http://hdl.handle.net/2117/7276 2013-05-25T07:29:05Z http://hdl.handle.net/2117/14313 Title: Design of an embedded control system laboratory experiment Authors: Martí Colom, Pau; Velasco García, Manel; Fuertes Armengol, José Mª; Camacho Santiago, Antonio; Buttazzo, Giorgio Abstract: This paper presents a prototype laboratory experiment to be integrated in the education of embedded control system engineers. The experiment, a real-time control of a dynamical system, is designed to drive students to a deeper understanding and integration of the diverse theoretical concepts that often come from different disciplines such as real-time systems and control systems. Rather than proposing the experiment for a particular course within an embedded system engineering curriculum, this paper describes how the experiment can be tailored to the needs and diverse background of both undergraduate and graduate students education. 2011-12-22T13:08:12Z http://hdl.handle.net/2117/10314 Title: Simulation study of a remote wireless path tracking control with delay estimation for an autonomous guided vehicle Authors: Lozoya, Camilo; Martí Colom, Pau; Velasco García, Manel; Fuertes Armengol, José Mª; Martín Rull, Enric Xavier Abstract: Industrial applications involving mobile systems can benefit from the use of wireless technology. However, wireless communication has not been widely accepted on the factory floor due to its difficulty in achieving the timely and reliable transmission of messages over error-prone wireless channels. This paper presents an autonomous guided vehicle (AGV) path tracking wireless control system where an accurate delay estimation scheme is shown to be the key for successful operation. The control architecture consists on an AGV connected through a wireless network to a controller. To mitigate the negative effects that varying time delays in data transfer have in the networked control loop, the controller performs two tasks at each loop operation. First, it uses a Kalman filter to produce an optimal delay estimate considering a simple stochastic model of the wireless delay dynamics. Second, each delay estimate is employed to infer the real AGV position which permits to compute the appropriate control commands. Results show that the proposed technique provides more efficient and effective operation for path tracking control compared to similar previously proposed solutions. 2010-11-16T13:11:05Z http://hdl.handle.net/2117/9812 Title: Performing flexible control on low cost microcontrollers using a minimal real-time kernel Authors: Marau, Ricardo; Leite, Paulo; Velasco García, Manel; Martí Colom, Pau; Almeida, Luis; Pedreiras, Paulo; Fuertes Armengol, José Mª Abstract: In recent years, approaches to control performance and resource optimization for embedded control systems have been receiving increased attention. Most of them focus on theory, whereas practical aspects are omitted. Theoretical advances demand flexible real-time kernel support for multitasking and preemption, thus requiring more sophisticated and expensive software/ hardware solutions. On the other hand, embedded control systems often have cost constraints related with mass production and strong industrial competition, thus demanding low-cost solutions. In this paper, it is shown that these conflicting demands can be softened and that a compromise solution can be reached. We advocate that recent research results on optimal resource management for control tasks can be implemented on simple multitasking preemptive real-time kernels targeting low-cost microprocessors, which can be easily built in-house and tailored to actual application needs. The experimental evaluation shows that significant control performance improvement can be achieved without increasing hardware costs. 2010-10-19T11:56:39Z http://hdl.handle.net/2117/9159 Title: On the timing of discrete events in event-driven control systems Authors: Velasco García, Manel; Martí Colom, Pau; Lozoya, Camilo Abstract: This paper presents an analysis method to determine offline at what intervals have to be taken the samples for various types of event- driven control systems. 2010-09-29T12:26:24Z