rendimiento y eficiencia energética. Éstos son los llamados procesadores multinúcleo. El objetivo de este proyecto es realizar un sistema multiprocesador para el procesamiento digital de señales de radio. Este sistema multiprocesador puede ser implementado en una tarjeta de prototipado. Para ello se ha utilizado el softcore MB-Lite y el sistema operativo en tiempo real FreeRTOS. ABSTRACT. Traditional single-core processors have faced great challenges to improve their performance and energy efficiency. Meanwhile, rapid advancing fabrication technologies have enabled the implementation of several processors in a single chip, providing high performance and energy efficiency. These are called multi-core processors. The aim of this project is to perform a multiprocessor system for digital radio signal processing. This multiprocessor system can be implemented in a general purpose prototyping card using. To achieve this project, the MB-Lite softcore and the FreeRTOS real time operating system have been used.

Adaptive Multi-Camera System for Real Time Object Detection

In this paper we present an adaptive multi-camera system for real time object detection able to efficiently adjust the computational requirements of video processing blocks to the available processing power and the activity of the scene. The system is based on a two level adaptation strategy that works at local and at global level. Object detection is based on a Gaussian mixtures model background subtraction algorithm. Results show that the system can efficiently adapt the algorithm parameters without a significant loss in the detection accuracy.

Automatic generation of real-time deformable parametric model of the aorta for a VR-based catheterism guidance system

The purpose of this work is twofold: first, to develop a process to automatically create parametric models of the aorta that can adapt to any possible intraoperative deformation of the vessel. Second, it intends to provide the tools needed to perform this deformation in real time, by means of a non-rigid registration method. This dynamically deformable model will later be used in a VR-based surgery guidance system for aortic catheterism procedures, showing the vessel changes in real time.

Distributed Web Interface for Real-Time Spatial Audio Reproduction System

SSR es el acrónimo de SoundScape Renderer (tool for real-time spatial audio reproduction providing a variety of rendering algorithms), es un programa escrito en su mayoría en C++. El programa permite al usuario escuchar tanto sonidos grabados con anterioridad como sonidos en directo. El sonido o los sonidos se oirán, desde el punto de vista del oyente, como si el sonido se produjese en el punto que el programa decida, lo interesante de este proyecto es que el sonido podrá cambiar de lugar, moverse, etc. Todo en tiempo real. Esto se consigue sin modificar el sonido al grabarlo pero sí al emitirlo, el programa calcula las variaciones necesarias para que al emitir el sonido al oyente le llegue como si el sonido realmente se generase en un punto del espacio o lo más parecido posible. La sensación de movimiento no deja de ser el punto anterior cambiando de lugar. La idea era crear una aplicación web basada en Canvas de HTML5 que se comunicará con esta interfaz de usuario remota. Así se solucionarían todos los problemas de compatibilidad ya que cualquier dispositivo con posibilidad de visualizar páginas web podría correr una aplicación basada en estándares web, por ejemplo un sistema con Windows o un móvil con navegador. El protocolo debía de ser WebSocket porque es un protocolo HTML5 y ofrece las “garantías” de latencia que una aplicación con necesidades de información en tiempo real requiere. Nos permite una comunicación full-dúplex asíncrona sin mucho payload que es justo lo que se venía a evitar al no usar polling normal de HTML. El problema que surgió fue que la interfaz de usuario de red que tenía el programa no era compatible con WebSocket debido a un handshacking inicial y obligatorio que realiza el protocolo, por lo que se necesitaba otra interfaz de red. Se decidió entonces cambiar a JSON como formato para el intercambio de mensajes. Al final el proyecto comprende no sólo la aplicación web basada en Canvas sino también un servidor funcional y la definición de una nueva interfaz de usuario de red con su protocolo añadido. ABSTRACT. This project aims to become a part of the SSR tool to extend its capabilities in the field of the access. SSR is an acronym for SoundScape Renderer, is a program mostly written in C++ that allows you to hear already recorded or live sound with a variety of sound equipment as if the sound came from a desired place in the space. Like the web-page of the SSR says surely better explained: “The SoundScape Renderer (SSR) is a tool for real-time spatial audio reproduction providing a variety of rendering algorithms.” The application can be used with a graphical interface written in Qt but has also a network interface for external applications to use it. This network interface communicates using XML messages. A good example of it is the Android client. This Android client is already working. In order to use the application should be run it by loading an audio source and the wanted environment so that the renderer knows what to do. In that moment the server binds and anyone can use the network interface. Since the network interface is documented everyone can make an application to interact with this network interface. So the application can have as many user interfaces as wanted. The part that is developed in this project has nothing to do neither with audio rendering nor even with the reproduction of the spatial audio. The part that is developed here is about the interface used in the SSR application. As it can be deduced from the title: “Distributed Web Interface for Real-Time Spatial Audio Reproduction System”, this work aims only to offer the interface via web for the SSR (“Real-Time Spatial Audio Reproduction System”). The idea is not to make a new graphical interface for SSR but to allow more types of interfaces and communication. To accomplish the objective of allowing more graphical interfaces this project is going to use a new network interface. By now the SSR application is using only XML for data interchange but this new network interface support JSON. This project comprehends the server that launch the application, the user interface and the new network interface. It is done with these modules in order to allow creating new user interfaces that can communicate with the server or new servers that can communicate with the user interface by defining a complete network interface for data interchange.

A Propose-and-revise System for Real-time Traffic Management

The aim of this paper is to describe an intelligent system for the problem of real time road traffic control. The purpose of the system is to help traffic engineers in the selection of the state of traffic control devices on real time, using data recorded by traffic detectors on motorways. The system follows an advanced knowledge-based approach that implements an abstract generic problem solving method, called propose-and-revise, which was proposed in Artificial Intelligence, within the knowledge engineering field, as a standard cognitive structure oriented to solve configuration design problems. The paper presents the knowledge model of such a system together with the strategy of inference and describes how it was applied for the case of the M-40 urban ring for the city of Madrid.

Real-time bilateral control of a nonlinear teleoperation system

In this work, we study the bilateral control of a nonlinear teleoperator system with constant delay, proposes a control strategy by state convergence, which directly connect the local and remote manipulator through feedback signals of position and speed. The control signal allows the remote manipulator follow the local manipulator through the state convergence even if it has a delay in the communication channel. The bilateral control of the teleoperator system considers the case when the human operator applies a constant force on the local manipulator and when the interaction of the remote manipulator with the environment is considered passive. The stability analysis is performed using functional of Lyapunov-Krasovskii, it showed that using a control algorithm by state convergence for the case with constant delay, the nonlinear local and remote teleoperation system is asymptotically stable, also speeds converge to zero and position tracking is achieved.