IFAC Journal of Systems and Control最新文献

{"title":"On the terminal conditions of the two cutters and a fugitive ship differential game with non-zero capture radius and different players’ speed ratio","authors":"Eliezer Lozano ,&nbsp;Israel Becerra ,&nbsp;Ubaldo Ruiz ,&nbsp;Rafael Murrieta-Cid","doi":"10.1016/j.ifacsc.2024.100273","DOIUrl":"https://doi.org/10.1016/j.ifacsc.2024.100273","url":null,"abstract":"<div><p>We study a pursuit-evasion differential game in which three agents move with simple motion on the Euclidean plane. Two of them, the cutters (pursuers), aim to capture a fugitive ship (the evader) as soon as possible. Having an opposite goal, the fugitive ship seeks to avoid capture for as long as possible. The game ends when the distance between the fugitive and at least one of the cutters is smaller than a given value. We have divided the game into two cases: case 1, when all players have the same speed, and case 2, when the evader is faster than the pursuers. Unlike previous work, our main innovations are as follows. For case 1, we present a solution obtained using exclusively differential game techniques. The game of kind is solved by establishing a study of the barrier that defines the winner of the game. In addition, we obtained time-optimal strategies for all players, proving that they do not switch controls. For case 2, we obtain the primary solution and exhibit an example showing the existence of control switches.</p></div>","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"29 ","pages":"Article 100273"},"PeriodicalIF":1.8,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141605463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Periodic output regulation for 1-D wave equation subject to non-collocated control","authors":"Jing Wei ,&nbsp;Bao-Zhu Guo","doi":"10.1016/j.ifacsc.2024.100271","DOIUrl":"https://doi.org/10.1016/j.ifacsc.2024.100271","url":null,"abstract":"<div><p>In this paper, we focus on the periodic output regulation for a one-dimensional wave equation where the performance output is non-collocated with the control input. The exosystems considered here are multi-periodic time-varying, capable of generating periodic reference signals and disturbances within the domain and at the boundaries, each with distinct periods. Initially, a backstepping-based state feedback regulator is designed by tackling an ill-posed periodic regulator equation. Subsequently, leveraging an external matrix, we design a novel time-varying observer tailored for the transformed wave equation and the exosystems. An output feedback regulator is then obtained by replacing the states with their estimations. The tracking error is shown to decay exponentially and the closed-loop system is proved to be bounded. Some numerical simulations are presented to validate the results.</p></div>","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"29 ","pages":"Article 100271"},"PeriodicalIF":1.8,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141542367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An extension of Pontryagin Maximum principle in interval environment and its application to inventory problem","authors":"Subhajit Das ,&nbsp;Fleming Akhtar ,&nbsp;Ali Akbar Shaikh ,&nbsp;Asoke Kumar Bhunia","doi":"10.1016/j.ifacsc.2024.100269","DOIUrl":"https://doi.org/10.1016/j.ifacsc.2024.100269","url":null,"abstract":"<div><p>The control theory is one of the most fundamental branches of engineering as it implicates solving abilities of numerous non-linear engineering design problems efficiently. Again, Pontryagin’s maximum principle is one of the most salient topics of control theory as it is involved in solving various important problems. However, in the current highly complex situation, most of such real-life problems appear to be highly uncertain/imprecise in nature. Consequently, in order to analyse such problems accurately, uncertainty/flexibility of such problems cannot be overestimated. Motivating from this fact and as a necessity, in this study, the Pontryagin’s maximum principles are extended in interval environment for interval valued control problems (IVCPs). In this context, an IVCP is defined along with different formal terminologies. Further, the necessary and sufficient optimality conditions (i.e., Pontryagin’s maximum principles) are extended for IVCPs using existing interval ranking proposed by Bhunia and Samanta (2014). Further, in the second part of this work, in order to test the effectiveness of the proposed theories, an economic order quantity (EOQ) model is developed by considering dynamic servicing strategies in interval environment. With the help of numerical example, the proposed extension of Pontryagin’s maximum principles for IVCPs is well validated.</p></div>","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"29 ","pages":"Article 100269"},"PeriodicalIF":1.8,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141485098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Periodic event-triggered controller design with Bayesian optimization: An emulation-based approach","authors":"Kazumune Hashimoto","doi":"10.1016/j.ifacsc.2024.100268","DOIUrl":"https://doi.org/10.1016/j.ifacsc.2024.100268","url":null,"abstract":"<div><p>In recent years, event-triggered control has emerged as a promising strategy for addressing resource constraints in networked control systems (NCSs), such as limited life-time of battery capacity. This paper explores the development of a periodic event-triggered controller through a model-free design, assuming unknown plant dynamics. The design of the event-triggered controller employs an emulation-based approach, which is divided into solving two sub-problems: the problem for designing parameters for the time-triggered (periodic) control law, and the problem for designing parameters for the event-triggered condition. In particular, both problems will be solved through the usage of two distinct Bayesian optimization algorithms. The first problem is addressed by adapting basic Bayesian optimization to include network utilization by considering the number of communication time steps during optimization. The second problem employs constrained Bayesian optimization to incorporate explicit performance constraints within the optimization process. A numerical example is provided to demonstrate the effectiveness of the proposed method.</p></div>","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"29 ","pages":"Article 100268"},"PeriodicalIF":1.8,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468601824000294/pdfft?md5=95ecdae280220065b1b21000b77a16fc&pid=1-s2.0-S2468601824000294-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141593047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis on the contribution of glucagon receptors to glucose dynamics in type 1 diabetes","authors":"Clara Furió-Novejarque ,&nbsp;Iván Sala-Mira ,&nbsp;Ajenthen G. Ranjan ,&nbsp;Kirsten Nørgaard ,&nbsp;José-Luis Díez ,&nbsp;John Bagterp Jørgensen ,&nbsp;Jorge Bondia","doi":"10.1016/j.ifacsc.2024.100272","DOIUrl":"https://doi.org/10.1016/j.ifacsc.2024.100272","url":null,"abstract":"<div><p>The glucagon effect is understudied in type 1 diabetes (T1D) simulators, without a clear consensus on the pharmacodynamics of glucagon over glucose. Glucagon receptors dynamics could present a significant contribution to T1D simulators, making them more physiologically accurate without an excessive increase in complexity. This work analyzes the receptors model contributions to glucose dynamics using a model proposed in previous work. Then, the model is assessed from two different perspectives: (1) A clinical dataset of the influence of diet (high or low carbohydrate content) on two consecutive glucagon doses (100 and 500 <span><math><mi>μ</mi></math></span>g) is used to identify the model parameters and (2) three other glucagon action models from the literature are also identified to serve as comparators. Different identification methods are used to adapt to the distinctive features of the dataset. The root mean square error (RMSE) and the Akaike Information Criterion (AIC) were the discerning metrics used to compare the models fittings. Results show that the receptors model offers the lowest RMSE and AIC in contrast to the comparators. This model will hence be helpful in the development of accurate T1D simulators.</p></div>","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"29 ","pages":"Article 100272"},"PeriodicalIF":1.8,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468601824000336/pdfft?md5=07540efc7b5c2f9fadcad4a006bc0cea&pid=1-s2.0-S2468601824000336-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141485099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving breathing effort estimation in mechanical ventilation via optimal experiment design","authors":"Lars van de Kamp ,&nbsp;Bram Hunnekens ,&nbsp;Nathan van de Wouw ,&nbsp;Tom Oomen","doi":"10.1016/j.ifacsc.2024.100270","DOIUrl":"https://doi.org/10.1016/j.ifacsc.2024.100270","url":null,"abstract":"<div><p>Estimation of the breathing effort and relevant lung parameters of a ventilated patient is essential to keep track of a patient’s clinical condition. The aim of this paper is to increase estimation accuracy through experiment design. The main method is an experiment design approach across multiple breaths within a linear regression framework to accurately identify the patient’s condition. Identifiability and persistence of excitation are used to formulate an estimation problem with a unique solution. Furthermore, Fisher information is used for assessing the parameters sensitivity to slight changes of the ventilator settings to improve the variance of the estimation. The estimation method is applied to simulated patients who breathe regularly but also to patients who have variable breathing patterns. A virtual experiment is conducted for both situations to generate estimation results. The results are analyzed using mathematical tools and show that uniquely estimating the lung parameters and breathing effort over multiple breaths for both regularly and variably breathing patients is possible in the presented framework. The proposed estimation method obtains clinically relevant estimates for a large set of breathing disturbances from the simulation case-study.</p></div>","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"29 ","pages":"Article 100270"},"PeriodicalIF":1.8,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468601824000312/pdfft?md5=0dc0c78986490c9389178bb450258316&pid=1-s2.0-S2468601824000312-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141542368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ellipsoidal estimation of motion parameters of a non-cooperative space vehicle from visual information","authors":"Nikolay Salnikov ,&nbsp;Serhii Melnychuk ,&nbsp;Vyacheslav Gubarev ,&nbsp;Oleksii Sholokhov","doi":"10.1016/j.ifacsc.2024.100267","DOIUrl":"10.1016/j.ifacsc.2024.100267","url":null,"abstract":"<div><p>The use of near-Earth space is currently complicated by presence of space debris objects in Earth’s orbit, which include spent stages of launch vehicles, inoperative satellites, and other large and small artificial objects. One approach to solving the problem of space debris involves docking and capturing a non-cooperative space object or spacecraft (target) with a so-called service spacecraft (chaser) for further actions to repair, refuel or change its orbit. Rendezvous and docking are complicated by the rotation of uncontrolled space objects caused by various factors. To perform this task, it is necessary to know the parameters of the orbital, rotational and relative motion of the target. The parameters of the orbital motion of such objects are usually known quite accurately from measurements from the Earth. This paper examines the case of a tumbling non-cooperative target located in an elliptical orbit. It is assumed that the target relative position and orientation are measured by the computer vision system (CVS) of the chaser. In this case, the position and orientation of the graphical reference frame (GRF) associated with the known 3-D graphical model of the target are determined relative to the reference frame associated with the chaser. The specific type of CVS is not considered. It is assumed that the chaser can carry out some maneuvers near the target and all parameters of the chaser angular motion are known. Thus, the attitude of the GRF relative to inertial reference frame (IRF) can be determined. The measured parameters are not enough to ensure safe rendezvous and docking with the target. To complete this task, it is necessary to determine all kinematic and dynamic parameters of the relative motion between the spacecraft. The rest of the required parameters are estimated. Orientation and rotation parameterization is done using quaternions. The angular motion equation of the target is considered in the GRF. This makes the angular velocity estimation faster and the inertia tensor estimation more stable. Stochastic characteristics of measurement errors are considered to be unknown and are not used. The only information about the errors is the bounds of their values. To determine the relative motion parameters, we use a new dynamic set-membership filter with ellipsoidal estimates. The filter can be successfully implemented on low-power on-board processors. The properties of the proposed algorithm are demonstrated using numerical simulation. The results obtained are expected to be used in the development of a navigation system for the rendezvous and docking, developed by a group of Ukrainian space industry enterprises under the leadership of the LLC “Kurs-orbital” (<span>https://kursorbital.com/</span><svg><path></path></svg>).</p></div>","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"29 ","pages":"Article 100267"},"PeriodicalIF":1.8,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141398130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring variable observational time windows for patient–ventilator​ asynchrony during mechanical ventilation treatment","authors":"Christopher Yew Shuen Ang ,&nbsp;Yeong Shiong Chiew ,&nbsp;Xin Wang ,&nbsp;Ean Hin Ooi ,&nbsp;Mohd Basri Mat Nor ,&nbsp;Matthew E. Cove ,&nbsp;J. Geoffrey Chase","doi":"10.1016/j.ifacsc.2024.100266","DOIUrl":"https://doi.org/10.1016/j.ifacsc.2024.100266","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Background and Objective:&lt;/h3&gt;&lt;p&gt;Patient–ventilator asynchrony (PVA) is prevalent in mechanical ventilation (MV) for critically ill patients and has been associated with adverse patient outcomes. However, studies investigating the associations between PVA and patient outcomes employ differing time windows for PVA evaluation. In this study, machine learning methods are used to quantify the prevalence and magnitude of asynchrony at different time windows, as well as its temporal trends. The study aims to identify the optimal time window for assessing the temporal changes in the asynchrony index (AI) and magnitude of asynchrony (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;).&lt;/p&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods:&lt;/h3&gt;&lt;p&gt;This study uses Convolutional Neural Networks (CNN) and Convolutional Autoencoders (CAE) to detect incidences of PVA and quantify its severity in 30 MV respiratory failure patients with 2722 h of respiratory data. The frequency of PVA and the breath-average magnitude were determined over different time periods, &lt;em&gt;t&lt;/em&gt;, where &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 45, 60 min and throughout MV. The AI for the patients was determined using the CNN model. Given an asynchronous breath, the CAEs were used to reconstruct asynchrony-free waveforms. The &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; was quantified as the difference between the two waveforms. The change in AI (&lt;span&gt;&lt;math&gt;&lt;mi&gt;Δ&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;AI) and the change in &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;\u0000(&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;Δ&lt;/mi&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;) for all time windows, &lt;em&gt;t&lt;/em&gt; were also calculated for each patient.&lt;/p&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results:&lt;/h3&gt;&lt;p&gt;The median [interquartile range] overall AI and &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; for the patient cohort are 24.8 [12.9–46.1]% and 37.2 [33.4–45.3]% respectively. Analysis of the patient cohort also shows significant intra-patient variability in AI and &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, while the inter-patient variation in AI is greater as compared to &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;. The cohort mean &lt;span&gt;&lt;math&gt;&lt;mi&gt;Δ","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"29 ","pages":"Article 100266"},"PeriodicalIF":1.9,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468601824000270/pdfft?md5=094888b14f6d15c2cd2308a4be54717c&pid=1-s2.0-S2468601824000270-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141303150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrode module for EIT with a robust howland current source","authors":"Rafael B. Santos ,&nbsp;André L. Santos ,&nbsp;André C.M. Cavalheiro ,&nbsp;Rafael A.O. Ferro ,&nbsp;Fernando S. Moura ,&nbsp;Raul G. Lima ,&nbsp;Thiago C. Martins ,&nbsp;Marcos S.G. Tsuzuki","doi":"10.1016/j.ifacsc.2024.100265","DOIUrl":"10.1016/j.ifacsc.2024.100265","url":null,"abstract":"<div><p>Electrical Impedance Tomography (EIT) is a non-invasive imaging technique that reconstructs internal conductivity distributions of a body from electrical measurements taken on its boundary. This study contributes to the field by focusing on the technological intricacies of absolute EIT imaging, which is challenged by limitations such as the resolution capacity of the hardware and the complexities introduced by imaging capacitive bodies. The novel EIT system architecture proposed enhances the accuracy of measurement by integrating current sources and Analog-to-Digital Converters (ADCs) closer to the electrodes, employing alternating current excitations to accurately capture phase information. This system uses a dynamic arrangement of surface electrodes that continuously alter their roles between current injection and voltage measurement, in a synchronized sequence, to ensure the accuracy of the measurements. The paper describes the design and implementation of both the excitation and measurement subsystems, highlighting the use of digital signal demodulation near the electrode to reduce data transfer issues. Experimental results confirm the system’s capability for real-time image reconstruction at 50 frames per second with precision in phase delay measurements, suggesting significant potential for clinical and industrial applications. Future work will aim to further refine signal generation with higher-speed DACs and expand to image reconstruction with more channels.</p></div>","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"28 ","pages":"Article 100265"},"PeriodicalIF":1.9,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141143207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing and minimizing the impact of an additive disturbance for human respiratory system impedance estimation","authors":"Antoine Marchal ,&nbsp;Andy Keymolen ,&nbsp;Gerd Vandersteen ,&nbsp;Frank Heck ,&nbsp;Ben van den Elshout ,&nbsp;John Lataire","doi":"10.1016/j.ifacsc.2024.100264","DOIUrl":"https://doi.org/10.1016/j.ifacsc.2024.100264","url":null,"abstract":"<div><p>Respiratory Oscillometry is a promising technique to provide information to medical practitioners on the respiratory system of a patient in a non-invasive fashion. It focuses on identifying the respiratory impedance between two signals: the air pressure and flow at the mouth opening. However, for conscious patients or lightly sedated ventilated patients, their respiratory effort such as breathing acts as a disturbance to the parameter estimation procedure. This paper is an extension to previous research published at the IFAC 2023 World Congress (Marchal et al., 2023) that proposed a method to estimate and remove this breathing disturbance using Gaussian Process Regression in the frequency domain. In this extension, Monte Carlo simulations are performed to validate the approach and to compare it to the Local Polynomial Method for breathing patients. In addition, measurements carried out on a lung emulator in a pressure-support ventilation mode provide further evidence of the method’s effectiveness at dealing with the disturbance experienced for ventilated patients. This is a step towards treating both breathing and ventilated patients using the same technique.</p></div>","PeriodicalId":29926,"journal":{"name":"IFAC Journal of Systems and Control","volume":"29 ","pages":"Article 100264"},"PeriodicalIF":1.9,"publicationDate":"2024-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141323364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}