Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The use of image processing systems is becoming frequent and is appropriate in edge computing. However, the demands on power consumption and high performance prevent the use of standard processing platforms. Thus, FPGAs are a good option for the development of computer vision systems because they are capable of exploiting parallelism. On the other hand, the design flow of current FPGA synthesis tools supports high-level languages as input descriptions, in contrast to hardware description languages. High-level synthesis (HLS) automates the design process by transforming an algorithmic description into digital hardware meeting design limitations. However, image processing experts may find challenging the hardware integration with the rest of the system components, e.g. capture and display interfaces. This work presents a basic design for the construction of image processing applications based on Zynq and a guide for its use, which solves this problem, allowing the agile generation of embedded image processing solutions. Additionally, a methodology is provided, which facilitates the efficient development of image processing embedded solutions in an agile way.

Optoacoustic imaging is a hybrid technique that benefits from both the versatile optical contrast and the high spatial resolution associated with the low propagation dispersion of ultrasonic waves. Usually, high energy lasers (> 10 mJ) are used as a light source which are expensive, non-portable and have a low repetition rate (~20 Hz). In recent years, the use of light-emitting diodes (LEDs) as substitute has been studied because of they are less expensive, more reliable and compact, and they can provide thousands of pulses in a second for real-time imaging. This paper presents the implementation of an illumination system based on LEDs and the embedded system EDU-CIAA. The developed system is capable of emitting short light pulses (< 1 us) with great intensity and high frequency (> 1 kHz).

The representation system in modern radars is carried out by obtaining digital signals. In the case of tracking radars, the representation is updated in the order of tenths of a millisecond. In order to achieve to update the display in real time, the acquisition, processing and representation process must comply with the time requirement imposed by the radar. The objective of this work is the visualization of the information for a medium of this type in real time using the Odroid XU4 board. For their solution, the parallel programming method was used, through the creation of threads in the Qt Creator Integrated Development Environment and the use of the "cauce" segmentation parallel programming pattern. The result allowed an efficient use of computing resources, obtaining a decrease of the execution time and a greater acceleration with respect to the sequential variant.

The use of WiFi is widely used by a large number of devices, including those that make up the Internet of Things (IoT) and Artificial Intelligence (AI) systems. The location problem has been under investigation for a long time. In some cases, the radio signals used to transmit information are also used to make position estimates. However, its use is affected by the constant fluctuation of the signal. It is possible that when estimating the position of a component, it is influenced by obstacles, multipath and signal reflection. Its use improves when spatial localization is carried out, where assets can be traced within an indoor environment. In this work, the relationship of the distance estimation algorithms using RSSI and triangulation is analyzed, and a solution based on Neural Networks is proposed that combines the results of three distance estimation algorithms in order to increase precision.

A communication architecture is presented to enable cloud services around agricultural machinery in rural areas with limited connectivity infrastructure. This architecture is made up of three modules named: on-board unit, gateway and cloud service. Which together allow extending the scope of communication coverage, enabling the exchange of data from agricultural machinery to the cloud. The architecture is developed using low-cost hardware and open-source libraries that allow its rapid implementation. The results obtained, in terms of communication latency, indicate that the solution is suitable for monitoring applications in agricultural machinery using ISOBUS.

In embedded systems a wide variety of applications can be solved or approached using different technologies, such as microcontrollers, FPGA, Systems on Chip (SoC), among others. Even though the volume of information and solutions available that focus on low cost based microcontrollers is quite vast, FPGA and SoC do not have as many resources readily available despite being essential for critical applications and also those in which higher speeds for data processing are required. Not only that, but the high cost of development boards, discontinuity between contents taught in higher education and knowledge required in practical fields, and overall lack of learning resources all add difficulty to any professional looking to specialize themselves in this field of knowledge. It is for this reason that this work proposes an Open Platform for Digital Design Learning on FPGA-based Systems, which looks to facilitate the learning process for any student or professional that wants to get started in this field. For this purpose this work proposes the following: a low-cost development board alongside a set of learning tools and examples which can fit both self-taught students and lecture-based learning environments, and the creation of a national collaboration network to give support to students and teachers who want to join and participate in the project.

The increasing complexity in today’s systems and the limited market times demand new development tools for FPGA. Currently, in addition to traditional hardware description languages (HDLs), there are high level synthesis (HLS) tools that increase the abstraction level in system development. Despite the greater simplicity of design and testing, HLS has some drawbacks in describing hardware. This paper presents a comparative study between HLS and HDL for FPGA, using a Sobel filter as a case study in the image processing field. The results show that the HDL implementation is slightly better than the HLS version considering resource usage and response time. However, the programming effort required in the HDL solution is significantly larger than in the HLS counterpart.

This work presents the materials and parameters selection criteria of wedge cells for refractometry in the visible range. These cells consist of two right angle prisms facing each other, defining a wedge-shaped cavity where the sample is placed. The refractive index of the sample is determined from the deviation of a light beam that traverses the cell. This model for engineering purposes includes the cell geometry and the refractive indexes of the cell material and the sample. We perform the numerical calculation and ray tracing of the optical system. We also propose polinomial fitting functions in order to simplify the numerical treatment, and as a complement to the complete set of equations. These polynomials give the refractive index of the sample as an explicit function of the deviation angle. An analysis of the approximation errors is also given.

This paper presents the development of an automated electric generators test bench for low power wind energy in urban applications. The bench allows testing electric generator under similar operating conditions to real, electric generator coupled to a wind turbine in urban environments, which allows to determine specific parameters: electric current, voltage, power.

This paper describes the implementation of a digital spectrogram on an embedded system, with the aim of allowing the visualization of the effects of applying digital filters and Fast Fourier Transform over a signal. The FreeRTOS operating system was used to facilitate the management of processing resources.