Intensive Control Research Articles

Analysis and design of wire winding tension control system based on genetic algorithm and fuzzy PID

Wire winding is a key process in transformer manufacturing, and the accuracy of tension control directly affects the quality of the products. To achieve the requirement of constant tension winding of wire, the influence of roll diameter, speed, and other factors on the dynamic performance of tension is analyzed by establishing the dynamic model of unwinding and winding as well as the pendulum part. A control strategy combining proportional-integral-derivative (PID) control with fuzzy control is adopted, and the parameters of the fuzzy PID controller are optimized using an improved genetic algorithm. Simulation results demonstrate that the optimized fuzzy PID controller significantly reduces tension overshoot and effectively suppresses the tension fluctuation when the speed and roll diameter change, and the tension fluctuation is controlled within 2%. Finally, the feasibility of the optimized fuzzy PID controller in the tension control system is experimentally validated.

Design of a tooth-shaped magnetorheological brake with multiple coils

This research presents an optimized design for a tooth-shaped magnetorheological brake (MRB) with multiple coils. The MRB configuration consists of a disk immersed in magnetorheological fluid (MRF), where four coils act as electromagnets when an electric current is applied. The energized coils induce the alignment of suspended particles in the MRF, forming a chain-like structure that increases the fluid's viscosity. This rapid, strong, and controllable phenomenon enables the MRB to find applications in haptic systems, tension control, and industrial braking systems. To analyze the electromagnetic behavior of the brake, Finite Element Method (FEM) simulations are conducted using ANSYS APDL, and the optimization process is performed utilizing ANSYS Workbench software. The software provides optimized geometries for the brake, resulting in significant improvements in desired performance aspects compared to prior designs, etc.

Programmable Lipid Bilayer Tension-Control Apparatus for Quantitative Mechanobiology.

The biological membrane is not just a platform for information processing but also a field of mechanics. The lipid bilayer that constitutes the membrane is an elastic body, generating stress upon deformation, while the membrane protein embedded therein deforms the bilayer through structural changes. Among membrane-protein interplays, various channel species act as tension-current converters for signal transduction, serving as elementary processes in mechanobiology. However, in situ studies in chaotically complex cell membranes are challenging, and characterizing the tension dependency of mechanosensitive channels remains semiquantitative owing to technical limitations. Here, we developed a programmable membrane tension-control apparatus on a lipid bilayer system. This synthetic membrane system [contact bubble bilayer (CBB)] uses pressure to drive bilayer tension changes via the Young-Laplace principle, whereas absolute bilayer tension is monitored in real-time through image analysis of the bubble geometry via the Young principle. Consequently, the mechanical nature of the system permits the implementation of closed-loop feedback control of bilayer tension (tension-clamp CBB), maintaining a constant tension for minutes and allowing stepwise tension changes within a hundred milliseconds in the tension range of 0.8 to 15 mN·m-1. We verified the system performance by examining the single-channel behavior of tension-dependent KcsA and TREK-1 potassium channels under scheduled tension time courses prescribed via visual interfaces. The result revealed steady-state activity and dynamic responses to the step tension changes, which are essential to the biophysical characterization of the channels. The apparatus explores a frontier for quantitative mechanobiology studies and promotes the development of a tension-operating experimental robot.

Ca2+-dependent vesicular and non-vesicular lipid transfer controls hypoosmotic plasma membrane expansion.

Robust coordination of surface and volume changes is critical for cell integrity. Few studies have elucidated the plasma membrane (PM) remodeling events during cell surface and volume alteration, especially regarding PM sensing and its subsequent rearrangements. Here, using fission yeast protoplasts, we reveal a Ca2+-dependent mechanism for membrane addition that ensures PM integrity and allows its expansion during acute hypoosmotic cell swelling. We show that MscS-like mechanosensitive channels activated by PM tension control extracellular Ca2+ influx, which triggers direct lipid transfer at endoplasmic reticulum (ER)-PM contact sites by conserved extended-synaptotagmins and accelerates exocytosis, enabling PM expansion necessary for osmotic equilibrium. Defects in any of these key events result in rapid protoplast rupture upon severe hypotonic shock. Our numerical simulations of hypoosmotic expansion further propose a cellular strategy that combines instantaneous non-vesicular lipid transfer with bulk exocytic membrane delivery to maintain PM integrity for dramatic cell surface/volume adaptation.

Research on constant tension yarn transfer control technology based on AGA-PID and FOC algorithm

To solve the problems of poor real-time tension tracking, large overshoot, long adjustment time, and large tension fluctuation error that exist in the current control system for yarn feeding in the circular weft knitting machine, this paper presents an optimized and improved adaptive genetic algorithm (AGA) for adjusting the PID (Proportional Integral Derivative) parameters of the tension control part of the yarn-conveying system (AGA-PID). The algorithm is combined with the field-oriented control technology of the permanent magnet synchronous motor to design a closed-loop control strategy for the yarn-conveying system of a circular weft knitting machine. The MATLAB-Simulink simulation model was used to analyze the external tension loop-based AGA-PID controller and permanent magnet synchronous motor dual closed-loop control strategy of the yarn transport control system. The experimental verification was conducted by constructing an experimental platform that simulates the real process of yarn transportation. The outcomes of system simulations and experiments have consistently demonstrated that the AGA-PID control algorithm outperforms the GA-PID and PID control algorithms in terms of overshooting, response speed, stability, and anti-jamming ability. The yarn transport control system, which is designed to operate based on an AGA-PID control algorithm, is capable of reducing the fluctuations in tension that occur during the transportation of yarn and exhibits enhanced control accuracy, effectively stabilizing yarn tension control during the conveying process. The application of this algorithm can enhance the overall elasticity uniformity and surface flatness of knitted fabrics, thereby facilitating the realization of adjustable and controllable local elasticity in fabrics.

Modeling and Verification of Cable-Hole Transmission Tension Ratio Considering the Cable Lateral Extrusion

Cable-hole transmission is widely applied in cable-driven mechanisms to reduce the mechanical size. However, the driving tension is attenuated with the cable threading through the hole caused by uncertain factors such as local deformation, friction, and other effects, and errors in cable-hole transmission occur. To improve the transmission accuracy of cable-driven mechanisms, a tension distribution model considering the cable lateral extrusion is established. Then, an analytical tension ratio of the cable-hole transmission is derived based on the perturbation method and tension distribution model. Parameters of the tension ratio are identified using a particle swarm optimization algorithm. An adaptive tension control method considering the cable lateral extrusion is designed and compared with the method excluding the cable lateral extrusion in the cable-hole transmission. Finally, a cable-hole transmission experimental device was constructed to verify the tension ratio, parameter identification, and servo control method of the cable-hole transmission. The results show the motion control accuracy of the cable-driven mechanism can be significantly improved with the tension ratio considering the cable lateral extrusion. Compared to the case excluding the cable lateral extrusion, the errors in cable-hole transmission considering the lateral extrusion are reduced by an order of magnitude, and the tension vibration is significantly weakened.

A Skin Tension Controller for Chronic Skin Wound Enabled by Flexible Strain Gauges

A Skin Tension Controller for Chronic Skin Wound Enabled by Flexible Strain Gauges

Modeling and control of perturbation torques and mass distribution impact on a tethered system for a 12U CubeSat in sun-synchronous orbit

Tethered CubeSat systems are characterized by momentum exchange and gravity gradient stabilization, and encounter stability challenges, especially with shorter tethers in highly inclined and eccentric orbits. This study investigates the libration dynamics of a 12U CubeSat in its stowed configuration, which separates into two satellites connected via tether, throughout its deployment, station-keeping, and retrieval phases. Two deployed configurations, symmetrical 6U-6U, and asymmetrical 8U-4U connected by a non-conductive tether with a maximum length of 100m are analyzed. The study accounts for perturbations including Earth’s oblateness, atmospheric drag, solar radiation pressure, and lunisolar gravitation, modeling the tether as a rigid, extendable rod and the satellites as lumped masses. The translational and rotational dynamics are decoupled, assuming the system’s center of mass follows an unperturbed Keplerian Sun-synchronous orbit at altitudes between 400 and 600km. A tension control strategy based on Lyapunov’s direct method and supplemented by external actuation torques is explored. Results show high orbit eccentricity significantly affects the maximum in-plane libration angle. The 6U-6U system experiences smaller disturbance torques but greater tether tension variations than the 8U-4U system. Both configurations exhibit larger in-plane oscillations compared to near-zero out-of-plane oscillations, nonetheless, eclipse passages exacerbate the out-of-plane libration of the 8U-4U system. Relative stability is maintained during deployment, however, retrieval is chaotic, with notable oscillations in libration angles and tether tension. The tension control strategy effectively dampens oscillations during retrieval but loses effectiveness as tether tension approaches zero at retrieval’s conclusion. External actuation torques, ranging from 1-2mNm for deployment to 15mNm for retrieval, complement tension control.

Research on dynamic modeling and control strategy of four anti-swing cable system for ship-mounted cranes

Ship-mounted cranes are becoming increasingly essential to modern ocean shipping. However, due to the continuous influence of waves, currents, and winds, achieving accurate and fast lifting is difficult because of the large payload swing during the lifting operation. Therefore, this study proposes a Four Anti-swing Cable System (FASCS) for ship-mounted cranes. Firstly, a dynamic model of the FASCS was established by using Robotics and Newton method, and a tension control method (TCM) is designed to reduce the swing angle of the payload. Concurrently, a sliding mode variable structure controller with improved reaching law (SMVSC-IRL) is designed to control the cooperative movement of the anti-swing cables and prevent the occurrence of snap. The dynamic characteristic analysis by MATLAB/Simulink shows that the swing angle suppression effect reaches 89.3% on average, and the projected area of the payload trajectory was reduced by 60%, which can significantly improve the efficiency of ship-mounted cranes lifting operations. In addition, the length and speed of cables in errors can approach 0 within 7 s, and the strong robustness of the designed SMVSC to control the cooperative motion of the anti-swing cables is proved. The results of this study contribute to the in-depth optimization and engineering verification of the FASCS for ship-mounted cranes.

Multi-Span Tension Control for Printing Systems in Gravure Printed Electronic Equipment

Multi-Span Tension Control for Printing Systems in Gravure Printed Electronic Equipment

Laser-assisted thermoplastic composite automated fiber placement robot for bonding GF/PP unidirectional composites and braided composites

Laser-assisted thermoplastic composite automated placement method has been applied to the molding of composites due to its advantages of fast molding speed and high heating efficiency. This study focuses on designing a robot for laser-assisted thermoplastic composite automated fiber placement, employing a modular approach to create a versatile fiber placement head. Control functions, such as electrical circuits, a computer interface, and tension control, were developed. Hybrid laminates, combining GF/PP unidirectional and braided composites, were manufactured by independently adjusting laser power (275 W–400 W) and compression force (150 N–400 N). Bonding properties were analyzed using wedge peel tests and microscopic detection, revealing superior toughness in laser-assisted laminates compared to autoclave counterparts. Altering laser power and compression force impacted polypropylene resin distribution, influencing hybrid interlayer peel strength. The inclusion of braided materials and elevated mold temperature proved effective in minimizing lamination warpage in GF/PP laminates.

Study on Multi-Span Tension Coupling Relationship of Gravure Printed Electronic Equipment

To improve the performance of the tension control system in gravure printed electronic equipment, it is necessary to study the tension system model of gravure-printing electronic equipment. This paper focuses on the coupling characteristics of multi-span tension systems. Firstly, based on the single-span tension model, the mathematical model of the printing tension subsystem is established and simplified into a general multi-span tension coupling model. Then, using the relationship between the inputs and outputs of the system, the coupling model is simulated using MATLAB/Simulink and verified through experiments on the gravure printed electronic platform. Finally, the coupling relationship and influence laws among multi-physical quantities of the system are analyzed. The research results show that changes in the input web tension of the multi-span system will affect the steady-state tension values of all subsequent spans. Moreover, the speed change in a roller in the multi-span system will not only affect the steady-state tension value of its own span, but also cause transient tension fluctuations in all subsequent spans. The findings of this paper provide an important theoretical basis for the research of the tension system in gravure printed electronic equipment, contributing to the enhancement of printed electronic product quality.

Fiber tension prediction and control methods in automated fiber placement

Fiber tension prediction and control methods in automated fiber placement

OCT Angiography of the Retina and the Choroid in the Macula in Patients with Normal Tension Glaucoma and Primary Open Angle Glaucoma.

The aim of this study was to compare vessel density (VD) in the retina and choroid in eyes with primary open angle glaucoma (POAG), normal tension glaucoma (NTG) and controls. Patients with POAG, NTG and controls underwent OCT scanning of the macula and the disc followed by 6 × 6 mm macula OCT angiography (OCTA) imaging. Global and hemifield VD were recorded for the superficial (SVP) and deep (DVP) vascular plexus and the choriocapillaris (CC). The OCT thickness of the nerve fiber layer (NFL) and ganglion cell layer (GCC) was also measured. Data from 65 POAG, 33 NTG and 40 control eyes matched for age were analyzed. Mean SVP VD was lower in NTG and POAG eyes compared to controls (38.8 ± 5.3, 40.7 ± 6.8 and 48.5 ± 4.0%, p < 0.001). Mean DVP VD was lower in NTG and POAG eyes compared to controls (43.1 ± 6.1, 44.5 ± 7.6 and 48.6 ± 5.8%, p = 0.002). There was no difference in SVP VD or DVP VD between the glaucoma groups (p > 0.050). No difference was noted in CC VD between the groups (68.3 ± 2.3, 67.6 ± 3.7 and 68.5 ± 2.6%, p = 0.287). Lower SVP and DVP VD was seen in eyes with glaucoma compared to normal eyes. NTG and POAG eyes had similar VD loss. Eyes with glaucoma manifested similar CC VD compared to controls.

Comparative assessment of load-bearing capacities in bolted laminated bamboo lumber connections: A study on diverse reinforcement techniques

Laminated bamboo lumber (LBL), a renowned engineered bamboo composite known for its outstanding performance and sustainability, is extensively used in modern bamboo structured buildings. This study focuses on examining the effects of diverse reinforcement techniques, particularly self-tapping screws and tension control bolts, on the load-bearing capacity of bolted LBL connections with steel plates. In total, 24 specimens were categorized into 8 groups and subjected to monotonic loading tests. The test results demonstrate that the non-reinforced group clearly shows longitudinal splitting failure at the bolt position, followed by a decrease in load-bearing capacity after failure. In contrast, the group with self-tapping screws (ST) and tension control bolts (BT) exhibited fiber tearing at the lower part of the midspan, accompanied by section bending and damage. The final load-bearing capacity of the groups reinforced with single-row three-bolt self-tapping screws and tension control bolts showed an increase of 67.30 % and 52.95 %, respectively. Likewise, the groups with single-row four-bolt configurations also demonstrated significant reinforcement effects, with increases of 40.52 % and 29.66 %, respectively. Furthermore, DIC-3D analysis was employed to examine the displacement of the connection bolts, and the van der Put model was utilized to estimate the load-bearing capacity of bolted LBL connections under splitting conditions. Subsequently, finite element models were established and calibrated based on the experimental data. The results confirm that self-tapping screws and tension control bolts can serve as structural enhancements in the design of bolted LBL connections, providing effective reinforcement for existing engineering structures.

Three-year analysis of results, safety and progression in patients with open-angle glaucoma or ocular hypertension, undertaking trabecular microsurgery

AimTo evaluate the efficacy, safety, structural and functional progression following the insertion of iStent inject ® implants in patients with open-angle glaucoma or ocular hypertension at a tertiary-level hospital. Materials and methodsA retrospective study included 98 eyes (57 males and 41 females) with open-angle glaucoma or ocular hypertension, which underwent iStent inject W® implantation (Glaukos, Corporation, CA) between December 2018 and December 2022. Differences in intraocular pressure (IOP), the number of hypotensive eye drops used, and structural and functional tests were assessed between preoperative values and subsequent reviews during a follow-up period of one (n = 98), two (n = 55), and three years (n = 15) after surgery. ResultsAmong the 98 eyes studied, 85% were diagnosed with open-angle glaucoma (50% mild, 32% moderate, and 18% severe) and 15% with ocular hypertension. There was a statistically significant reduction in IOP compared to preoperative values for all visits except the 1-month (p = 0.36) and 3-year (p = 0.39) visits. Visual acuity increased from 0.39 ± 0.25 to 0.72 ± 0.24 (p < 0.01), considering that a significant portion of the interventions included cataract surgery. Before surgery, 66% of the sample used 2 or more hypotensive medications. Post-surgery, the number of hypotensive medications decreased (from 1.88 ± 0.84 to 0.21 ± 0.59 at 3 years) (p < 0.01), with an 88.9% reduction in the number of medications over three years. After surgery, 75% of cases did not require any medication.Regarding structural and functional tests, thickness of retinal nerve fiber layers (RNFL (p = 0.35), excavation / papilla ratio E/P (p = 0.31), visual function index(VFI (p = 0.06), and deviation mean (MD (p = 0.06) showed no statistically significant differences post-intervention. However, standard deviation of the pattern (DSM) did exhibit differences, decreasing from 5.46 ± 4.03 dB to 5.34 ± 3.48 dB (p = 0.02). ConclusionThe results of this study suggest that the iStent inject W® technique constitutes an effective and safe option for tension control and glaucoma treatment.

Advanced taper tension profile for improved control performance in roll-to-roll winding processes

Products coated with flexible film can be stored in wound rolls after the winding process. However, if the roll product experiences excessive internal stress, it can lead to various defects in the coated layer. To alleviate the stress within the wound roll, a taper tension profile is utilized to progressively reduce tension as the winding length increases. As a substantial amount of web is wound onto the core, the moment of inertia of the wound roll increases. It has been observed that, as the winding length increases, the tension control performance of the taper tension tends to deteriorate. We propose an advanced taper tension profile to enhance tension control performance and validates the effectiveness of this profile through winding experiments. It was observed that, compared to the parabolic taper tension, maximum tension error could be reduced by approximately 16.1 % throughout the winding process. This reduction in tension error enables the preservation of the radial stress reduction effect of the taper tension, resulting in a 13.3 % decrease in the maximum radial stress compared to the parabolic taper tension. The proposed taper tension profile contributes to a more uniform quality of the coated layer, especially as the maximum winding length is extended.

Modelling and control of tension in a flexible pipe tensile armour manufacturing process

Modelling and control of tension in a flexible pipe tensile armour manufacturing process

Visual Communication In Tourism Development (Study on Curug Cay Waterfall Tourism, Bukit Village, Semidang Lagan District, Central Bengkulu Regency)

This research aims to determine visual communication in tourism development in Bukit Village, Semidang Lagan District, Central Bengkulu Regency. Data collection techniques were carried out using interviews with research informants. The informant in this research was 1 informant, namely the social account manager for the Curug Cay waterfall. The data analysis technique uses qualitative descriptive analysis which consists of data reduction, presentation and conclusions. The research results show that visual communication in tourism development in Bukit Village, Semidang Lagan District, Central Bengkulu Regency is seen based on the Aesthetic Theory according to Dake (2015:98) which consists of Disambiguity and Meaning, Control of Direction, Tension, Unity and Realism. It can be seen that the visual communication carried out by Bukit Village in promoting the Curug Cay waterfall tourist attraction is through social media such as Facebook, Instagram and TikTok. In creating content, there are many things that must be considered, such as strategies for taking interesting pictures and videos so that they attract people's attention to visit the Curug Cay waterfall tourist spot.

Análisis a tres años de resultados, seguridad y progresión en pacientes con glaucoma de ángulo abierto o hipertensión ocular, intervenidos de microcirugía trabecular

AimTo evaluate the efficacy, safety, structural and functional progression following the insertion of iStent inject ® implants in patients with open-angle glaucoma or ocular hypertension at a tertiary-level hospital. Materials and methodsA retrospective study included 98 eyes (57 males and 41 females) with open-angle glaucoma or ocular hypertension, which underwent iStent inject W® implantation (Glaukos, Corporation, CA) between December 2018 and December 2022. Differences in intraocular pressure (IOP), the number of hypotensive eye drops used, and structural and functional tests were assessed between preoperative values and subsequent reviews during a follow-up period of one (n=98), two (n=55), and three years (n=15) after surgery. ResultsAmong the 98 eyes studied, 85% were diagnosed with open-angle glaucoma (50% mild, 32% moderate, and 18% severe) and 15% with ocular hypertension. There was a statistically significant reduction in IOP compared to preoperative values for all visits except the 1-month (p=0.36) and 3-year (p=0.39) visits. Visual acuity increased from 0.39±0.25 to 0.72±0.24 (p<0.01), considering that a significant portion of the interventions included cataract surgery. Before surgery, 66% of the sample used 2 or more hypotensive medications. Post-surgery, the number of hypotensive medications decreased (from 1.88±0.84 to 0.21±0.59 at 3 years) (p<0.01), with an 88.9% reduction in the number of medications over three years. After surgery, 75% of cases did not require any medication.Regarding structural and functional tests, thickness of retinal nerve fiber layers (RNFL (p=0.35), excavation / papilla ratio E/P (p=0.31), visual function index(VFI (p=0.06), and deviation mean (MD (p=0.06) showed no statistically significant differences post-intervention. However, standard deviation of the pattern (DSM) did exhibit differences, decreasing from 5.46±4.03dB to 5.34±3.48dB (p=0.02). ConclusionThe results of this study suggest that the iStent inject W® technique constitutes an effective and safe option for tension control and glaucoma treatment.