Control Engineering Research Articles

Effective Strain Engineering of 2D Materials via Metal Deposition.

2D materials, especially their monolayers, have garnered significant attention due to their unique electrical, optical and mechanical properties. Strain engineering is an effective way to modulate these properties. However, challenges remain in preventing slip or decoupling between the 2D material and the substrate due to the inherent weak van der Waals interactions. In this study, metal films are employed to apply strain to 2D materials. The high surface energy of metals helps to provide higher interaction forces, thereby improving strain transfer efficiency. Biaxial compressive and uniaxial tensile strain can be applied to monolayer MoS2, with the highest modulation rate of 542 and 161.7 meV/%, respectively, as characterized by photoluminescence (PL) spectra. Furthermore, this new approach can be broader to other 2D materials, such as WS2 or WSe2, allowing for precise control over strain manipulation. The work introduces a promising new approach for efficient and controllable strain engineering of 2D materials.

System to Assist the Driver During a Single Lane Change Maneuver, in the Conditions of Danger Arising from a Change in the Condition of the Road Surface

The article describes the application of a vehicle simulation model to assess the driving hazards that arise due to changes in the tyre–road adhesion during a lane change. An experimentally verified vehicle dynamics model was used. The typical single lane change maneuver, performed on dry concrete, wet concrete, and ice-covered roads, was simulated for three vehicle speeds. The disturbance was introduced as a changed tyre–road adhesion on the target lane. Typical sinusoidal (one-period) input was applied to the steering wheel. Adhesion change may lead to an accident when considering the driver’s reaction time. An original control algorithm has been built. It is the driver assistance system with a double PID controller of the steering wheel angle. The system parameters were determined based on the principles recommended in the automatic control engineering monographs. The controller fulfils its tasks for motion at very high speeds on a homogeneous road surface and for the case where the tyre–road adhesion is changed during a maneuver. Thanks to this, the threat can be avoided.

Waste plastic pyrolysis oils as diesel fuel blending components: detailed analysis of combustion and emissions sensitivity to engine control parameters

Efforts to reduce greenhouse gas emissions and ensure energy security have led to increased interest in renewable energy technologies, particularly pyrolysis for converting waste into fuel. This study examines the use of polypropylene (PPO) and polystyrene (PSO) pyrolysis oils as diesel fuel (DF) blending components. Single-cylinder engine tests were conducted on PPO and PSO, each blended with DF in mass proportions of 20%, 40% and 60%. The engine featured a state-of-the-art compression ignition combustion system, including an 8-hole high-pressure injector and precisely controlled air and exhaust gas recirculation paths. Results proved that both PPO and PSO could be efficiently combusted in modern compression ignition systems, provided their admixture with reference DF did not exceed 60%. For optimal performance, the engine control map needed to be re-calibrated to prevent over-homogenization of the pilot spray, caused by higher volatility and reduced fuel reactivity. When maximising waste-derived components, PPO provided optimal emission results (1.37 g/kWh NOX and 0.04 g/kWh PM) when combined with heavy EGR and advanced injection timing. In this case, the total emissions overlimit value was 3.7, compared to 7.3 in the best-case DF scenario (a 50% reduction in cumulative emissions). For minimizing emissions, small additions (20%) of highly volatile PSO were found to offer the greatest potential for co-optimization. Compared to the optimal DF configuration, a cumulative emissions reduction of 81% was achieved in the same calibration map region as for PPO.

An automatic 3D tomato plant stemwork phenotyping pipeline at internode level based on tree quantitative structural modelling algorithm

Phenotypic traits of stemwork are important indicators of plant growing status, contributing to multiple research domains including yield estimation, breeding engineering, and disease control. Traditional plant phenotyping with human work faces serious bottlenecks on labour intensity and time consumption. In recent years, the application of Quantitative Structural Modeling (QSM) together with three-dimensional (3D) sensor-based data acquisition techniques provides a feasible solution towards the automatic stemwork phenotyping. Nevertheless, existing QSM-based pipelines are sensitive towards the point cloud quality, and mostly focus on the phenotyping at plant or organ level. Information at internode level which are closely related to photosynthesis and light absorption was generally overlooked. To this end, a 3D automatic stemwork phenotyping pipeline is developed for tomato plants at both plant and internode level. Coloured point clouds are taken as the sensor input of the pipeline. A semantic segmentation based on PointNet++ was used to detect and localise the stemwork points. To improve the quality of the segmented stemwork point clouds, a density-based refining pipeline is proposed containing three main processes: non-replacement resampling, interference branch removal, and noise removal. A Tree Quantitative Structural Modeling (TreeQSM) algorithm was then applied to the stemwork point cloud to construct a digital reconstruction. The target phenotypic traits were finally calculated from the digital model by employing an internode association process. The proposed phenotyping pipeline was evaluated with a test dataset containing three tomato plant cultivars: Merlice, Brioso, and Gardener Delight. The related rooted mean squared errors of calculated internode length, internode diameters, leaf branching angle, leaf phyllotactic angle, and stem length range from 4.8 to 64.4%. Considering the time consuming manual phenotyping process, the proposed work provides a feasible solution towards the high throughput plant phenotyping, from which facilitates the related research on plant breeding and crop management.

Mechanisms of mixed slurry flow of deep-sea hydrate exploitation

Marine gas hydrate test production faces several challenges, including low hydrate yield, severe sand sedimentation under jet-breaking conditions, and minimal or even absent fluid returns. To address these challenges and enhance gas hydrate production while maximizing the value of extraction equipment, a layered control engineering strategy is proposed. This strategy is based on the integrated vertical development approach encompassing natural gas hydrates, shallow gas, and natural gas reservoirs. Using a gas-liquid two-phase flow theory and considering both the self-dissociation behavior of hydrates and the effective transport conditions of solid-phase particles, a mathematical model for slurry lifting across different extraction stages was established. The model was solved and validated, ultimately producing a process flow diagram for natural-assisted lifting of hydrate slurry. During the horizontal drilling phase, effective transport of solid-phase particles can be achieved without additional gas injection when the drilling fluid flow rate exceeds 13 L/s. However, gas injection can be used to further accelerate solid particle transport, with an injection range of 0 to 67 L/s, depending on the drilling fluid input. During the hydrate fracturing and recovery stage, solid particle transport can be effectively maintained without additional gas injection when the fracturing flow rate is between 49 and 55 L/s. Within this range, gas injection can be adjusted from 0 to 129 L/s to meet the requirements of hydrate slurry flow. This research provides a reference for improving gas hydrate extraction yield, accelerating early commercialization of hydrate exploitation, and supporting China's “dual carbon” strategic goals.

PROTÓTIPO DE LUVA ELETRÔNICA PARA AVALIAÇÃO DE COORDENAÇÃO MOTORA FINA EM IDOSOS

According to Meinel (1984), fine motor coordination can be defined as: "a particularly small movement activity that requires the use of minimal force but great precision or speed. Then, in partnership with the Control and Automation Engineering course of the Federal Institute of Rondônia (IFRO), a prototype of electronic glove was developed, associated with gametherapy inspired by the game "Guitar Hero". The prototype consists of: a box of lights (leds), of various colors, that will light up under the command of the physiotherapist and should be reproduced by the patient/ volunteer of the research. The glove achieved its objective of being a didactic resource in the evaluation of fine motor coordination of institutionalized elderly at Lar Leal in Porto Velho. The research was authorized by CEP under opinion number: 7.024.081. The present research seeks to promote the stimulation of fine motor coordination and cognitive in the study population.

Conformation Influences Biological Fates of Peptide-Based Nanofilaments by Modulating Protein Adsorption and Interfilament Entanglement.

Filamentous structures exert biological functions mediated by multivalent interactions with their counterparts in sharp contrast with spherical ones. The physicochemical properties and unique behaviors of nanofilaments that are associated with multivalent interaction with protein are poorly understood. Here, peptide-based nanofilaments containing different homotetrapeptidic inserts are reported and their protein adsorption and biological fates are tested. By altering the homotetrapeptides, different peptidic conformations are imposed within the nanofilaments, which result in notable differences in the density of the intermolecular hydrogen bond, determining the amount of adsorbed proteins. The adsorbed proteins can further induce interfilament entanglement of different degrees and patterns, which influences biodistribution and phagocytosis. The nanofilaments with tetrahydroxyproline segment exhibit diminish interfilament entanglement, phagocytosis, and improve circulation, biodistribution, and antitumor efficacy. These findings can deepen the understanding of nanofilament-protein interactions and filament-filament interactions as in the case of amyloid-β plaque, and facilitate the rational design of nanofilaments through peptide conformation control for chemical engineering and anticancer drug delivery.

Towards backward compatibility of ADRC: revisiting classical state-feedback control with integral compensator

In this paper, the problem of backward compatibility of active disturbance rejection control (ADRC) is investigated. The goal is to contextualize ADRC to deliver its interpretations from the established field of linear control systems. For this study, a control algorithm, denoted here as integral disturbance rejection control (IDRC), is considered that combines classical state-feedback control with an integral compensator. At first, an interpretation of ADRC is involved in terms of existing state-space control approaches. Next, a transition to the frequency domain is performed, which is justified as a significant part of practical control engineering is conducted in that domain. For assumed specific plant structures, both ADRC and IDRC are then holistically compared in terms of transfer function representation and frequency characteristics, as well as steady-state convergence conditions. Such a juxtaposition helps to highlight the similarities and differences of both approaches, whereas the utilized bandwidth parameterization is shown to bring the control system to the same form, thus indicating some interesting practical aspects. Finally, the theoretical results concerning both considered control structures are validated in a set of numerical simulations and experiments conducted on a laboratory hardware testbed.

Dosimetry as a Lagging Indicator of Occupational Exposure to Nitrous Oxide in Pediatric Sedation: A Collaborative Process Improvement Project With Industrial Hygiene.

Nitrous oxide (N2O) is commonly used in pediatric procedural sedation. It is an attractive option to facilitate intravenous line placement, as it does not extend sedation recovery from subsequently administered agents. Although debate exists regarding health consequences of occupational exposure now that scavenging of exhaled gases is common, cooperation of pediatric patients to maximize engineering controls is not guaranteed and can contribute to repeated exposure over the course of a clinician's career. There is no global consensus on personal exposure limits, but the National Institute for Occupational Safety and Health published U.S. guidelines. A dosimetry survey of our sedation team during a short N2O procedure for intravenous line placement exceeded the National Institute for Occupational Safety and Health Recommended Exposure Limit (REL) of 25 parts per million. We designed a process improvement initiative to reduce occupational exposure below the Recommended Exposure Limit on serial surveys. A continuous flow, titratable, full-face mask N2O delivery system with scavenging by a central vacuum connection was used. A retrospective chart review of N2O procedures performed before the initial dosimetry survey revealed practice trends in provider behavior during N2O administration. Initiation of N2O gas flow and maintenance of face mask seal on an uncooperative patient were identified as two sources of variability. Two-handed face-masking technique, initiation of N2O gas flow only after masking, and continued masking for 2 min of exhaled scavenging were standardized and socialized as best practices. Subsequent dosimetry surveys of the sedation team were coordinated by Industrial Hygiene. Pre- and post-intervention phases were 17 months each and included 92 and 201 N2O patients, respectively. Six dosimetry surveys occurred in the post phase. Intravenous line placement was the typical procedure surveyed. Dosimetry results for all team members during surveys 1-4 were below the REL, with 14 of 16 samples falling below the level of quantitation. Elevated dosimetry results in survey 5 prompted reevaluation of work practices and equipment. A loose component on the delivery system was discovered, corrected, and incorporated as a pre-procedure check. With no further changes to work practices, dosimetry results were below the REL for survey 6. We layered work practice changes atop engineering controls to reduce occupational exposure levels for medical team members. We utilized dosimetry as a lagging indicator, prompting frequent reassessments of our equipment and processes that we might not otherwise have performed. Pediatric sedation programs are encouraged to consider whether Industrial Hygiene resources might provide synergy to process improvement efforts with inhalational sedation agents.

Exploring structural and electronic properties of topological insulator/graphene nano-heterostructures

There is great interest in the study of topological insulator-based heterostructures due to expected emerging phenomena. However, a challenge of topological insulator (TI) research is the contribution of bulk conduction to the TI surface states. Both strain engineering and thickness control routes, which have been proposed to compensate for bulk doping, can be accessed through the use of nano-heterostructures consisting of topological insulator nanostructures grown on 2D materials. In this work, we report the synthesis of TI/graphene nano-heterostructures based on Bi2Te3 and Sb2Te3 nanoplatelets (NPs) grown on single-layer graphene. Various techniques were used to characterize this system in terms of morphology, thickness, composition, and crystal quality. We found that most of the obtained NPs are mainly <30 nm thick with thickness-dependent crystal quality, observed by Raman measurements. Thinner NPs (1 or 2 quintuple layers ) tend to replicate the topography of the underlying single-layer graphene, according to roughness analysis. Finally, we show preliminary studies of their band structure obtained by Low Temperature Scanning Tunneling Microscopy, Scanning Tunneling Spectroscopy, and by Density Functional Theory. We observe a highly negative ED value which can be attributed to the presence of defects.

Energy Dissipation Assessment in Flow Downstream of Rectangular Sharp-Crested Weirs

Sharp-crested weirs are commonly used in hydraulic engineering for flow measurement and control. Despite extensive research on sharp-crested weirs, particularly regarding their discharge coefficients, more information is needed via research on their energy dissipation downstream. This study conducted experimental tests to assess the influence of contraction ratio (b/B) of rectangular sharp-crested weirs (RSCWs) on energy dissipation downstream under free flow conditions. Five RSCWs with different b/B equals 6/24, 7/24, 8/24, 9/24, and 10/24 were used. The results showed a consistent decrease in relative energy dissipation (Δ𝐸𝑟) with an increase in the head over the weir. Furthermore, as the discharge per unit width (q) increased, the relative energy dissipation (Δ𝐸𝑟) decreased, indicating more efficient discharge over the weir. A higher b/B further reduces Δ𝐸𝑟, suggesting that wider weirs are more effective in minimizing energy losses. The maximum relative residual energy (E1/E0) and relative energy dissipation (Δ𝐸𝑟) occurred at b/B = 10/24 and 6/24, with values of 0.825 and 0.613, respectively. Additionally, the maximum discharge coefficient (Cd) of RSCWs is found at b/B = 6/24, with an average value of 0.623. The results support the accuracy of the proposed equation with R2 = 0.988, RMSE = 0.0083, and MAPE = 1.43%.

Effect of the Concentration of Bioethanol Mixed with Gasoline on the Energy and Environmental Performance of a Hybrid Vehicle in the Worldwide Harmonized Light Vehicles Test Cycle (WLTC)

Increasing the use of renewable biofuels in internal-combustion-engine (ICE) vehicles is a key strategy for reducing greenhouse gas emissions and conserving fossil fuels. Hybrid vehicles used in urban environments significantly reduce fuel consumption compared to conventional internal-combustion-engine cars. In hybrid vehicles integrating electric propulsion with biofuels offers even more significant potential to lower fuel consumption. One would like to think they should also be less polluted in all cases, but some results show that the opposite is true. This study’s aim was to evaluate a hybrid vehicle’s energy and environmental performance using different gasoline–bioethanol blends. A Worldwide Harmonized Light Vehicles Test Cycle (WLTC) study was conducted on a Toyota Prius II hybrid vehicle to assess changes in energy and environmental performance. During the WLTC test, data were collected from the chassis dynamometer, exhaust gas analyser, fuel consumption meter, and engine control unit (ECU). The collected data were synchronised, and calculations were performed to determine the ICE cycle work, brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), pollutant emissions (CO, HC, and NOx), CO2 mass emissions per cycle, and brake specific pollutant emissions per kilometre. The study shows that the performance of the hybrid vehicle’s ICE is strongly influenced by the utilisation of electrical energy stored in the battery, especially at low and medium speeds. As the bioethanol concentration increases, the engine’s ECU advances the ignition timing based on the knock sensor signal. A comprehensive evaluation using the WLTC indicates that increasing the bioethanol concentration up to 70% improves the energy efficiency of the hybrid vehicle’s internal combustion engine and reduces pollutant and CO2 emissions.

Design Strategy, On-Demand Control, and Biomedical Engineering Applications of Wet Adhesion.

The adhesion of tissues to external devices is fundamental to numerous critical applications in biomedical engineering, including tissue and organ repair, bioelectronic interfaces, adhesive robotics, wearable electronics, biomedical sensing and actuation, as well as medical monitoring, treatment, and healthcare. A key challenge in this context is that tissues are typically situated in aqueous and dynamic environments, which poses a bottleneck to further advancements in these fields. Wet adhesion technology (WAT) presents an effective solution to this issue. In this review, we summarize the three major design strategies and control methods of wet adhesion, comprehensively and systematically introducing the latest applications and advancements of WAT in the field of biomedical engineering. First, single adhesion mechanism under the frameworks of the three design strategies is systematically introduced. Second, control methods for adhesion are comprehensively summarized, including spatiotemporal control, detachment control, and reversible adhesion control. Third, a systematic summary and discussion of the latest applications of WAT in biomedical engineering research and education were presented, with a particular focus on innovative applications such as tissue-electronic interface devices, ingestible devices, end-effector components, in vivo medical microrobots, and medical instruments and equipment. Finally, opportunities and challenges encountered in the design and development of wet adhesives with advanced adhesive performance and application prospects are discussed.

Multi-nozzle thrust matching control of STOVL engine

Abstract A multi-nozzle thrust matching control method is proposed in this paper to provide the thrust vector required of lift-fan type short takeoff and vertical landing (STOVL) aircrafts during hover. Attitude-matched thrust commands for each nozzle of STOVL engine are generated based on a six-degree-of-freedom aircraft model. The thrust controller is divided into two blocks according to the coupling analysis. Based on the combination of linear matrix inequality and differential evolution algorithm, a multi-target controller parameters optimization method is proposed to achieve stable disturbance suppression and fast command tracking. Simulations results show that the proposed command generated model is effective and the decoupling control method can effectively suppress the coupling between the loops and realize the matching control of thrust.

Interface engineering enabling thin lithium metal electrodes down to 0.78 μm for garnet-type solid-state batteries

Controllable engineering of thin lithium (Li) metal is essential for increasing the energy density of solid-state batteries and clarifying the interfacial evolution mechanisms of a lithium metal negative electrode. However, fabricating a thin lithium electrode faces significant challenges due to the fragility and high viscosity of Li metal. Herein, through facile treatment of Ta-doped Li7La3Zr2O12 (LLZTO) with trifluoromethanesulfonic acid, its surface Li2CO3 species is converted into a lithiophilic layer with LiCF3SO3 and LiF components. It enables the thickness control of Li metal negative electrodes, ranging from 0.78 μm to 30 μm. Quasi-solid-state lithium-metal battery with an optimized 7.54 μm-thick lithium metal negative electrode, a commercial LiNi0.83Co0.11Mn0.06O2 positive electrode, and a negative/positive electrode capacity ratio of 1.1 shows a 500 cycles lifespan with a final discharge specific capacity of 99 mAh g−1 at 2.35 mA cm−2 and 25 °C. Through multi-scale characterizations of the thin lithium negative electrode, we clarify the multi-dimensional compositional evolution and failure mechanisms of lithium-deficient and -rich regions (0.78 μm and 7.54 μm), on its surface, inside it, or at the Li/LLZTO interface.

Role of Cybersecurity in Engine Control Systems: Safeguarding the Heart of Modern Trucks

This article outlines the importance of cybersecurity for modern engine control systems. Much emphasis is placed on how fast-paced the technologies in the automotive industry are and the several risks involved with their use. Due to high connectivity and heavy dependency on software, serious vulnerabilities are present in trucks' engine control units (ECUs) that pose a severe threat regarding cybersecurity in the automotive industry. The article discusses how engine control systems have been developing over time, enumerates the most common cyber-attacks they face, and points out the consequences that may influence vehicle safety and performance, as well as environmental compliance. Attention is given to regulatory laws, industry standards, and strategies regarding how to handle these challenges. The article also discusses how artificial intelligence influences ECU security and the challenges and opportunities arising in this fast-changing sector. Overall, the article provides a broad overview of the relationship between cybersecurity and ECUs, underlining the fact that strong security is urgently needed to provide safety, reliability, and trustworthiness to modern vehicles.

TDOF PID Controller for Enhanced Disturbance Rejection with MS-Constraints for Speed Control of Marine Diesel Engine

This study proposes a two-degree-of-freedom PID controller design and tuning method based on a simple pole placement approach to enhance servo and regulatory performance while ensuring the stability of diesel engines. In the modeling of the control target, the actuator is analytically modeled. In contrast, the type of model for the diesel engine is derived analytically, and its parameter estimation uses operational data from naval ships. The proposed controller consists of a PID controller to improve regulatory performance and a set-point filter to enhance servo response. PID controller parameters consist of the parameters of the controlled plant model and a single tuning variable. At the same time, the set-point filter comprises the controller parameters and a single weighting factor. To ensure the robust stability of the controller, the controller parameters are tuned based on the maximum sensitivity. To verify the effectiveness of this study, simulations for the speed control of a diesel engine with inherent nonlinearity were conducted under three scenarios. Performance was quantitatively analyzed using the integral of time-weighted absolute error, 2% settling time, 2% recovery time, specified maximum sensitivity, and maximum peak response value, and was compared with Skogestad’s IMC and Lee’s IMC. Based on evaluation indices, the proposed controller demonstrated superior performance in both servo and regulatory responses compared to the two existing control techniques while ensuring stability.

The Analysis of Applied Innovative Mechatronics Technology in Intelligent Driving - A Case Study of New-Energy Vehicles' Development in Mainland China

Abstract. The interdisciplinary field of mechatronics, which amalgamates elements of mechanical, electrical, computer, and control engineering, has fundamentally transformed the automotive industry. This transformative influence is evident in the development of advanced vehicular functionalities such as Automatic Fuel Filling Systems, Car Attitude Control, Antilock Brake Systems (ABS), and Electronic Stability Programs (ESP), as well as in the advent of vehicles equipped with semi-active suspensions. The integration of mechatronics has not only enhanced vehicle safety, efficiency, and performance but has also positioned itself as a cornerstone for the burgeoning electric vehicle (EV) market, particularly in China. Chinese companies, leveraging extensive smart factory and automation technologies, have consequently secured a dominant stance in the global EV landscape, capturing a staggering 60% market share. This paper explores the multifaceted applications of mechatronics in the automobile industry of industrialized nations, with a special focus on its pivotal role in China's technological ascendancy in automotive manufacturing. Through an exploration of practical applications including IoT integration and collaborative robotics, this study underscores the transformative potential of mechatronics in redefining automotive production and operation, propelling the industry toward unprecedented levels of innovation and efficiency.

Adaptive variable gain linear active disturbance rejection control parameter optimization in magnetic levitation

The magnetic levitation ball system is characterized by strong nonlinearity, multiple disturbances, and intrinsic instability, which has long been a thorny problem in the field of control engineering. The magnetic levitation system can be continuously and stably levitated, even in a complex environment. In this thesis, the model of the magnetic levitation ball system is firstly constructed according to the kinetic theory and simplified according to the actual situation. After that, a linear active disturbance rejection control (LADRC) controller for the magnetic levitation ball system is designed. Considering that there are many parameters in the LADRC controller and it is difficult to obtain the optimal control effect by manual tuning, an adaptive variable gain LADRC algorithm is proposed to optimize the control strategy of LADRC parameters. An adaptive iterative algorithm is used to adaptively adjust the bandwidth of the linear extended state observer (LESO) in LADRC, and the convergence of the algorithm is demonstrated by using the Lyapunov function. To solve the problem that the proportional and differential gains of the LADRC controller can only be adjusted unidirectionally and simultaneously, this paper proposes an error variable gain algorithm. The aim is to realize the non-unidirectional and more detailed adjustment of the controller parameters, and it is rigorously analyzed and demonstrated through simulation and experiment. The results show that the proposed algorithm is better than proportional–integral–derivative (PID), sliding mode control (SMC), and LADRC in terms of dynamic performance, steady-state performance, and anti-interference.

Critical Role of Solenoid Valves in Modern Engine Design

Solenoid valves, which serve as actuators, are vital in engine design because they can precisely control fluid and gas flow within the engine systems. This allows fuel injection, emission controls, and better performance in modern engines. This paper explores the role that a solenoid valve has been playing in engine designs and underlines its importance for fuel efficiency, emission reduction, and reliability of the engine's performance. Keywords—Solenoid valves, Actuators, Engine control, Fuel injection, Emission control, Engine performance, Valve timing, Fluid flow regulation, Engine Braking, Piston cooling Nozzle valve, CAM phaser Control.