Instantaneous Control Research Articles

Novelty in Intelligent Controlled Oscillations in Smart Structures

Structural control techniques can be used to protect engineering structures. By computing instantaneous control forces based on the input from the observed reactions and adhering to a strong control strategy, intelligent control in structural engineering can be achieved. In this study, we employed intelligent piezoelectric patches to reduce vibrations in structures. The actuators and sensors were implemented using piezoelectric patches. We reduced structural oscillations by employing sophisticated intelligent control methods. Examples of such control methods include H-infinity and H2. An advantage of this study is that the results are presented for both static and dynamic loading, as well as for the frequency domain. Oscillation suppression must be achieved over the entire frequency range. In this study, advanced programming was used to solve this problem and complete oscillation suppression was achieved. This study explored in detail the methods and control strategies that can be used to address the problem of oscillations. These techniques have been thoroughly described and analyzed, offering valuable insights into their effective applications. The ability to reduce oscillations has significant implications for applications that extend to various structures and systems such as airplanes, metal bridges, and large metallic structures.

Pilots' Reactions to Different Types of Alerts When Using Head-Up Displays.

INTRODUCTION: The benefits of using head-up displays (HUDs) include reducing head-down time during critical flight phases, enhancing awareness of the external environment, and improving in-flight crew performance. However, the monochromatic nature of HUDs, increased head rotation, and longer gaze movement paths might affect pilots' reactions to different types of alerts.METHODS: Pilot workload and behavior differences were examined between HUD and head-down display (HDD) configurations in three alert scenarios. The study was carried out in an A320 flight simulator and 12 pilots participated.RESULTS: Except for one engine-on-fire scenario, pilot workload when using a HUD was significantly lower than using an HDD. In one engine-on-fire (3.98 s vs. 3.57 s) and one gear-disagree (5.42 s vs. 4.69 s) scenario, pilot response time to alerts using HUD was significantly longer than using an HDD. The angle deviations were significantly smaller when using HUDs in both go-around-under-crosswind (2.67° vs. 3.37°) and one engine-on-fire scenario (1.22° vs. 1.89°).DISCUSSION: The HUD is suitable for a lengthy process of manual flight control inputs, which not only reduces workload but also promotes control accuracy. For tasks that rely on automation, the benefits for workload become less obvious. In addition, head rotation and reorientation of attention adversely affected the response time to non-time-critical warnings and cautions. For instantaneous control with high precision requirements, HUDs did not demonstrate a significant advantage.Zheng Y, Lu Y, Jie Y, Fu S. Pilots' reactions to different types of alerts when using head-up displays. Aerosp Med Hum Perform. 2024; 95(9):688-694.

Real-time control of a soft manipulator based on reduced order extended position-based dynamics

Soft robots are high-dimensional nonlinear systems coupled with both geometric and material nonlinearity. Control of such a system is complex and time-consuming. In this study, a real-time trajectory tracking control framework is established based on the reduced order extended position-based dynamics. In contrast to the common nonlinear model order reduction methods that require to collect a large number of data to create the motion subspace, this article's motion subspace is constructed based on the model configuration and material properties. The linear modes of the model and the related modal derivatives provide the reduced order matrix, which streamlines and increases the efficiency of model construction. Then, coupled with the instantaneous optimal control, a real-time reduced order model-based control framework of soft robots can be constructed. Experiments on trajectory tracking of a soft manipulator are conducted to verify the accuracy and efficiency of the proposed controller. The average error of all experiments is within 1 cm; and the single-step calculation time of the controller is about 0.057 s, which is less than the sampling period 0.1 s.

A novel EMS design framework for SPHTs based on instantaneous layer, driving event layer, and driving cycle layer

To effectively harness the energy-saving potential of series–parallel hybrid transmissions (SPHTs) with multiple gears and modes and to enhance the driving cycle adaptability of the rule-based energy management strategy (RB EMS), this study establishes a novel EMS design framework for SPHTs at three levels: the instantaneous, the driving event, and the driving cycle layers. Firstly, an equivalent fuel factor based on the principles of energy conservation and calorific value measurements is constructed, the energy consumption of different working modes and torque combinations under different instantaneous power units is determined, and the decision conditions of working modes are determined. Secondly, the energy consumption of engine and motor torque combination under constant speed, acceleration and deceleration driving events is compared, and the torque distribution feature of multi-power sources is determined. Thirdly, a driving cycle distribution factor is introduced and calculated using vehicle navigation map information, which can adjust the gear switching condition of parallel driving mode online. Based on above, an RB EMS adjusted with driving cycles (ADC-RB EMS) is proposed. The effectiveness of the proposed strategy is then verified through real-world vehicle tests. The fuel consumption performance of this strategy falls between the RB EMS and the dynamic programming (DP) strategy. According to the fuel consumption results, the RB EMS consumes an additional 0.35 L/100 km of fuel, while the DP strategy saves only 3.66% more energy compared to this strategy. The application potential of driving cycle distribution factor in instantaneous optimal control is tested. Compared with ADC-RB and CD-CS, the fuel saving rate is 1.71% and 5.67% respectively, which proves the energy saving performance of A-ECMS. This study provides a development direction for improving the energy saving effect of the RB EMS.

Additive manufacturing of heterogeneous combinatorial functional surface by plasmonic hierarchical sintering of silicon particles for active manipulation of rheological liquid motion

We present a sustainable and efficient additive manufacturing method of silicon-based heterogeneous combinatorial functional surfaces designed to actively manipulate liquid droplet motion dynamics to address advanced rheological engineering challenges and applications. This additive manufacturing enables the instantaneous formation and control of hierarchical multiscale structures with tunable wettability through instantaneous plasmonic thermophysical sintering between laser and Si particles, eliminating the need for additional masks and subsequent processing steps. Furthermore, this fabrication approach can selectively implement heterogeneous combinatorial functional surfaces in a single domain by reversibly switching extreme wettability modes (e.g., from superhydrophobic to superhydrophilic) upon laser irradiation. Continuous superhydrophilic channels in a superhydrophobic background created by selective laser re-irradiation provide sufficient local attraction to manipulate droplet motion along the channel due to van der Waals forces and Laplace pressure fields generated by the difference in wettability. Active manipulation of droplet dynamic motion, such as trajectory tracking and antigravity self-propulsion, can be realized by simply designing a laser scanning path that determines the geometry of the local channel. The manipulation platform for liquid motion dynamics can be applied to active microfluidic channels with no cavity, without the need for an external power source. This advancement has important implications for broad fluid and rheological engineering applications.

Instantaneous power theory-fuzzy intelligent controller (IPT-FIC) based improved low voltage ride-through strategy for grid connected photovoltaic system

Instantaneous power theory-fuzzy intelligent controller (IPT-FIC) based improved low voltage ride-through strategy for grid connected photovoltaic system

Steering opinion dynamics through control of social networks

In this paper, we propose a novel control approach for opinion dynamics on evolving networks. The controls modify the strength of connections in the network, rather than influencing opinions directly, with the overall goal of steering the population toward a target opinion. This requires that the social network remains sufficiently connected, the population does not break into separate opinion clusters, and that the target opinion remains accessible. We present several approaches to address these challenges, considering questions of controllability, instantaneous control, and optimal control. Each of these approaches provides a different view on the complex relationship between opinion and network dynamics and raises interesting questions for future research.

Non-dominated sorting artificial rabbit multi-objective sizing optimization for a conceptual powertrain of a 6 × 4 battery electric tractor truck

In order to tackle the increasingly severe energy crisis, improving the efficiency of the powertrain system in battery electric vehicles has become an effective approach. Based on a 6 × 4 battery electric tractor truck (BETT), the paper focuses on enhancing the dynamic and economic performance of vehicles through advancements in configuration, control strategies, and parameter design. Firstly, a novel multi-motor torque coupling powertrain system based on the parallel-axle transmission is proposed and modeled. Then, an instantaneous minimum energy consumption control strategy for the economic performance simulation and an instantaneous maximum acceleration control strategy for the dynamic performance simulation are designed. Furthermore, a conventional heuristic single-objective optimization algorithm, artificial rabbit optimization (ARO), is improved into a multi-objectives version, non-dominated sorting artificial rabbit multi-objective optimization (NSARMO), by combining the fast non-dominated sorting (FNS) and modifying the calculation method of the energy factor. Finally, an optimization framework consisting of a control layer, model layer, and optimization layer is established and applied to the parameter optimization of the proposed powertrain system. Simulation results demonstrate that the optimization results of the proposed method are superior to those optimized by commonly used non-dominated sorting genetic algorithm-II (NSGA-II) and NSARMO without the modified energy factor, achieving a better balance between dynamic performance and economic performance. Moreover, the proposed method exhibits demonstrates 40.67% and 24.67% improvement in its ability to search for optimal Pareto solutions compared to NSARMO (-)(- means the calculation method of energy factor is not modified) and NSGA-II. At last, a hardware-in-the-loop (HIL) experiment bench is established, and the experiment results indicate that a scheme optimized by the proposed NSARMO exhibits only an approximate performance in energy consumption in the HIL environment compared to the simulation environment, which signifies the effectiveness of control strategy equipped with the optimization results optimized by the proposed method.

A Novel Modulation Method to Suppress the Current Zero-Crossing Distortion for Vienna Rectifier With Different Control Methods Under Unbalanced Grid

Vienna rectifier is a boost type rectifier with unidirectional energy flow, which is widely used in many applications. Under unbalanced grid, there will be even harmonics in dc-link voltage and odd harmonics in input current if traditional control methods are used. Therefore, two control methods for Vienna rectifier under unbalanced grid are introduced, which are balanced positive-sequence current control (BPSC) and instantaneous active power control (IAPC). The current zero-crossing distortion (CZCD) is an inherent issue for Vienna rectifier due to its special circuit topology. The displacement angle between the input current and the voltage is revealed, which is the essence of CZCD. The issue of CZCD is more complex under unbalanced grid than that under balanced grid, and CZCD cannot be addressed well under existing suppression method. A novel method that can minimize CZCD under unbalanced grid is also proposed. The proposed method works well under both balanced and unbalanced grid. Finally, an experimental platform is built, and the feasibility and superiority of the proposed method is verified by comprehensive experiments.

Transient and Steady‐State Friction in Non‐Isobaric Conditions

AbstractThe frictional properties of faults control the initiation and propagation of earthquakes and the associated hazards. Although the ambient temperature and instantaneous slip velocity controls on friction in isobaric conditions are increasingly well understood, the role of normal stress on steady‐state and transient frictional behaviors remains elusive. The friction coefficient of rocks exhibits a strong dependence on normal stress at typical crustal depths. Furthermore, rapid changes in normal stress cause a direct effect on friction followed by an evolutionary response. Here, we derive a constitutive friction law that consistently explains the yield strength of rocks from atmospheric pressure to gigapascals while capturing the transient behavior following perturbations in normal stress. The model explains the frictional strength of a variety of sedimentary, metamorphic, and igneous rocks and the slip‐dependent response upon normal stress steps of Westerly granite bare contact and synthetic gouges made of quartz and a mixture of quartz and smectite. The nonlinear normal stress dependence of the frictional resistance may originate from the distribution of asperities that control the real area of contact. The direct and transient effects may be important for induced seismicity by hydraulic fracturing or for naturally occurring normal stress perturbations within fault zones in the brittle crust.

Architectural Design of IoT Agricultural System in Indonesia

Indonesia’s agricultural system is gradually transitioning towards a contemporary agricultural system. The agricultural system in Indonesia is characterized by its distinctiveness, encompassing a wide range of commodities and diverse meteorological conditions. Situations of this nature necessitate an automation approach based on the Internet of Things (IoT). We design three primary components in its architectural design: the user control and monitoring module, the sensing module, and the action module. The user control and monitoring module facilitates instantaneous monitoring and control through mobile devices and websites, while securely storing gathered data on remote cloud servers. The sensing module acquires environmental data, including light intensity, temperature, and soil moisture, and subsequently transmits this data to the control system via LoRa technology. The control system analyses this data and provides commands to modules that carry out operations such as irrigation, lighting, and nutrient spraying. LoRa technology is highly suitable for long-range communications with minimal power usage, making it an excellent choice for rural locations with unreliable networks. This architectural design enables independent monitoring and control of environmental factors to guarantee the most favourable conditions for crop development, consequently enhancing agricultural efficiency, productivity, and sustainability.

Overcurrent Limitation in Hydrogen Storage Power Plants (HSPP)

The importance of electrical energy storage (EES) systems has been increasingly recognized for enabling the large-scale integration of intermittent renewable energy sources (RES) into the power grid. Among these systems, the Hydrogen Storage Power Plant (HSPP) stands out as a solution capable of independently managing the supply and storage of electrical energy based on network requirements. Previous investigations have shown that the HSPP operating in grid forming mode (GFM) can provide the required ancillary services in the form of instantaneous, primary and secondary control reserves similar to conventional fossil-fired power plants. However, unlike these traditional synchronous generators, the HSPP consists of power semiconductor devices, resulting in much lower overcurrent tolerance. This paper addresses this challenge by proposing a simple yet robust control technique that regulates the maximum current across the HSPP grid interfacing inverter functioning in GFM. The results demonstrate that the controller can maintain the maximum current magnitude below a threshold of 1.2 pu while ensuring the required reactive current contribution during a three-phase fault.

An Instantaneous Load-Sharing Parallel Control Method Using Improved PWM-Capture With DMA in a Power Conversion System

An Instantaneous Load-Sharing Parallel Control Method Using Improved PWM-Capture With DMA in a Power Conversion System

Distributed Resource Allocation and Flow Control Algorithms for mmWave IAB Networks

This paper presents a new distributed slot reservation frame-work for joint resource allocation and flow control in mmWave IAB networks. We derive the Dynamic Slot Reservation (DSR) algorithm from a novel approach to solve a minimum clearing time linear program in a completely distributed manner. The algorithm to solve this problem, the Static Slot Reservation (SSR) algorithm, is also a contribution of the paper. We compare the delay performance of the DSR algorithm with a well known optimal, centralized algorithm, the joint-MWM algorithm, for a realistic IAB network scenario of multi-hop flows. We show that flows that traverse several links have significantly lower delays under DSR than under the joint-MWM algorithm. This paper also provides an instantaneous rate control policy for IAB networks which changes flow rates based on the number of flows at each node in the network. The flow rates under this policy are the same as the steady-state flow rates achieved by the DSR algorithm. We prove that the proposed flow control policy provides stability for all flow arrival rate vectors that are achievable by any flow control policy. This paper provides distributed admission control policies to provide rate and/or latency guarantees to flows under dynamic scenarios with stochastic flow arrivals and changing access link rates.

A Generic Multi-Frequency Repetitive Control Scheme for Power Converters

A Generic Multi-Frequency Repetitive Control (GMFRC) scheme, is proposed to perfectly compensate for all kinds of periodic signals including multi-frequency signals, where multiple selective harmonic repetitive controllers in parallel are added into a stable instantaneous feedback control loop to achieve overall satisfactory performance. The GMFRC scheme provides a general framework for housing various repetitive control and even resonant control schemes in power electronic conversion and other extensive engineering applications. A universal approach to the analysis and synthesis of the digital GMFRC scheme has been developed, which includes the stability criteria and control gain rules. More important, the digital GMFRC controller is transformed into a general fractional-order one for exact compensation of multi-frequency signals and other fractional-order periodic signals in practice. An application example of a 5kVA three-phase PWM inverter under a fractional-order GMFRC scheme is provided. Experimental results demonstrated that the proposed GMFRC scheme can force the inverter to produce required mono-frequency or multi-frequency voltages with high accuracy, fast response and good robustness.

Modified instantaneous power theory control of dynamic voltage restorer powered by photovoltaic system

<span lang="EN-US">Power quality issues have become widespread due to nonlinear electronic converters and loads. Nonlinear components in the power system hamper the power quality, network efficiency and voltage regulation. The power quality issues like sag, swell, and voltage unbalance can be reduced by employing a dynamic voltage restorer (DVR). DVR provides the compensating power from a DC source to minimize the effect of sag, swell, and voltage unbalance. This article presents a power system with DVR using a photovoltaic system (PV) as a DC source instead of a conventional battery source. This article proposes a modified instantaneous power (PQ) control technique to generate the reference signal of load voltage to assure the DVR's superior performance. This modified technique uses an anti-aliasing filter to generate a reference signal. This proposed technique is tested under extreme power quality issues of 80% sag, 20% sag, 120% swell, 170% swell, and voltage unbalance. The DVR is modeled and simulated using MATLAB/Simulink. A comparison is made between the traditional and modified PQ methods from the obtained results. The analyzed results under severe power quality issues suggest that the proposed P-Q control technique is a preferable option for the DVR with PV as a DC power supply.</span>

Design and PIL implementation of a new robust backstepping based low-complexity voltage-oriented control method for four-leg rectifiers

This paper proposes a low computational complexity enhanced voltage-oriented control strategy (EVOC) based on robust backstepping controllers (BSC) in the synchronous rotating frame (dq0 frame) for a PWM four-leg voltage-source-rectifier (FLVSR). Unlike traditional VOC strategies, the suggested EVOC approach does not need any synchronization method and Park transformations, and it has the similar architecture and same features as the traditional VOC when it’s synchronization loop for grid voltage phase angle detection is properly operated. In addition to controlling the FLVSR, the suggested EVOC strategy is also used to develop the model of the three phase FLVSR in the dq0 frame using the concepts of direct instantaneous power control (DPC) theory, which combine the benefits of traditional DPC and traditional VOC with less computational complexity. The robust BSC is adopted for accurate regulation of FLVSR input currents and dc bus voltage simultaneously while taking into account the FLVSR parameter uncertainties. It produces sinusoidal currents with lower ripples and has high robustness against parametric variations. It is also simple to implement and has a relatively high grid voltage disturbance rejection ability. Finally, comparisons with both the traditional VOC strategy using PI controllers (VOC-PIC) and the EVOC strategy using PI controllers (EVOC-PIC) under various conditions demonstrate the superiority and benefits of the proposed EVOC-BSC strategy.

Passive Flow Control for Centrifugal Compressors with Bents Intake Manifold

Centrifugal compressors installations often require bents conduits at the intake due to space constraints. The intake bent manifold creates flow distortion affecting unfavorably the global performance of the compressor. The degradation caused by the inadequate inlet conditions due to turbulence and inlet flow disturbance, which negatively affects the flowing fluid through the curved intake manifold. Hence, significant distortions, within presence of single or twin core vortices whirling off center of the impeller intake alter flow incidence angle and consequently the impeller circumferential energy. Furthermore, inadequate bends configurations generate higher incidence angles, which lead to boundary layer separation and stalling. This paper deals with a 3D numerical investigations of dual bends located upstream of the centrifugal compressor. Several bend setting positions at the compressor intake describing various sequences of intake piping are considered. As first results, specific positions of dual bends are identified for fewer flow disturbance at the impeller eye and stable outflow controlling the incidence angel in a passive mode. it is less cumbersome and cost effective compared to additional devices. For practical industrial prediction, this investigation contribute also toward a mathematical correlation to check the adequacy of intermediate manifold configuration in order to predict the corresponding incidence angle at the impeller intake of the centrifugal compressor for enhanced performance and instantaneous control.

Safe Feedback Motion Planning in Unknown Environments: An Instantaneous Local Control Barrier Function Approach

Mobile robots are desired with resilience to safely interact with prior-unknown environments and finally accomplish given tasks. This paper utilizes instantaneous local sensory data to stimulate the safe feedback motion planning (SFMP) strategy with adaptability to diverse prior-unknown environments without building a global map. This is achieved by the numerical optimization with the constraints, referred to as instantaneous local control barrier functions (IL-CBFs) and goal-driven control Lyapunov functions (GD-CLFs), learned from perceptional signals. In particular, the IL-CBFs reflecting potential collisions and GD-CLFs encoding incrementally discovered subgoals are first online learned from local perceptual data. Then, the learned IL-CBFs are united with GD-CLFs in the context of quadratic programming (QP) to generate the safe feedback motion planning strategy. Rather importantly, an optimization over the admissible control space of IL-CBFs is conducted to enhance the solution feasibility of QP. The SFMP strategy is developed with theoretically guaranteed collision avoidance and convergence to destinations. Numerical simulations are conducted to reveal the effectiveness of the proposed SFMP strategy that drives mobile robots to safely reach the destination incrementally in diverse prior-unknown environments.

Power quality improvement in distributed generation system using intelligent control methods

Hybrid <span>electric power generation and its integration with the grid to supply consumer demand is main focus of this paper. The use of nonlinear load and advanced power electronic equipment-based devices at the consumer end introduces power quality issues in the power system network in terms of voltage and current. This paper explains the design of a control algorithm for a unified power quality conditioner used for mitigating both voltage and current-based power quality issues. The dynamic voltage restorer of unified power quality controller (UPQC) is designed with a unit vector control algorithm and the distribution static synchronous compensator (DSTATCOM) is designed with fuzzy logic and adaptive network-based fuzzy inference system based instantaneous reactive power theory control algorithm. The simulation model built using the MATLAB platform includes a three-phase voltage source along with hybrid electric power generation connected to linear and non-linear loads operating under different conditions. The result is analyzed in terms of voltage and current total harmonic distortion compared with IEEE 512 power quality standards and power factor improvement. The paper shows the adaptive neuro-fuzzy inference systems (ANFIS)-based control algorithm gives better results in terms of total harmonic distortion (THD) compared to the fuzzy-based control algorithm. The power factor is improved using ANFIS-based controller proving the efficiency of the controller</span>.