Structure Control Method Research Articles

Research of Grasping Strategy of Bionic Manipulator

This article reviews the research progress of bionic manipulator grabbing strategies in recent years, subsequently, the classification of existing bionic manipulator grabbing strategies was sorted out in detail, including crawling strategies based on the principle of biological inspiration, crawling strategies based on mechanical models and crawling strategies based on intelligent algorithms. First, the paper outlines the structural design and control methods of bionic manipulators. Next, the classification and characteristics of existing crawling strategies are summarized. These include strategies based on biological mechanisms, those guided by intelligent optimization algorithms, and data-driven learning methods. On this basis, the advantages and disadvantages of various crawling strategies and their performance in practical applications are compared and analyzed. Finally, the paper discusses the flexibility of bionic manipulator grabbing strategies, challenges and future development trends in adaptability and intelligence. This review not only provides a comprehensive theoretical reference for researchers in the field of bionic manipulator grasping strategies but also identifies key areas for future technological development.

Research on Structural Optimization and Excitation Control Method Using a Two-Dimensional OWPT System for Capsule Robots Based on Non-Equivalent Coils.

The rapid development of wireless power transfer (WPT) technology has provided new avenues for supplying continuous and stable power to capsule robots. In this article, we propose a two-dimensional omnidirectional wireless power transfer (OWPT) system, which enables power to be transmitted effectively in multiple spatial directions. This system features a three-dimensional transmitting structure with a Helmholtz coil and saddle coil pairs, combined with a one-dimensional receiving structure. This design provides sufficient internal space, accommodating patients of various body types. Based on the magnetic field calculation and finite element analysis, the saddle coil structure is optimized to enhance magnetic field uniformity; to achieve a two-dimensional rotating magnetic field, a phase difference control method for the excitation signal is developed through the analysis of circuit topology and quantitative synthesis of non-equivalent magnetic field vectors. Finally, an experimental prototype is built, and the experimental results show that the one-dimensional transmitting coil achieves a minimum received voltage stability of 94.5% across different positions. When the three-dimensional transmitting coils operate together, a two-dimensional rotating magnetic field in the plane is achieved at the origin, providing a minimum received power of 550 mW with a voltage fluctuation rate of 7.68%.

Collaborative Construction Method of Biomedical Knowledge Graph Based on Multi-Blockchain

The collaborative construction method of knowledge graph based on blockchain is crucial for the safe and efficient construction of biomedical knowledge graph (BioKG), and has received widespread attention from the academic and medical circles. At present, the data sources of BioKG are very wide. While using multi-source data to collaboratively build a knowledge graph, data redundancy problems often occur. Once data from a large number of sources is available, it becomes difficult for the system to ensure data consistency in a reliable way. In addition, the increase in inconsistent and redundant data also reduces the efficiency of collaboration in the system. The traditional blockchain-based collaborative construction method of BioKG is difficult to effectively solve these problems. Multi-blockchain technology provides a new solution for the construction of collaborative knowledge graphs in the biomedical field, which is characterized by good scalability and diversified applications. To this end, we propose a multi-person collaboration construction method for BioKG based on multi-blockchain, named collaborative construction method chain (CCMC). CCMC uses the multi-chain structure and clock cycle control method of the blockchain to separate user operations and system verification, and uses the read-write separation function to improve the consistency of the collaborative version. In addition, we propose a semantic fusion method that effectively reduces data redundancy in the collaborative process and improves the efficiency of BioKG collaborative construction. Performance testing and comparative evaluation confirmed that compared with previous methods, CCMC significantly improves the creation of collaborative knowledge graphs and meets the requirements of multi-person collaborative construction.

A simple and effective strategy for W[sbnd]Cu functionally graded materials with continuous gradient

Functionally graded materials (FGM) have great potential in various applications, but require reliable and efficient manufacturing techniques. This study proposes a preparation strategy for WCu FGM with continuous gradient structure. The W green bodies with a continuously varying W content were prepared by using a self-designed mold to control compression deformation. Subsequently, two types of WCu FGM samples were successfully fabricated through pre-sintering and infiltration processes. The W contents ranged from 64.8 wt% to 81.1 wt% and 75.3 wt% to 90.5 wt% respectively. The microstructure, density, Vickers hardness and electrical conductivity exhibited a continuous trend of change with the variation of W content. This gradient structure control method facilitated the efficient preparation of WCu FGMs with continuously varying compositions. Moreover, it could be extended to achieve the continuous variation of composition and properties in other materials prepared via infiltration techniques.

Review Paper on Seismic Analysis of Multi-Storied Reinforced Concrete Building with Fluid Viscous Dampers

Abstract: Frequent earthquakes around the world and the large number of buildings at risk have made it essential to focus on controlling how structures respond to these events. This demand has driven the increased use of structural response control methods globally. This study investigates the seismic performance of multi-storied Reinforced Concrete (RC) Buildings, distinguishing between Regular and Irregular Plan , with a focus on the role of Fluid Viscous Dampers (FVDs). The study aims to quantify the improvements in seismic resilience provided by these damping devices in mitigating the adverse effects of seismic events. Buildings having Regular and Irregular Plans are analyzed, with and without FVD using ETABS2018. The story responses in terms of Pseudo Spectral Accelerations, Maximum Displacement, Story Drift and Story Shear have been compared. The results of the Time History Analysis represent the effectiveness of dampers in improving the structural response and the damping demand on structural systems

Designs in Bionic Robots: Compared with Conventional Robots

With the advancement in relative technology, robotics is gaining an increasing amount of attention among engineers and researchers as it is a current focus on enabling peoples lives to become more convenient. However, there is another type of robot designed very differently from functional robots like delivery robots and quadrotors that most people are familiar with, bionic robots. This is a kind of robots that gets design inspiration from real animals in nature, from the design of structure to altitudes and mechanisms of motion. How bionic robots are designed, and how the conceptional difference of bionic robots with other robots is reflected on their physical designs are the focuses of this paper. In this paper, four basic types of bionic robots are introduced and 17 existing designs of bio-inspired vehicles are included. 10 bionic aerial vehicles in 3 smaller classifications are compared to 3 conventional aerial vehicles in order to figure out differences in 3 aspects (structure design, sensors, and control method). The results show that bionic robots usually have more degrees of freedom in order to mimic animals attitudes, and are lighter in weight. Typically, bio-inspired aerial vehicles employ different wing systems compared with conventional ones. Additionally, while conventional vehicles favour PID more because of its ease of construction, bionic robots use machine learning techniques. Both types of robots use the same sensors, which is necessary for them to detect their environment. However, their control methods differ due to different purposes.

Main cable structure analysis and construction control of short span suspension bridge within three-tower

The Feng Chu suspension bridge in Xiangyang holds the distinction of having one of the shortest span lengths among global suspension bridges, measuring less than half the length of conventional designs. This paper focuses on the engineering background of the bridge and delves into the analysis of the main cable structure and construction control methods for short-span suspension bridges with three towers. The study examines the impact of elastic modulus deviation in the main cable and the dead-load error of the stiffening beam on key parameters such as the unstressed length of the main cable, pre-deflection of the cable saddle, and mid-span elevation of the empty cable. Additionally, the effects of temperature, span, and cable length on the sag of the empty cable during the erection process are analyzed. Findings reveal that the elastic modulus and dead-load error significantly influence the unstressed length of the main cable, pre-deflection of the saddle, and the shape of the empty cable. This study establishes a relationship between changes in cable length and mid-span sag, providing valuable theoretical guidance for aligning and adjusting the main cable strands. Furthermore, synchronized alignment adjustments for the two mid-span sections are proposed to prevent main cable strand sliding, which may occur due to significant differences in sag between the sections.

Research on active-passive integrated vibration isolator based on metal rubber and piezoelectric actuator

Abstract The paper introduces a novel active-passive integrated vibration isolator based on metal rubber and piezoelectric actuator, along with an adaptive active vibration control strategy. The active control strategy employs the adaptive dynamic step filtered-x normalized least mean squares algorithm, allowing the step size to adaptively adjust with the error. The secondary control path of the algorithm is modeled using the enhanced rate-dependent Prandtl–Ishlinskii model and the auto-regressive with extra inputs model. The active-passive integrated vibration isolator achieves broadband vibration isolation from 10 to 200 Hz. Compared to passive isolation, the transmissibility decreases from 0.99 to 0.056 at 10 Hz, from 3.02 to 0.068 at the resonance frequency, and from 0.057 to 0.046 at 200 Hz. This study provides a theoretical and experimental foundation for the design of a novel, broadband, and efficient active-passive integrated vibration isolator structure and active control method.

Design and Motion Control of Master-Slave Control Endotracheal Intubation Robot.

Master-slave remote control technology allows patients to be treated promptly during transport and also reduces the risk of contagious infections. Endotracheal intubation, guided by endoscopy and a master-slave system, enables doctors to perform the procedure efficiently and accurately. In this paper, we present the development of a master-slave controlled endotracheal intubation robot (EIR). It is based on operation incremental mapping, a weighted recursive average filtering method to reduce vibration, and a virtual fixture designed to reduce mishandling in minimally invasive surgery. Simulation analysis of the master-slave control demonstrates that the weighted recursive average filtering method effectively reduces vibration, while the virtual fixture assists in confining the operator's movement within a delimited area. Experimental validation confirms the validity of the robot's structural design and control method. The developed robot successfully achieves the necessary motion for endotracheal intubation surgery through master-slave control.

Advanced Control Solutions for DFIG Wind Turbines: From Vector to Predictive Control

This paper investigates advanced control strategies for a doubly-fed induction generator-based wind turbine (DFIG-WT), focusing on vector control and model predictive control (MPC). Initially, it introduces the DFIG-WT structure and general control methods, then explores vector control for effective decoupled power management of active and reactive power. Despite vector control's efficiency, its limitations in handling constraints are highlighted, leading to the adoption of MPC. The study examines MPC's application in current control for three-phase two-level converters, showing its capability for fast tracking and response. Further, it explores MPC's model predictive torque control, demonstrating its proficiency in handling various requirements through a well-designed cost function. Overall, this research emphasizes MPC's adaptability and efficiency in optimizing DFIG-WT performance under varying operational conditions.

Controlling TPMS lattice deformation for enhanced convective heat transfer: A comparative study of Diamond and Gyroid structures

This study investigates the enhancement of convective heat transfer in Triply Periodic Minimal Surfaces (TPMS), focusing on Gyroid and Diamond lattice structures. An innovative lattice structure control method, employing a Deform-Control parameter (β), is proposed to modulate lattice deformation within their mathematical frameworks. Numerical simulations validated by experimental measurements were conducted to analyze the impact of varying β values from 0 to 0.75 on the thermo-hydraulic performance of both lattice types at flow rates ranging from 0.4 m3/h to 2 m3/h. The results indicate significant improvements in heat transfer efficiency with increasing β. For Gyroid structures, increasing β from 0.1 to 0.75 led to a 3.8% to 32.7% rise in convective heat transfer coefficients and a 3.2% to 23.7% increase in Nusselt numbers. Diamond structures also demonstrated enhancements, with coefficients and Nusselt numbers climbing by 2.9% to 10.4% and 3% to 7%, respectively. Notably, both Gyroid and Diamond structures showed increase in flow resistance at higher β values, highlighting a critical balance between heat transfer efficiency and fluid flow considerations. This research presents a promising control method for optimizing heat transfer in TPMS structures, offering opportunities for more efficient and effective heat dissipation solutions.

Gradient‐Strained Van Der Waals Heterojunctions for High‐Efficient Photodetectors

AbstractMaximizing light‐to‐electricity conversion efficiency is a crucial challenge for the practical applications of 2D material photodetectors. However, due to the lack of stable and precise electronic structure control methods for 2D materials, the driving force of photogenerated carriers is insufficient that severely hinders the efficiency of separation and transport. Herein, a gradient‐modulated, stable and precise strain applied strategy for 2D materials is designed and constructed, which results in a significant improvement in the detect efficiency of ZnO/WSe2/graphene van der Waals heterojunction photodetectors. Different from the overall strain of all‐component materials in typical photodetectors, biaxial tensile strain is applied to WSe2 that can be precisely modulated by controlling the height of ZnO nanorods, while the strain is nearly unaffected to ZnO. As the strain modulation increases from 1.3% to 4.0%, the external quantum efficiency (EQE) of the heterojunction increases from 11.4% to 35.3%, representing a threefold increase. Furthermore, with increasing strain, the EQE can reach higher levels. Moreover, the strain‐enhanced conversion efficiency mechanism is elucidated that results from the synergistic effect of the strain‐induced WSe2 exciton convergence and the strain‐increased ZnO/WSe2 interface barrier, which enhances the carrier interface separation efficiency.

Optomagnetic Coordination Helical Robot with Shape Transformation and Multimodal Motion Capabilities.

Soft robots with magnetic responsiveness exhibit diverse motion modes and programmable shape transformations. While the fixed magnetization configuration facilitates coupling control of robot posture and motion, it limits individual posture control to some extent. This poses a challenge in independently controlling the robot's transformation and motion, restricting its versatile applications. This research introduces a multifunctional helical robot responsive to both light and magnetism, segregating posture control from movements. Light fields assist in robot shaping, achieving a 78% maximum diameter shift. Magnetic fields guide helical robots in multimodal motions, encompassing rotation, flipping, rolling, and spinning-induced propulsion. By controlling multimodal locomotion and shape transformation on demand, helical robots gain enhanced flexibility. This innovation allows them to tightly grip and wirelessly transport designated payloads, showcasing potential applications in drug delivery, soft grippers, and chemical reaction platforms. The unique combination of structural design and control methods holds promise for intelligent robots in the future.

Depth control of an unmanned underwater vehicle based on robust inversion and sliding mode variable structure control

This paper addresses the depth control problem of an underactuated Unmanned Underwater Vehicle (UUV) subject to model uncertainties and ocean current interference. A robust inversion sliding mode variable structure control method is proposed. First, a vertical-plane UUV depth control model is established. Then, the inversion control method is combined with the sliding mode variable structure control method to devise an inversion sliding mode control algorithm. In order to further improve the control system’s robustness against external environmental interference, a robust control methodology is introduced for the design of the depth controller. Simulation results demonstrate that the designed controller effectively addresses the issues of model uncertainties and ocean current interference, thereby enhancing the UUV’s depth control accuracy.

Using real-time hybrid simulation for active mass damper experimentation and validation

This paper proposes a novel real-time hybrid simulation (RTHS) method for advancing active mass driver (AMD) control techniques. A comprehensive derivation of the equations of motion are developed, where the tracking problem of absolute acceleration is addressed by transforming it into a displacement tracking problem, within the RTHS control loop. The simulated and experimental results demonstrate acceptable acceleration tracking using this methodology, enabling a seamless and effective option for controlling the shake table transfer system, within the RTHS framework. To demonstrate and validate the effectiveness of the proposed techniques, complete AMD shake table, and AMD-RTHS experiments are conducted. To address the effects of uncertainty, a series of tests are conducted to form an uncertainty response envelope. Comparisons between RTHS and shake table tests show that the responses lie within RTHS uncertainty regions, demonstrating that acceleration can be successfully tracked. This study shows that an AMD control experiment can be realized using RTHS techniques, thus offering an option to advance the development of AMD control techniques. Finally, an RTHS framework is proposed for performance evaluation of structural control methods using AMDs.

Design of ABS sliding mode control system for in-wheel motor vehicle based on road recognition

Aiming at the problem that the current ABS control algorithm cann’t make full use of the ground braking force to complete the braking when the complex road surface is in emergency braking, the ABS sliding mode variable structure control method based on road surface identification is proposed. Combined with the in-wheel motor of in-wheel motor electric vehicle, a coordinated control method of motor hydraulic composite is designed. Based on the fuzzy logic control method, the road adhesion coefficient is estimated to realize the identification of typical roads and dynamically obtain the optimal slip rate of different roads. The ABS sliding mode variable structure controller is designed with the optimal slip ratio and the actual slip ratio as input, and the saturation function is used to replace the sign function in the traditional sliding mode variable structure control to weaken the ’ chattering ’ phenomenon in the sliding mode variable structure control, and then the ABS controller is designed. Taking the experimental prototype vehicle driven by four-wheel hub motor as the research object, an eight-degree-of-freedom dynamic simulation model of the whole vehicle is established. Compared with the traditional PID controller, the braking time is shortened by 0.2 s and the braking distance is shortened by 2.3 m, which shows the feasibility of the designed controller. Through the simulation braking experiment of the docking road, the adaptability and real-time performance of the ABS sliding mode controller are verified, and the importance of the road adhesion coefficient identification to the ABS controller is verified.

Design of ABS fuzzy sliding mode control system based on pavement recognition

A fuzzy sliding mode variable structure control method based on road surface recognition was proposed to solve the problem that the Anti-lock Braking System (ABS) effect of current ABS algorithm was not ideal on complex road surface. In the road recognition module, real-time estimation of five typical road surfaces using fuzzy logic control. Dynamic calculation of optimal slip ratio for different road surfaces based on identified road conditions. Design of ABS sliding mode variable structure controller with optimal slip ratio and actual slip ratio as input. Aiming at the chattering problem of sliding mode control, a fuzzy controller is designed to reduce chattering. An 8-DOF dynamic simulation model of a four-wheel hub motor is established. The effectiveness of the controller is verified by braking simulation experiments on medium and low adhesion road. By comparing the simulation test with the traditional sliding mode controller under the condition of high adhesion road, the suppression effect of the system chattering is verified, and its excellent control performance is proved.

A novel convective heat transfer enhancement method based on precise control of Gyroid-type TPMS lattice structure

Innovative single-phase flow heat transfer enhancement technologies can improve heat dissipation efficiency and reduce the weight and volume of heat dissipation equipment. Triply Periodic Minimal Surfaces (TPMS) hold promise as a outstanding single-phase heat transfer enhancement structure. To further improve the convective heat transfer performance of TPMS, this study independently presents a novel lattice structure control method specifically designed for Gyroid-type TPMS, along with the corresponding mathematical equation. By adjusting the parameter “α” in the equation, the Gyroid lattice geometry can be controlled. This study named “α” as the “Lattice deformation control parameter of Gyroid”. Numerical simulations indicate that increasing α from 0 to 0.25 within the Reynolds number range of 282–2579 can lead to a 19.9–28.9% increase in the average convective heat transfer coefficient (h¯) of the Gyroid, a 0.3%-4.5% increase in the Nusselt number (Nu), and a 13.0%-20.3% decrease in the average friction factor (f¯). The research results suggest that optimizing α is a promising new technology for enhancing convective heat transfer of Gyroid-type TPMS, as it not only improves its heat transfer performance but also reduces its flow resistance. The main reason for the convective heat transfer enhancement of Gyroid-type TPMS with increasing α is the increase in the heat transfer area, while the reduction of flow resistance is mainly due to the formation of the “flow-guiding structure” inside the Gyroid.

Self-Organizing Interval Type-2 Fuzzy Neural Network Compensation Control Based on Real-Time Data Information Entropy and Its Application in n-DOF Manipulator.

In order to solve the high-precision motion control problem of the n-degree-of-freedom (n-DOF) manipulator driven by large amount of real-time data, a motion control algorithm based on self-organizing interval type-2 fuzzy neural network error compensation (SOT2-FNNEC) is proposed. The proposed control framework can effectively suppress various types of interference such as base jitter, signal interference, time delay, etc., during the movement of the manipulator. The fuzzy neural network structure and self-organization method are used to realize the online self-organization of fuzzy rules based on control data. The stability of the closed-loop control systems are proved by Lyapunov stability theory. Simulations show that the algorithm is superior to a self-organizing fuzzy error compensation network and conventional sliding mode variable structure control methods in control performance.

Investigation of vibration performance of pure active single and multi-feedback controls for a tall RC building

Structural control methods are applied to eliminate the structural damages caused by the vibrations in the buildings and to improve their dynamic behavior of them under dynamic lateral loads. In this paper, the pure active control performance of a tall building under the influence of earthquake records, in which the effective time duration is determined by considering the ARIAS energy distribution, is presented. The building's pure active control performance in the period when the earthquake records have the maximum effect on the structure is examined. Eleven earthquake records are selected to better evaluate the effect of vibration control performance. A genetic algorithm is used to determine the parameters of single and multi-feedback controllers, and its effect on the vibration eliminations at the top and all floors is studied. Also, the effect of displacement and velocity feedback on seismic vibration control is evaluated. To carry out the vibration control studies of the building, the mathematical model is extracted from the finite element model created in ANSYS and verified with finite element analysis. It is observed that the displacement value at a reference location on the building is reduced from 0.735 m to 0.019 m, 0.004 m, and 0.002 m, respectively, by the Proportional-Integral-Derivative, Direct Velocity Feedback, and Optimal controllers. The results show that the multi-feedback control is more effective than the single-feedback control application in reducing the vibration amplitudes at all floors in the pure active control system.