Open-source low-cost Hardware-in-the-loop simulation platform for testing control strategies for artificial pancreas research

Current technological advances have brought closer to reality the project of a safe, portable, and efficient artificial pancreas for people with type 1 diabetes (T1D). Among the developed control strategies for T1D, model predictive control (MPC) has been emphasized in literature as a promising control for glucose regulation. However, these control strategies are commonly designed in a computer environment, regardless of the limitations of a portable device. In this paper, the performances of six embedded platforms and three open-source optimization solver algorithms are assessed for T1D treatment. Their advantages and limitations are clarified using four MPC formulations of increasing complexity and a hardware-in-the-loop methodology to evaluate glucose control in virtual adult subjects. The performance comparison includes the execution time, the difference concerning the evolution obtained in MATLAB, the processor temperature, energy consumption, time percentage in normoglycemia, and the number of hypo- and hyperglycemic events. Results show that Quadprog is the package that faithfully follows the results obtained with control strategies designed and tuned on a computer with the MATLAB software. In addition, the Raspberry Pi 3 and the Tinker Board S embedded systems present the appropriate characteristics to be implemented as portable devices in the artificial pancreas application according to the criteria set out in this work.

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Low-Cost Hardware-in-the-Loop Platform for Embedded Control Strategies Simulation

IEEE Access ◽

10.1109/access.2019.2934420 ◽

2019 ◽

Vol 7 ◽

pp. 111499-111512 ◽

Cited By ~ 4

Author(s):

Alceu Bernardes Castanheira De Farias ◽

Reurison Silva Rodrigues ◽

Andre Murilo ◽

Renato Vilela Lopes ◽

Suzana Avila

Keyword(s):

Control Strategies ◽

Low Cost ◽

Hardware In The Loop ◽

Embedded Control

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PHiLIP on the HiL: Automated Multi-Platform OS Testing With External Reference Devices

ACM Transactions on Embedded Computing Systems ◽

10.1145/3477040 ◽

2021 ◽

Vol 20 (5s) ◽

pp. 1-26

Author(s):

Kevin Weiss ◽

Michel Rottleuthner ◽

Thomas C. Schmidt ◽

Matthias Wählisch

Keyword(s):

Open Source ◽

Performance Metrics ◽

Resource Constraints ◽

Low Cost ◽

Hardware In The Loop ◽

Test Environment ◽

Specific Test ◽

Continuous Evolution ◽

External Reference ◽

Practical Experiences

Developing an operating systems (OSs) for low-end embedded devices requires continuous adaptation to new hardware architectures and components, while serviceability of features needs to be assured for each individual platform under tight resource constraints. It is challenging to design a versatile and accurate heterogeneous test environment that is agile enough to cover a continuous evolution of the code base and platforms. This mission is even more challenging when organized in an agile open-source community process with many contributors such as for the RIOT OS. Hardware in the Loop (HiL) testing and Continuous Integration (CI) are automatable approaches to verify functionality, prevent regressions, and improve the overall quality at development speed in large community projects. In this paper, we present PHiLIP (Primitive Hardware in the Loop Integration Product), an open-source external reference device together with tools that validate the system software while it controls hardware and interprets physical signals. Instead of focusing on a specific test setting, PHiLIP takes the approach of a tool-assisted agile HiL test process, designed for continuous evolution and deployment cycles. We explain its design, describe how it supports HiL tests, evaluate performance metrics, and report on practical experiences of employing PHiLIP in an automated CI test infrastructure. Our initial deployment comprises 22 unique platforms, each of which executes 98 peripheral tests every night. PHiLIP allows for easy extension of low-cost, adaptive testing infrastructures but serves testing techniques and tools to a much wider range of applications.

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Rapid mapping accuracy assessment using low-cost UAV and open-source Structure from Motion

Rendiconti online della Società Geologica Italiana ◽

10.3301/rol.2020.19 ◽

2020 ◽

Vol 52 ◽

pp. 55-61

Author(s):

Ettore Potente ◽

Cosimo Cagnazzo ◽

Alessandro Deodati ◽

Giuseppe Mastronuzzi

Keyword(s):

Open Source ◽

Structure From Motion ◽

Accuracy Assessment ◽

Low Cost ◽

Mapping Accuracy ◽

Rapid Mapping ◽

Source Structure

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PyDOSS: An open-source Python-based communicable disease outbreak surveillance system designed and used in a COVID-19 community care facility (Preprint)

10.2196/preprints.21760 ◽

2020 ◽

Author(s):

Andrew Fang ◽

Jonathan Kia-Sheng Phua ◽

Terrence Chiew ◽

Daniel De-Liang Loh ◽

Lincoln Ming Han Liow ◽

...

Keyword(s):

Open Source ◽

Surveillance System ◽

Community Care ◽

Communicable Disease ◽

Low Cost ◽

Real Life ◽

Disease Outbreak ◽

Disease Spread ◽

Healthcare Team ◽

Increased Risk

BACKGROUND During the Coronavirus Disease 2019 (COVID-19) outbreak, community care facilities (CCF) were set up as temporary out-of-hospital isolation facilities to contain the surge of cases in Singapore. Confined living spaces within CCFs posed an increased risk of communicable disease spread among residents. OBJECTIVE This inspired our healthcare team managing a CCF operation to design a low-cost communicable disease outbreak surveillance system (CDOSS). METHODS Our CDOSS was designed with the following considerations: (1) comprehensiveness, (2) efficiency through passive reconnoitering from electronic medical record (EMR) data, (3) ability to provide spatiotemporal insights, (4) low-cost and (5) ease of use. We used Python to develop a lightweight application – Python-based Communicable Disease Outbreak Surveillance System (PyDOSS) – that was able perform syndromic surveillance and fever monitoring. With minimal user actions, its data pipeline would generate daily control charts and geospatial heat maps of cases from raw EMR data and logged vital signs. PyDOSS was successfully implemented as part of our CCF workflow. We also simulated a gastroenteritis (GE) outbreak to test the effectiveness of the system. RESULTS PyDOSS was used throughout the entire duration of operation; the output was reviewed daily by senior management. No disease outbreaks were identified during our medical operation. In the simulated GE outbreak, PyDOSS was able to effectively detect an outbreak within 24 hours and provided information about cluster progression which could aid in contact tracing. The code for a stock version of PyDOSS has been made publicly available. CONCLUSIONS PyDOSS is an effective surveillance system which was successfully implemented in a real-life medical operation. With the system developed using open-source technology and the code made freely available, it significantly reduces the cost of developing and operating CDOSS and may be useful for similar temporary medical operations, or in resource-limited settings.

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Power Hardware-in-the-Loop-Based Performance Analysis of Different Converter Controllers for Fast Active Power Regulation in Low-Inertia Power Systems

Energies ◽

10.3390/en14113274 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3274

Author(s):

Jose Rueda Torres ◽

Zameer Ahmad ◽

Nidarshan Veera Kumar ◽

Elyas Rakhshani ◽

Ebrahim Adabi ◽

...

Keyword(s):

Performance Evaluation ◽

Power Systems ◽

Real Time ◽

Control Strategies ◽

Active Power ◽

Power Electronic ◽

Hardware In The Loop ◽

Digital Controllers ◽

Power Regulation ◽

The Impact

Future electrical power systems will be dominated by power electronic converters, which are deployed for the integration of renewable power plants, responsive demand, and different types of storage systems. The stability of such systems will strongly depend on the control strategies attached to the converters. In this context, laboratory-scale setups are becoming the key tools for prototyping and evaluating the performance and robustness of different converter technologies and control strategies. The performance evaluation of control strategies for dynamic frequency support using fast active power regulation (FAPR) requires the urgent development of a suitable power hardware-in-the-loop (PHIL) setup. In this paper, the most prominent emerging types of FAPR are selected and studied: droop-based FAPR, droop derivative-based FAPR, and virtual synchronous power (VSP)-based FAPR. A novel setup for PHIL-based performance evaluation of these strategies is proposed. The setup combines the advanced modeling and simulation functions of a real-time digital simulation platform (RTDS), an external programmable unit to implement the studied FAPR control strategies as digital controllers, and actual hardware. The hardware setup consists of a grid emulator to recreate the dynamic response as seen from the interface bus of the grid side converter of a power electronic-interfaced device (e.g., type-IV wind turbines), and a mockup voltage source converter (VSC, i.e., a device under test (DUT)). The DUT is virtually interfaced to one high-voltage bus of the electromagnetic transient (EMT) representation of a variant of the IEEE 9 bus test system, which has been modified to consider an operating condition with 52% of the total supply provided by wind power generation. The selected and programmed FAPR strategies are applied to the DUT, with the ultimate goal of ascertaining its feasibility and effectiveness with respect to the pure software-based EMT representation performed in real time. Particularly, the time-varying response of the active power injection by each FAPR control strategy and the impact on the instantaneous frequency excursions occurring in the frequency containment periods are analyzed. The performed tests show the degree of improvements on both the rate-of-change-of-frequency (RoCoF) and the maximum frequency excursion (e.g., nadir).

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Process Emulation System for High-Power Piezoelectric Ultrasonic Actuators

Energy Harvesting and Systems ◽

10.1515/ehs-2014-0036 ◽

2015 ◽

Vol 2 (3-4) ◽

pp. 201-205

Author(s):

Igor Ille ◽

Sebastian Mojrzisch ◽

Jens Twiefel

Keyword(s):

Feedback Control ◽

Low Cost ◽

Stable Process ◽

Present System ◽

Wide Field ◽

Hardware In The Loop ◽

Ultrasonic Assisted ◽

Long Time ◽

Number Of Cycles ◽

High Flexibility

Abstract Ultrasonic actuators are used for a wide field of applications. The vibration energy can be used to realize many processes like ultrasonic welding or bonding. Furthermore there are many processes which run more efficient and faster combined with ultrasonic vibration like ultrasonic-assisted turning or drilling. Piezoelectric transducers are the main part of those applications. Most of the applications have a time-variant load behavior and need an amplitude feedback control to guarantee a stable process. To ensure correct function tests of the feedback control systems have to be done. In this case the processes have to be executed in association with a high number of cycles. To emulate the behavior of the environment the automotive and aerospace industries use hardware in the loop systems since a long time but there is no such a method for ultrasonic systems. This paper presents a method to realize high dynamic load emulation for different ultrasonic applications. Using a piezoelectric transformer it is possible to reproduce load curves by active damping on the secondary side of the transformer using a current proportional digital feedback circuit. A theoretical and experimental study of hardware in the loop system for ultrasonic applications is given by this paper. The present system allows testing a wide field of feedback control algorithms with high flexibility and a high number of cycles by utilization of low-cost components. This proceeding decreases design periods in association with feedback control.

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Power Hardware-in-the-Loop: Response of Power Components in Real-Time Grid Simulation Environment

Energies ◽

10.3390/en14030593 ◽

2021 ◽

Vol 14 (3) ◽

pp. 593

Author(s):

Moiz Muhammad ◽

Holger Behrends ◽

Stefan Geißendörfer ◽

Karsten von Maydell ◽

Carsten Agert

Keyword(s):

Real Time ◽

Power Distribution ◽

Control Strategies ◽

Power Grid ◽

Energy System ◽

Hardware In The Loop ◽

Distribution Grid ◽

Compensation Strategy ◽

Software Environment ◽

The Real

With increasing changes in the contemporary energy system, it becomes essential to test the autonomous control strategies for distributed energy resources in a controlled environment to investigate power grid stability. Power hardware-in-the-loop (PHIL) concept is an efficient approach for such evaluations in which a virtually simulated power grid is interfaced to a real hardware device. This strongly coupled software-hardware system introduces obstacles that need attention for smooth operation of the laboratory setup to validate robust control algorithms for decentralized grids. This paper presents a novel methodology and its implementation to develop a test-bench for a real-time PHIL simulation of a typical power distribution grid to study the dynamic behavior of the real power components in connection with the simulated grid. The application of hybrid simulation in a single software environment is realized to model the power grid which obviates the need to simulate the complete grid with a lower discretized sample-time. As an outcome, an environment is established interconnecting the virtual model to the real-world devices. The inaccuracies linked to the power components are examined at length and consequently a suitable compensation strategy is devised to improve the performance of the hardware under test (HUT). Finally, the compensation strategy is also validated through a simulation scenario.

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An Agent-Based Crop Model Framework for Heterogeneous Soils

Agronomy ◽

10.3390/agronomy11010085 ◽

2021 ◽

Vol 11 (1) ◽

pp. 85

Author(s):

Jorge Lopez-Jimenez ◽

Nicanor Quijano ◽

Alain Vande Wouwer

Keyword(s):

Growth Models ◽

Control Strategies ◽

Low Cost ◽

Soil Heterogeneity ◽

Crop Growth ◽

Negative Effects ◽

Model Framework ◽

Agent Based ◽

Crop Growth Models ◽

Definition Of

Climate change and the efficient use of freshwater for irrigation pose a challenge for sustainable agriculture. Traditionally, the prediction of agricultural production is carried out through crop-growth models and historical records of the climatic variables. However, one of the main flaws of these models is that they do not consider the variability of the soil throughout the cultivation area. In addition, with the availability of new information sources (i.e., aerial or satellite images) and low-cost meteorological stations, it is convenient that the models incorporate prediction capabilities to enhance the representation of production scenarios. In this work, an agent-based model (ABM) that considers the soil heterogeneity and water exchanges is proposed. Soil heterogeneity is associated to the combination of individual behaviours of uniform portions of land (agents), while water fluxes are related to the topography. Each agent is characterized by an individual dynamic model, which describes the local crop growth. Moreover, this model considers positive and negative effects of water level, i.e., drought and waterlogging, on the biomass production. The development of the global ABM is oriented to the future use of control strategies and optimal irrigation policies. The model is built bottom-up starting with the definition of agents, and the Python environment Mesa is chosen for the implementation. The validation is carried out using three topographic scenarios in Colombia. Results of potential production cases are discussed, and some practical recommendations on the implementation are presented.

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Implementation of a Six-Layer Smart Factory Architecture with Special Focus on Transdisciplinary Engineering Education

Sensors ◽

10.3390/s21092944 ◽

2021 ◽

Vol 21 (9) ◽

pp. 2944

Author(s):

Benjamin James Ralph ◽

Marcel Sorger ◽

Benjamin Schödinger ◽

Hans-Jörg Schmölzer ◽

Karin Hartl ◽

...

Keyword(s):

Open Source ◽

User Interfaces ◽

Industrial Revolution ◽

Low Cost ◽

Material Behavior ◽

Sensor Data ◽

Management Tool ◽

Special Focus ◽

Programming Environments ◽

Metal Processing

Smart factories are an integral element of the manufacturing infrastructure in the context of the fourth industrial revolution. Nevertheless, there is frequently a deficiency of adequate training facilities for future engineering experts in the academic environment. For this reason, this paper describes the development and implementation of two different layer architectures for the metal processing environment. The first architecture is based on low-cost but resilient devices, allowing interested parties to work with mostly open-source interfaces and standard back-end programming environments. Additionally, one proprietary and two open-source graphical user interfaces (GUIs) were developed. Those interfaces can be adapted front-end as well as back-end, ensuring a holistic comprehension of their capabilities and limits. As a result, a six-layer architecture, from digitization to an interactive project management tool, was designed and implemented in the practical workflow at the academic institution. To take the complexity of thermo-mechanical processing in the metal processing field into account, an alternative layer, connected with the thermo-mechanical treatment simulator Gleeble 3800, was designed. This framework is capable of transferring sensor data with high frequency, enabling data collection for the numerical simulation of complex material behavior under high temperature processing. Finally, the possibility of connecting both systems by using open-source software packages is demonstrated.

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