Z. Li

• Opole University of Technology

Sealing technology is critical for the reliability and efficiency of mechanical systems, especially in rotating shaft applications. Traditional ferrofluid (FF) seals, while effective in narrow gaps (0.1–0.3 mm), face significant limitations in maintaining effective sealing under large gap conditions (more than 0.3 mm). To address this challenge, a...

This paper aims to implement the path planning problem for mobile robot in complex environments by golden jackal optimization algorithm (GJO). To address the shortcomings of original GJO algorithm, such as poor exploitation ability and ease of getting stuck in a local optimal region, a multi-strategy improved GJO algorithm (MSGJO) is proposed. Firs...

Inspired by the Kresling origami structure and its three stable state characteristics, a novel multimodal continuum robot (MCR) has been proposed in this paper, which achieve its own movement through gas-driven and actively elastic deformed Kresling origami. Airbags are utilized to auxiliary drive in this paper, which makes the specific plane of or...

An effective approach is proposed to evaluate the service life reliability of a multi-physics coupling structure of an insulated gate bipolar transistor (IGBT) module. The node-based smoothed finite element method with stabilization terms is firstly employed to construct an electrical-thermal-mechanical (ETM) coupling structure of the IGBT module,...

Space mining robots can develop and utilize abundant mineral resources in the outer space to solve the problem of the depletion of earth mineral resources. However, the motion errors of space mining robots in complex environments on the outer space surface of asteroids greatly hinder its applications. To bridge this research gap, a precise motion c...

Autonomous vehicles (AVs) are being enhanced by introducing wireless communication to improve their intelligence, reliability and efficiency. Despite all of these distinct advantages, the open wireless communication links and connectivity make the AVs’ vulnerability to cyber-attacks. This paper proposes an $L_{2}$ -gain-based resilient path follo...

To address the issue of high NOx emission from the combustion chamber, this work optimized the industrial machine structure to enhance the combustion performance. The analysis results indicated that the flue gas recirculation (FGR) could effectively reduce the combustion temperature and the distribution of high-temperature regions in the machine ch...

As an emerging research field, vehicle re-identification (Re-ID) can realize identity search between the vehicles, which plays an important role in the over-the-horizon perception of Vehicle-Infrastructure Cooperative Autonomous Driving (VICAD). At present, due to the lack of data sets, the relevant research on Vehicle-Infrastructure Cooperative (V...

For beam directors, tight optical path sealing and low rotational friction torque are critical aspects for the tracking and positioning performance. To maximize sealing pressure and minimize rotational friction torque, a magnetorheological fluid sealing (MRFS) structure design method based on multi-objective COOT (MOCOOT) algorithm optimizer was pr...

Capsule medical robots with unique application advantages have broad prospects for gastrointestinal detection, targeted drug delivery, medical assistance, and other fields. However, due to the complexity of the gastrointestinal environment and the limitations of the space magnetic field, robust motion control of capsule robots is still a challenge....

To address the problem of multi-source vibration in ultra-precision machine tools, a vibration reduction stand was designed by replacing passive damping components with magnetorheological dampers (MRDs). In this work, the structural parameters of MRDs were optimized using an improved pelican optimization algorithm (IPOA) to realize the maximum capa...

Fault diagnosis techniques of electrical motors can prevent unplanned downtime and loss of money, production, and health. Various parts of the induction motor can be diagnosed: Rotor, stator, rolling bearings, fan, insulation damage, and shaft. Acoustic analysis is non-invasive. Acoustic sensors are low-cost. Changes in the acoustic signal are ofte...

In order to address the problems of insufficient load capacity and rotor vibration, an active fluid-film bearing lubricated with magnetorheological fluid (MRF) is proposed. First, the geometry of the MRF fluid-film bearing is designed and its intelligent lubrication mechanism is analyzed to clarify its advantages. In addition, mathematical model of...

The machine vision-based non-contact vibration measurement is currently one of the hottest research topics in the instrumentation and measurement field. Single-frequency experiments are usually used to evaluate the non-contact measurement quality; however, in reality, it is difficult/impossible to quantify the non-contact vibration measurement usin...

Real-time and accurate 3-D object detection is one of the foundational technologies for environmental perception in autonomous vehicles. However, the existing second-stage anchor-based 3-D object detection algorithms have high accuracy, but they are challenging in terms of computation complexity and latency. Due to poor perception of spatial featur...

Nowadays, 3D printing has become a popular method among surgeons due to its merits in orthopedic treatments. In this method, polymeric biomaterials are deposited in a layer-by-layer manner to fabricate 3D objects that can be used as orthopedic implants and plates; however, 3D-printed implants or plates may lack properties required to bond with host...

Laser cladding technology has been widely used in the repair and surface strengthening of huge parts. In order to avoid interference between the laser head and the surface to be deposited, the laser cladding process needs to be completed in a tilted position in order to remanufacture some complex parts. The morphology of the cladding layer directly...

In this paper, considering the hydrogen production cycle coupled with the supercritical CO2 cycle, hydrogen is produced as a clean fuel along with power and heat production. Also, the world's need for clean energy doubles the solutions to achieve clean hydrogen energy. The investigated cycle has a supercritical CO2 cycle with a combustion chamber w...

The decision-making module that operates in real-time is extensively valued for promoting traffic flow stability and throughput during autonomous driving. However, it may become problematic for autonomous vehicles to conduct Lane-changing (LC) decisions for acceleration in challenging urban scenarios, which poses certain risks to driving safety. Th...

Surface defects of lithium batteries seriously affect the product quality and may lead to safety risks. In order to accurately identify the surface defects of lithium battery, a novel defect detection approach is proposed based on improved K-nearest neighbor (KNN) and Euclidean clustering segmentation. Firstly, an improved voxel density strategy fo...

A crucial method of maintenance in the metal removal manufacturing industry is machine vision-based fault diagnostics and condition monitoring of machine tools. The surface properties of the material are more affected by friction during tool-workpiece contact. Effective problem diagnosis is necessary for machine systems to continue operating safely...

Waste recycling is a critical issue for environment pollution management while garbage classification determines the recycling efficiency. In order to reduce labor costs and increase garbage classification capacity, a machine vision system is established based on the deep learning and transfer learning. In this new method, an improved MobileNetV2 d...

Large foreign object transporting by coal mine conveyor belt may lead to production safety hazards. To reduce safety accidents during coal mining, a large foreign object detection method based on machine vision is proposed in this paper. An adaptive weighted multi-scale Retinex (MSR) image enhancement algorithm is proposed to improve the captured i...

With the rapid development of artificial intelligence, various fault diagnosis methods based on the deep neural networks have made great advances in mechanical system safety monitoring. To get the high accuracy for the fault diagnosis, researchers tend to adopt the deep network layers and amount of neurons or kernels in each layer. This results in...

This paper aims to address the material and spatial uncertainties in the stochastic electric field problem by proposing two efficient algorithms based on the stable nodal integration method (SNIM). The random variables/fields are used to describe the material and spatial uncertainties and a generalized stochastic perturbation-SNIM (GS-SNIM) method...

Powerful belt conveyor is the crucial transportation equipment for coal mining. Keeping its stable operation is essential to ensure the coal mining efficiency. At present, damage detection systems based on machine vision are widely studied and deployed. Clear images are the foundation for successful damage detection. However, in the harsh environme...

Origami metamaterials have tremendous application potential in the fields of advanced deployable mechanisms, intelligent robots, and energy absorption devices. In this paper, we embed the flexible joints with metamaterial properties into the origami metamaterial structure, making the origami mechanism have simultaneous geometric nonlinearity and jo...

Structural health monitoring (SHM) has been recognized as a useful tool for safety management and risk reduction of offshore wind farms. In complex offshore environment, jacket structures of offshore wind turbines are prone to damages due to corrosion and fatigue. Effective SHM on jacket structures can substantially reduce their operation risk and...

In this study, three fins with rectangular shapes have been mounted within an elliptic enclosure to create a new thermal system. Numerical method for analyzing discharging of PCM inside the mentioned geometry has been scrutinized. With neglecting the low amount of velocity for liquid phase, the mathematical model has been derived for this problem....

Surface defects of lithium batteries seriously affect the product quality and may lead to safety risks. In order to accurately identify the surface defects of lithium battery, a novel defect detection approach is proposed based on improved K-Nearest Neighbor (KNN) and Euclidean clustering segmentation. Firstly, an improved Voxel density strategy fo...

Inspired by the strong nonlinearity of origami cartons, a novel origami-inspired constant-force mechanism (OriCFM) is systematically studied for obtaining a stable quasi-static constant force output. The proposed OriCFM is evolved by adding equivalent springs at horizontal and oblique creases of the rigid origami mechanism. Based on the geometry re...

The tobacco flavoring process is an important procedure in production stage. During the flavoring process, the cut tobacco is endowed with a unique flavor to stabilize the production quality. Most of the flavoring process in tobacco enterprises is finished in the drum, and the internal structure of the drum (including the number, angle and installa...

A computational approach is developed for multi-physics modelling of Insulated Gate Bipolar Transistor (IGBT) module considering the electrical-thermal-mechanical coupling effect. In this approach, the tetrahedral elements are used to build the finite element domains of an efficient IGBT model. Then, the discretized system equations of the IGBT mod...

Injection and mass diffusion of fuel jet released in the combustor of scramjet are the primary processes that improve scramjet engine performance. In this work, the presence of the strut fin inner the nozzle injector on the distribution and penetration mechanism of fuel jet at supersonic cross air stream is broadly investigated. The main novelty of...

In this essay, to satisfy the need for highest rate of heat release, the triplex pipe was equipped with fins on both pipes. Nanomaterial has been utilized to expedite the process involving single phase approximation for modeling purpose. The equations have been simplified with involving the approximation of no sensible impact of convection and solu...

An efficient injection system is essential for the advance of the scramjet engine for high-speed flight. In present study, the effects of lateral injection from the circular strut on the fuel mixing and distributions are comprehensively investigated. In this study, computational technique of CFD is used for the visualization of fuel mixing mechanis...

Trajectory planning is a crucial aspect of autonomous driving for energy conservation ans savings, especially in electric vehicles (EVs). A particular vehicle inverse dynamics model is nec- essary to calculate the required torque and steering control for following the target trajectory. Consequently, the energy consumption of an EV can be minimized...

With the miniaturization of medical equipment and the comfort of diagnosis mode, positioning has become a major challenge in the research of capsule robots. In order to realize the effective positioning of magnetically controlled capsule robots, a positioning method based on double-layer symmetric sensor array is proposed in this work. Firstly, a n...

When fusing the measurement data with different sampling frequencies from the light detection and ranging (LiDAR) and inertial measurement unit (IMU), their timestamps should be exactly aligned. However, in reality the timestamps of LiDAR and IMU are typically subject to different influences, which will inevitably generate the time delay error to r...

Global navigation satellite system (GNSS) signals cannot be received indoors, thus to deploy intelligent vehicles in underground car parks other localization methods are needed. In this paper, we use various carpark signs that are widely and uniformly distributed in underground parking lots as localization references. We propose a coarse-to-fine mu...

This paper investigates the problem of resilient dynamic event-triggered control for networked unmanned surface vehicles (USVs) with external disturbance in the presence of transmission delay and aperiodic DoS attacks. First, a networkbased USV control system model is constructed and converted into a state space. Second, a resilient dynamic event-t...

Due to the relatively cheap price of diesel, most Marine engines use diesel as Marine fuel, but its emissions contain a lot of carbon. To reduce carbon emissions, International Maritime Organization (IMO) has established an Energy Efficiency Design Index (EEDI) and Energy Efficiency Existing-Ship Index (EEXI). Currently, a popular way is to reduce...

The injection is one of the main factors to improve the heat transfer in the macro and microscale devices, especially in microchannels. The present research focuses on the impacts of injection velocity on heat transfer and fluid flow by utilizing computational fluid dynamics. The results claimed that the injections intensified both thermal and hydr...

Shape memory alloy (SMA) wires are one of the widely used materials for soft artificial muscles. However, SMA artificial muscles have two problems, including limited load holding ability due to their soft nature and slow response due to their long cooling time. The main contributions of this article are the developments of a controllable magnetorhe...

There are three motion stages for an industrial robot manipulator, including the acceleration stage, the constant velocity stage, and the deceleration stage. Aiming at reducing the residual vibration of the manipulator after the movement of the deceleration, a new method is proposed by configuring the movement parameters of the flexible manipulator...

The mixing efficiency of injection system inside combustion chamber of the scramjet significantly influence on the total performance of the hypersonic vehicles. In this study, the existence of the downstream ramp on the flow structure of hydrogen cross jet at supersonic air stream is comprehensively investigated. Computational fluid dynamic method...

The fuel injection technique is the most effective procedure in the combustion chamber of supersonic/hypersonic vehicles. This work tries to explore the impact of the nozzle type on the fuel mixing of four multi-jet at a supersonic air stream of Mach = 4. Three different nozzles of rectangular (1:4), (1:16), and arc injector (1:16) are examined to...

In recent years, considerable progress has been made in semantic segmentation of images with favorable environments. However, the environmental perception of autonomous driving under adverse weather conditions is still very challenging. In particular, the low visibility at nighttime greatly affects driving safety. In this paper, we aim to explore i...

Mixture of MWCNT nanoparticles and paraffin with melting point of 24.5 °C has been utilized for saving the energy inside the ventilating system. The utilized duct for transportation of air has various tubes containing the paraffin and four styles for such obstacles have been presented. Finite volume method for modeling the melting procedure was uti...

The suspension is one of the most vital systems in a vehicle. Its performance degrades over time due to road conditions. The suspension parameters of a moving vehicle are difficult or sometimes impossible to measure within the desired level of accuracy due to high costs and other associated impracticalities. In this work, we comprehensively investi...

The main emphasis of this work is placed on the problem of collaborative coverage path planning for unmanned surface mapping vehicles (USMVs). As a result, the collaborative coverage improved $BA^{*}$ algorithm ( $CCIBA^{*}$ ) is proposed. In the algorithm, coverage path planning for a single vehicle is achieved by task decomposition and level m...

In this research, all-inclusive efforts are performed to understand the impact of downstream ramp on fuel distribution of cross jet at high-speed flow inside the combustion chamber. Three different jet injectors have been examined to find the efficient injector (3-lobe, rectangular and circular nozzle) for this configuration. The simulation of the...

Aiming at the distributed flexible job shop scheduling problem under dual resource constraints considering the influence of workpiece transportation time between factories and machines, a distributed flexible job shop scheduling problem (DFJSP) model with the optimization goal of minimizing completion time is established, and an improved mayfly alg...

Due to the complexity of the production shop in discrete manufacturing industry, the traditional genetic algorithm (GA) cannot solve the production scheduling problem well. In order to enhance the GA-based method to solve the production scheduling problem effectively, the simulated annealing algorithm (SAA) is used to develop an improved hybrid gen...

The bottom pivot is a vital support device in the miter gate but often subject to poor lubrication and wear failures. Calculating the hydrodynamic lubrication characteristics of the bottom pivot is a complex three-dimensional (3D) problem, and most of existing models adopt simplified assumptions to reduce the calculation difficulty. To solve this i...

This paper numerically investigates cooling of a cubic pack of nine cylindrical type lithium-ion batteries. The pack is first equipped with three separate ducts to convey alumina (Al2O3)/water nanofluids (NFs), and all the assembly of battery cells and ducts are then dipped in a phase-change material (PCM). Simulations are carried out to investigat...

In this paper, the battery cooling is examined by placing a battery cooling system in the airflow path. The cooling system consists of 9 cylindrical battery cells so that a phase change material (PCM) surrounds them. PCM is housed in horizontal and vertical elliptical (ELL) and circular enclosures. The amount of PCM used in enclosures is equal and...

In this study, the phase transition process of porous carbon matrix (PCM) containing paraffin as phase change materials (PCM) in copper oxide nanoparticles (NPs) is explored utilizing the molecular dynamics (MD) simulation procedure. PCMs can cumulate and disseminate huge energy due to their high melting heat. In this way, the changes in the charge...

Due to the importance of examining the temperature of battery packs (BYP), a study on the temperature of a lithium-ion BYP with 9 cylindrical cells is performed in this article. The BYP is filled with phase change material (PCM) to better temperature uniformity on the battery cells. The batteries and the PCM pack are placed in an air channel with t...

A multi-case load spectrum compiling method is proposed in this study for dynamic modeling of a hydraulic excavator stick to simplify and accelerate the fatigue bench test. This new method includes a simplified criterion of small-load-omitting threshold based on the principle of invariable fatigue damage, an extreme value inference criterion based...

Hybrid bearing is a kind of bearing that uses ceramic materials instead of steel and other metal materials as rolling elements. It is often used to reduce (i.e., rolling or sliding) friction resistance. Although many published works have shown that hybrid bearings are more effective than ordinary bearings in reducing friction resistance, improving...

The velocity sensitive characteristic of the conventional linear magnetorheological (MR) damper is undesirable in the application of impact protection. It will induce large damping forces when the damper suffers high velocity impacts, whilst comprising the energy dissipation efficiency of the damper and posing a serious threat to occupants and mech...

The demand of accurate and real-time dynamics model has recently become critical for implementing effective vibration control in vehicles. The multibody dynamics method provides an appealing alternative for accurate modelling of closed-loop vehicles. In this work, vibration-suppression strategies for a vehicle traversing a bumpy road are proposed,...

A Cross-linked microencapsulated phase change material (MEPCM) was prepared using butyl stearate as the core material and isophorone diisocyanate (IPDI) and triethanolamine (TEA) as the reaction monomers, while a Linear MEPCM was prepared using 2,4-toluene diisocyanate (TDI) and diethylenetriamine (DETA) as the reaction monomers. The thermal stabil...