Journal of Mechanical Engineering, Automation and Control Systems: Table of Contents

Numerical study of flow characteristics around rectangular cylinders in tandem

Hossain, Md Mosharrof — 2021-02-18T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 1, 2021, p. 36-43.
Md Mosharrof Hossain, Muhammed Hasnain Kabir Nayeem, Md Abu Taher Ali
The phenomena of mean pressure distribution around two square cylinders in tandem has been carried out. Also the mean velocity distribution in the wake of the two cylinder are studies. The Navier-Stokes equation for conservation of momentum and the continuity equation for conservation of mass are used to study the pressure and velocity distribution for various longitudinal spacing of the cylinder. The turbulent k-ω stationary flow at a high Reynolds number of Re= 6.5e4 is used to simulate single-phase flow. A critical longitudinal spacing equal to four times the side dimension of the square cylinder (L/D= 4) is investigated. Beyond that critical spacing both the cylinders are subjected to drag force. When L/D < 4 only the downstream cylinder is subjected to negative drag. Also, the form of the streamline profile behind upstream cylinder is different from that of single cylinder. However, beyond L/D= 4 the nature of the pressure behind both of the cylinder becomes kind of like that of the single cylinder.

Study of electromagnetic pulse (EMP) effect on surveillance unmanned aerial vehicles (UAVs)

Ibeobi, Samuel — 2021-05-03T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 1, 2021, p. 44-53.
Samuel Ibeobi, Xuchao Pan
The contemporary deployment of unmanned aerial vehicles (UAVs) for commercial purposes and electromagnetic pulse (EMP) threat to mechatronic devices necessitates the study of EMP on surveillance UAVs. This research paper describes the effect of EMP interference on the structure, communication and cabling circuit of the UAV. This was achieved using the CST microwave studio with an induced plane wave referring to MIL-STD464 and applying the transmission line matric solver method. The cable field coupling for bi-directional, uni-directional radiation and uni-directional irradiation were carried out with a constant resistive load of 50 Ω and the induced coupling currents and voltages, current in space domain, TLM mesh is obtained indicating the susceptibility of the UAV under different conditions of EMP interference and the electromagnetic distribution in the UAV circuit layout. Experimentally, the UAV is setup with an EMP generator and its response was observed at 12 m, 10 m and 8 m from the radiation source with the corresponding field strengths.

Design, analysis and fabrication of a fully articulated helicopter main rotor system

Ahmed Shamol, Arafat — 2021-06-11T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 1, 2021, p. 54-64.
Arafat Ahmed Shamol, Samin Yaser Ahmed, Md. Ariful Islam Shubho, Towsibur Rahman
This study describes an integrated framework in which the basic elements of Aerospace Engineering (performance, aerodynamics and structure) and functional elements (suspension, visibility and production) are integrated and considered. In this study, a fully functional rotor system has been fabricated that can be used as one of the training resources for Aeronautical students. For making the rotor system, various parts of the system have been designed on Solidworks and complete mechanism has been simulated with ANSYS. System analysis has been done at various RPM's and Angles of Attack (AOA). In terms of merit the right items have been selected and processed to provide them with the right shape. In terms of the design and implementation, various machines such as gas welding, arc welding, CNC milling and radial machinery have been used. Certain parts such as electric motors, linear actuators and loading cells have been used. All the fabricated components and electric motor, actuator, load cells are then assembled. This rotor system can produce less lift due to high dead weight and low power motor and having some safety issues.

Investigation of single valued motions in the vibro-impact system in case of harmonic force

Ragulskis, K. — 2021-06-30T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 1, 2021, p. 65-76.
K. Ragulskis, L. Ragulskis
It is determined that vibro-impact systems in practical applications generate a number of problems because of the fact that in the regimes in which steady state motions take place multivalued motions are observed. Here it is shown that in a definite investigated case multivalued stable regimes of motion do not exist in the system. Here the investigation of single valued solutions is performed. They are especially useful for practical applications according to the performance of impact processes. The presented graphical relationships enable to choose the regimes suitable for practical applications that are with decaying impacts as well as stationary stable regimes.

Four-dimensional trajectory optimization model with priority in continuous time period

Li, Meng — 2021-08-06T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 2, 2021, p. 77-86.
Meng Li, Jianyu Chu, Yinfeng Li, Xianjie Wu
This article aims to mitigate the imbalance of capacity and flow in airspace. Targeting to minimize the total delay time, taking the real-life sector operation and aircraft flight rules into consideration, with constraints of sector capacity limit and minimal time interval, the principle to prioritize aircraft when the delay occurred was raised. A trajectory planning model with the priority of aircraft was then established in the model of trajectory based on operation in a continuous period. The traditional genetic algorithm was also improved through the strategy of enhanced elitism preserving and double-stranded chromosome structure. Case studies indicated that the proposed trajectory planning model and solution algorithm have contributed to, over the two periods, an average reduction of 71.77 % in the delay time on optimization effect, and an increase of 19.48 % in the calculation speed. In this case, the model appears to, in a relatively short time, provide a trajectory allocation strategy with security and timeliness, for aircraft operated in consecutive periods. As a result, the sectors can operate without any conflicts while effectively reducing flight delays, minimizing the traffic congestion and potential accidents, so as to take the most advantages of sector resources allocation.

Vibration characteristics analysis and structural improvement of natural gas venting ignition pipeline

Chen, Yong — 2021-10-12T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 2, 2021, p. 125-134.
Yong Chen, Jinjin Tan, Shuxian Tian
In order to study the flow-induced vibration characteristics of the natural gas vent pipeline under the internal flow field, taking the gas transmission station pipeline as an example, the ANSYS Workbench software was used to establish models under two working conditions, uncoupling and fluid-solid coupling, for modal analysis, and analyze and compare the calculation results and propose a structural improvement plan. The results show that the maximum amplitude of the first three modes under the two working conditions is concentrated on the riser mouth, and the amplitude under the fluid-solid coupling condition is slightly larger than that of no coupling; the inner diameter of the pipe elbow is large and the pressure is small, and the outside diameter is small and the pressure is small. Large, this instability will increase the air pulsation of the flow field. In the improved scheme, adding a restriction on the top to increase the rigidity of the pipeline can significantly reduce the maximum amplitude of the gas pipeline; adding an orifice to eliminate air flow pulsation has a certain effect on reducing the maximum amplitude and natural frequency, and the combination of the two can make the pipeline more stable. The research results of this paper can provide improved ideas for vibration reduction at the natural gas venting operation site.

Parameter optimization of AISI 316 austenitic stainless steel for surface roughness by Grasshopper optimization algorithm

Jawade, Samidha — 2021-10-18T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 2, 2021, p. 87-97.
Samidha Jawade, Omkar K. Kulkarni, G. M. Kakandikar
This article describes the optimization of processing parameters for the surface roughness of AISI316 austenitic stainless steel. While experimenting, parameters in the process like feed rate (fd), speed (vc), and depth of cut (DoC) were used to study the outcome on the surface roughness (Ra) of the workpiece. The experiment was carried out using the design of experiments (DOE) on a computer numerical control (CNC) lathe. The surface roughness is tested for three conditions i.e. Dry, Wet, and cryogenic conditions after the turning process. Samples are step turned on CNC Lathe for all three conditions with a set of experiments designed. The response surface methodology is implemented, and mathematical models are built for all three conditions. The nature-inspired algorithm is the best way to get the optimal value. For the discussed problem in the paper, nature-inspired techniques are used for obtaining the optimum parameter values to get minimum surface roughness for all set conditions. The Grasshopper optimization algorithm (GOA) is the technique that is the most effective method for real-life applications. In this research, GOA is used to get optimum values for the surface roughness (Ra) at Dry, Wet and cryogenic conditions. Finally, results are compared, and it's observed that the values obtained from GOA are minimum in surface roughness value.

Dynamic performance of engine timing transmission system with RU type synchronous belt

Hu, Qingming — 2021-11-11T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 2, 2021, p. 109-124.
Qingming Hu, Junpeng Hou, Dandan Sun, Jianhua Guo
The dynamic characteristic of the timing system has a significant impact on the performance of the engine's NVH. With low contact stress and strong anti-interference ability, the arc tooth synchronous belt was adopted by engine timing transmission system. The multi-body dynamics model of the in-line four cylinder engine timing system was established. We explored the influence of crankshaft speed and initial tension on the dynamic performance of the engine timing system. The result shows when the crankshaft speed V= 2000 r/min and the initial tension of the synchronous belt F= 300 N, the load distribution of the RU type synchronous belt teeth root is more uniform. The stress is 0.2474 N/mm2 lower than the average value, and the transverse vibration amplitude decreases by 0.3067 mm. Under this circumstance, the fluctuation amplitude of camshaft angular velocity is 6.5312 rad/s lower than the maximum average amplitude, so the transmission error is reduced by 37.95 %. The fluctuation amplitude of interference value decreases by 0.3413 mm, and the fluctuation amplitude of interference velocity decreases by 263.8908 mm/s. The synchronous belt based engine timing transmission is more stable and the dynamic performance is better. It laid a solid foundation for the optimization of the tooth profile and load conditions of the engine timing system.

PSO optimum control strategy of 7 degrees of freedom semi-active suspensions

Qiao, Jubin — 2021-12-15T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 2, 2021, p. 98-108.
Jubin Qiao, Yeonsung Choi, Fuqiang Yang
The performance of vehicle body vibration and ride comfort of active or semi-active suspension with proper control is better than that with passive suspension. It is important to use simple, reliable, effective and low-cost optimal control methods to control the vehicle suspension. An important issue in the optimal control of vehicle semi-active suspension is to determine the weighting coefficient reasonably. This paper established a whole-car model of semi-active suspension systems with 7 degrees of freedom in Matlab, built optimum control system with system function, and then optimized the weight of control system by Particle Swarm Optimization (PSO) [1]. The results show that under different road input, the seven-degree-of-freedom control model for the whole vehicle controlled by particle swarm optimization algorithm can obtain better control effect, and effectively improve the comprehensive performance of the semi-active suspension system, both the vehicle's ride comfort and handling stability.

Identification of shallow cracks in rotating systems by utilizing convolutional neural networks and persistence spectrum under constant speed condition

Rezazadeh, Nima — 2021-12-15T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 2, Issue 2, 2021, p. 135-147.
Nima Rezazadeh, Mohammad-Reza Ashory, Shila Fallahy
The positive benefits of early faults detection in rotating systems have led scientists to develop automated methods. Although unbalancing is the most prevalent defect in rotor systems, this fault normally is accompanied by other defects such as crack. In this article, an effective self-acting procedure is addressed in identifying shallow cracks in rotor systems throughout the steady-state operation. To classify rotor systems suffering cracks with three various depths, firstly, healthy and cracked systems are modeled by employing the finite element method (FEM). In the following, systems' vibration signals are calculated in different situations numerically; for pre-processing stage, the persistence spectrum is implemented. Finally, by using a supervised convolutional neural network (CNN), rotor systems are classified by regarding the crack depths. The result of the testing step revealed that this hybrid method has rational capacity in distinguishing shallow cracks in steady-state operation where many other methods are somehow powerless.

Threshold analysis method for aircraft avoiding convective weather

Xiao, Shumin — 2022-06-30T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 3, Issue 1, 2022, p. 35-46.
Shumin Xiao, Yinfeng Li, Ranran Shang, Lu Yang, Xiujie Wei
Convective weather is an important weather phenomenon that affects aircraft operation, and the determination and analysis of convective weather characteristic thresholds is the basis and premise for airspace availability analysis and aircraft diversion. This paper innovatively proposes a threshold analysis method for aircraft to avoid convective weather. Firstly, the historical meteorological data and the track data are adopted in spatiotemporal and synchronous fusion. Secondly, the K-means clustering algorithm is used to determine the characteristic threshold range of the aircraft to avoid convective weather. Then, combined with the random forest classification algorithm, each threshold is again classified 0-1 through machine learning to determine the best avoidance threshold for weather features. Finally, the new construction index evaluation is used to evaluate the reliability of the algorithm. According to the threshold analysis method, the radar reflectivity factor is taken as the research object to carry out an example analysis. The example shows that when the radar reflectivity value is 34 dBZ, the accuracy rate is 96.58 %, the false alarm rate is 2.45 %, and the missing alarm rate is 0.97 %, all of which are better than the decision tree method, thus verifying the reliability and practicability of the algorithm.

Effect of the geometrical parameters on the vehicle's moving stability

Ye, Xiaobin — 2022-06-30T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 3, Issue 1, 2022, p. 1-8.
Xiaobin Ye, Vanliem Nguyen, Mingrui Ke
To enhance the moving stability and safety of vehicles, kinematics and dynamics model of the vehicle consisting of a guided front wheel and a free rear wheel is established based on the model of a four-wheeled vehicle when the vehicle moves on the curve-road. The effect of the geometrical parameters and dynamics parameters including the factor of the moving stability, vehicle moving speed, lateral stiffness parameters of the front and rear wheels, vehicle mass, vehicle length on the vehicle moving stability and safety is then simulated and analyzed, respectively. The research results indicate that the operating parameters of the vehicle greatly affect the vehicle moving stability. The lateral stiffness parameters of the front and rear wheels should be increased while the vehicle mass needs to be reduced in the operating condition of the vehicle to enhance the vehicle moving stability. Besides, the vehicle length L should be reduced and the longitudinal distance of a needs to be distributed by 0.95×a to further improve the vehicle moving stability.

Nonlinear dynamic analysis and defect detection of gears

Er-raoudi, M. — 2022-06-30T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 3, Issue 1, 2022, p. 9-22.
M. Er-raoudi, M. Diany, H. Aissaoui, M. Mabrouki
In the current work, the nonlinear dynamic behavior of an eight degrees of freedom gear system is investigated. Tooth crack is introduced into the model. The main sources of excitation are the time varying mesh stiffness (TVMS), time varying mesh damping, backlash and friction inter teeth. By using the potential energy method applied into the cantilevered beam, the TVMS is calculated. The backlash is considered as a dead zone. The effect of backlash, friction and tooth crack on the vibration frequencies is highlighted. The crack detection is based on the time-frequency analysis.

A comparative analysis of different approaches used for modelling and solving differential equations in Simulink/MATLAB

Mohindru, Pankaj — 2022-06-30T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 3, Issue 1, 2022, p. 23-34.
Pankaj Mohindru, Pooja Mohindru
In the paper, two new methods are developed and examined to implement a transfer function based approach in solving differential equations with Non-Zero initial conditions. A significant amount of time and effort is needed for solving differential equations theoretically or manually. Also, the obtained mathematical solutions to equations that represent various dynamic systems provide no graphical picture of the result. Using Simulink/MATLAB for modeling differential equations make the task of analyzing the behavior of systems easy and quick for the user. Beside, symbolic solutions and visual plots/graphs of the simulated results can be easily obtained and analyzed. Simulink uses different approaches to model a dynamic system such as differential equations in time domain (integrators based) or transfer function based and state space based. The paper addresses and compares different approaches used in Simulink for implementing block diagram based mathematical models of differential equations with non-zero initial conditions. Customarily, a transfer function based approach is used for analyzing systems with zero initial conditions. The paper demonstrated how to use a transfer function based approach for solving differential equations with non-zero initial conditions and two ways are devised to successfully implement the approach. To conclude, dynamic behavior of circuit and systems is analyzed and examined by obtaining graphical solutions with different approaches for chosen system parameters.

Analysis of forced oscillations of wheelset bouncing from multiplicative perturbation specified by harmonic function

Nikolaev, Viktor — 2022-12-28T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 3, Issue 2, 2022, p. 47-56.
Viktor Nikolaev, Janat Musayev, Algazy Zhauyt
The article analyzes the movement of a wheelset along a path that is unequal in length with wave wear of the rails. The authors studied the influence of a force external disturbance on the parametric system “wheel-rail”. The problem under consideration is solved on the basis of a mathematical model of the interaction of a wheel pair and an unequal track, taking into account the additive effect of unequal stiffness on a railway vehicle. It is shown that taking into account the longitudinal uneven elasticity of the railway track makes it possible to more accurately determine the resonant regions and evaluate the decrease or increase in the acceleration level and the amplitudes of bouncing of the unsprung mass of the rolling stock.

Design and analysis of experimental adaptive feedback system for active noise control (ANC) in a duct

Anachkova, Maja — 2023-05-05T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 4, Issue 1, 2023, p. 1-16.
Maja Anachkova, Damjan Pecioski, Simona Domazetovska, Dejan Shishkovski
The limitations of passive noise control methods impose a need for new technical solutions to solve the problem of reducing low-frequency noise, which is considered to be a dominant component of noise disturbance. In recent years, the subject of intensive research are the active noise control systems, which have aroused considerable interest and represent a promising solution to the problem of low-frequency noise control. This paper proposes a robust methodology for simplified design and analysis of an experimental active noise control system for real-time control of acoustic environment in a duct. The proposed feedback control model is based on using the LMS algorithm, combined with FxLMS algorithm for estimation and neutralization of the secondary path in the electro-acoustic system. The study shows the potential of the FPGA module and the Real-time module of cRIO from National Instruments, combined with the LabView software environment when applied in adaptive system for active noise control. The reliability and validity of the developed active noise control system is tested for a frequency range of 100 to 1000 [Hz], by measuring the amplitude-time domain in [V] and sound level in [dB]. The comparison of the experimental results shows great efficiency of the system at lower frequency range from 200 to 400 [Hz], where a maximum reduction in sound level achieved at a frequency of 200 [Hz] is 14 [dB] or 17 [%]. A significant sound level reduction is also achieved at both 300 [Hz] and 400 [Hz] which is 12 % or 10 [dB] in both cases. Given the analysis of the challenges and opportunities of the developed active noise control system, recommendations for advancements and future work are proposed.

Prospects of robotics in food processing: an overview

Wakchaure, Y. B. — 2023-06-21T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 4, Issue 1, 2023, p. 17-37.
Y. B. Wakchaure, B. K. Patle, Sachin Pawar
Mechanical progressions in different spaces have widened the application skyline of advanced mechanics to an unbelievable degree. Packaging and processing are some of the important aspects involved in the food industry. As the global population continues to rise with increasing consumer demand for a wider variety of food products, food manufacturing is exploring various strategies, techniques, and methods to meet the demand and adapt to the change. Industrial robots are being integrated into every part of the food manufacturing sector to increase production rates and improve food quality and hygiene. The introduction of more stringent legislation is forcing the food sector to update its production process. On the vigorous review of 50 papers, this paper provides a comprehensive review of robotics in food processing and investigates its analysis in terms of the level of automation applied in various food processing industries. The expectation of food-Robo in the food sectors and robotics with an optimized protocol to fetch various ingredients and shape them into a final product.

Rigid-flexible coupling modeling of the dual-rotor system for aero-engine

Ma, Pingping — 2023-10-31T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 4, Issue 2, 2023, p. 38-51.
Pingping Ma, Yuehui Dong, Hangqi Zhao, Yang Li, Muge Liu
The dual-rotor system is the core component of advanced aero-engine. Establishing a reasonable, accurate, and efficient dynamics model is the key to studying the dynamics and vibration of the rotor system for aero-engine. This manuscript takes a representative aircraft engine dual-rotor system as a prototype, considers the rig-id-flexible coupling characteristics of different stiffness elastic supports and rotor structures, and establishes an analytical dynamic model of the dual-rotor system. Based on the established dynamic model, the natural char-acteristics of the dual-rotor system are analyzed. The model was validated using two different research methods: the rigid-flexible coupling multi-body system dynamics simulation platform ADAMS, and finite element analy-sis. The dynamic model of the dual-rotor system established in this paper can meet the requirements of hierar-chical rigid-flexible coupling of system and structure, overall mass distribution, and stiffness distribution. In particular, it can also effectively realize the simulation of multi-facet and multi-phase unbalanced vibration of the rotor system. The research methods of this paper can further enrich the basic theory of dynamics and vibration of the aero-engine rotor system.

Galerkin-Kantorovich variational method for solving saint venant torsion problems of rectangular bars

Ike, Charles Chinwuba — 2024-02-22T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 5, Issue 1, 2024, p. 10-22.
Charles Chinwuba Ike
The unrestrained torsional analysis of bars is an important theme in elasticity theory, first solved by Saint-Venant using semi-inverse methods. It has been considered and solved by several others using analytical methods and numerical procedures due to the importance in the design of machine parts under torsional moments. In this paper, the Saint Venant torsion problem is solved for rectangular prismatic bars using Galerkin-Kantorovich variational method (GKVM). The work presents a detailed theoretical framework of the problem, deriving using first principles considerations the stress compatibility equation in terms of the Prandtl stress function ϕ(x,y). The derived domain equation which is required to be satisfied over the rectangular cross-sectional domain is a partial differential equation of the Poisson type. GKVM is adopted as the solution method for finding the solution to the domain equation. The unknown Prandtl stress function ϕ(x,y) is assumed, following Kantorovich method to be a product of an unknown function for fx sought to minimize the Galerkin-Kantorovich variational functional (integral) (GKVF) and a known function (y2-b2) which satisfies the boundary conditions at all boundary points in the y-direction, that is, at y=±b. The resulting GKVF is a simplified functional whose integral is a second order inhomogeneous ordinary differential equation (ODE) in fx. The integrand is solved to find fx leading in a full determination of the Prandtl stress function. The expression for stresses, torsional moments and torsional parameters are then found and they satisfy the boundary conditions and the domain equation. The results for the torsional moments and torsional parameters are identical to previous results obtained using double finite sine transform method (DFSTM), and analytical methods. The merit of GKVM is that it has led to the exact solution of the unrestrained torsion problems.

Influence of sliding wear on contact characteristics based on 3-D wheel/rail contact model

Han, Jihao — 2024-02-23T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 5, Issue 1, 2024, p. 1-9.
Jihao Han, Yunpeng Wei, Tao Yang
During the process of starting, braking and running of the train, sliding contact between wheel and rail occurs. The wear caused by sliding contact exerts a noteworthy influence on the contact characteristics of wheel/rail. To analyze these characteristics, a three-dimensional wheel/rail contact wear model is established, and the contact characteristics at different wear depths are studied. The results indicate that at initial contact, the wheel/rail contact patch is approximately elliptical in shape and its area is 122.5 mm2. The von Mises stress of the wheel and rail is maximum in the subsurface at a distance of 2 mm from the contact interface, with maximum values of 559 MPa and 628 MPa respectively. When the wear depth is less than 0.5 mm, the wear depth, contact area and size increase quickly. As the amount of wheel contact wear increases, the maximum contact stress gradually decreases and the contact stress becomes uniform. In addition, the calculation results indicate that the contact patch shape does not always remain elliptical, the shape can change from elliptical to rectangular as the wear depth increases. As the increasing of wear amount, the contact stress gradient on the inner side of wheel contact surface increases.

Exciters of vibrations with two pairs of impacting surfaces

Ragulskis, K. — 2024-06-18T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 5, Issue 1, 2024, p. 23-35.
K. Ragulskis, P. Paškevičius, L. Ragulskis
Exciters of vibrations of the type when one vibrating mass performs impacts into two immovable supports, which are located on the opposite sides with respect to the mass, are investigated. Here because of the connection of the vibrating mass with the supports the system may have the point of equilibrium located at equal or different distances from the impacting surfaces. Also, because of the difference of coefficients of restitution of impacts the system may have symmetric or non-symmetric laws of motions of the vibrating mass. Such systems are important in pipe robots and other engineering devices. Typical results of investigation of dynamics of such systems are obtained. The presented results can be used in the process of design of systems with vibrators having two impacting pairs. Investigations are performed by using analytical as well as numerical methods (calculations are performed by C++ Builder Community Edition, Newmark constant average acceleration method is used for numerical integration of equations of motion). The obtained typical graphical relationships show symmetric as well as unsymmetric regimes of motion and enable to perform their comparison. The basic novelty of this paper is the investigation of unsymmetric regimes of motion.

A rolling bearing fault diagnosis method based on Compressive sensing and Local characteristic-scale decomposition

Jo, Myong-Jin — 2024-08-09T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 5, Issue 2, 2024, p. 36-55.
Myong-Jin Jo, Su-Jong Kim, Tong-Chol Choe
Rolling bearings are an important part of the system with rotating parts. In the past, the rolling bearing fault diagnosis was based on the envelope of the bearing vibration waveform and FFT analysis to identify the fault and classify the fault type by the feature frequency. In addition, they proposed a method to perform signal processing by decomposing the envelope EMD to improve the diagnostic accuracy. However, this method is computationally intensive due to the iterative computation based on the reduced averaging method, and the convergence rate is different depending on the signal characteristics, which makes it difficult to perform real-time functions and consume a lot of memory space for data communication. In this paper, a method for diagnosing faults in rolling bearings based on compressive sensing (CS) and local characteristic-scale decomposition (LCD) is proposed and the effectiveness of bearing fault diagnosis method is verified by numerical experiments. In this paper, we propose a method to improve the diagnostic accuracy and shorten the computational time by identifying characteristic frequencies of the bearing fault from the Hilbert envelope spectrum of the components decomposed by the LCD after preprocessing and signal filtering of vibration signals based on CS.

Solving time-varying mesh stiffness of spur gears based on improved potential energy method

Zhang, Hao — 2024-09-10T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 5, Issue 2, 2024, p. 56-65.
Hao Zhang, Hongyuan Zhang
Meshing stiffness is an important factor in gear dynamics analysis. At present, there are many ways to calculate the meshing stiffness of gears, and we usually use the potential energy method to solve and calculate the meshing stiffness of healthy (faulty) gears. In this paper, the potential energy method, the improved potential energy method and the theoretical calculation method are used to solve the time-varying stiffness of the healthy spur gear pair, and the solution results are compared, which verifies the feasibility of the improved potential energy method to solve the gear meshing stiffness.

Research on active steering control strategy of line-controlled steering system based on MPC

Tong, Yuzhe — 2024-12-15T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 5, Issue 2, 2024, p. 66-78.
Yuzhe Tong, Xin Zhang, Xinxin Wang, Yuehong Bai, Jiao Yan
In order to improve the stability of the steer by wire (SBW) system during steering, this paper adopts a control strategy based on model predictive control (MPC) to achieve active steering control of the SBW system. Based on the fixed steering gain of the vehicle, design an ideal angular transmission ratio curve, and determine the stability of the vehicle's driving by controlling the yaw rate and center of mass lateral angle, achieving active steering function of the vehicle. Based on Simulink and Carsim platform, establish a vehicle model and analyze the frequency response characteristics of the steering actuator assembly to verify its working stability. The simulation results show that the designed control strategy can significantly improve vehicle handling stability.

Study the opportunity of using Arduino controller for practical stress measurement induced in mechanical loaded members

Hameed, Mohammed — 2025-01-17T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 6, Issue 1, 2025, p. 14-26.
Mohammed Hameed, Mohammed Saleh
The accurate assessment of stresses, strains and loads in components under working conditions is an essential requirement of successful engineering design. In particular, the location of peak stress values and stress concentrations, and subsequently their reduction or removal by suitable design, has applications in every field of engineering. The current work presents a technique for experimental strain measurement, where a data acquisition system have been composed of strain gauge sensors and an Arduino microcontroller. The measured signal conditioning is performed by means of strain bending sensor and then discretized by an analog-digital converter external to the Arduino. To realize the full-field measurement, the current measuring approach can be employed to determine the induced strain in multi points simultaneously. The significant features of the proposed measuring system are: sensitive, precise, economical, and compact size. For the purpose of results verification of the designed measuring device, experimental tests have performed on a cantilever beam and on a simply supported thin plate loaded at the center. An average percentage error was 5.7 % between analytical and experimental recorded strains in beam test. Also, in rectangular plate loading, an average percentage errors were 5.8 % and 4.1 % for the measured strains numerically and experimentally in X-direction and Y-direction respectively. The conducted results indicated a good agreement and demonstrate the accuracy of the proposed measuring system.

Nonlinear control of quadrotor trajectory with discrete H∞

Hasanlu, M. — 2025-01-19T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 6, Issue 1, 2025, p. 1-13.
M. Hasanlu, M. Siavashi
Fixed-wing drones generate lift using a wing similar to a conventional airplane, in contrast to rotary helicopters. As a result, these machines use energy solely for propulsion rather than to maintain altitude, making them significantly more efficient. These devices can traverse greater distances and cover larger areas, making them capable of mapping and monitoring specific points over extended periods. This article uses an analytical nonlinear approach to look at how discrete H∞ can be used as a robust controller to manage the path of a quadrotor. The main goal is to create a discrete H∞ nonlinear output feedback algorithm that can accurately track the position of the quadrotor while staying stable, even when there are unknowns, disturbances, or noise. The discrete formulation of this algorithm makes it especially suitable for multi-engine aircraft. By designing the controller in a discrete space first, transitioning to a continuous phase, and then reverting to discrete space for real-world application, more desirable and design-aligned results can be achieved. However, transitioning from continuous to discrete controllers may sometimes cause deviations from the design specifications. Designing the controller directly in the discrete space simplifies the overall process and enhances robustness.

Numerical simulation and optimization of sweep angle and depth variation studies for enhanced performance of savonius turbine

G, Madhan Kumar — 2025-01-22T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 6, Issue 1, 2025, p. 27-37.
Madhan Kumar G, Dhishan Merlin P M, Ranil R R, Venkatesh S
The straightforward and dependable Savonius turbine has a lot of promise for capturing wind energy in low-speed settings. However, poor aerodynamic performance frequently restricts its effectiveness. This study uses numerical modeling methods to examine how different sweep angles with constant depth affect Savonius turbine performance. The turbine's aerodynamic behaviour, torque production, and power coefficient were examined using parametric sweep optimization in various sweep angle with constant depth and fixed sweep angle with variable depth configurations. The results highlight the influence of sweep angle and depth on flow characteristics, lift to drag ratio, Torque and Power coefficient, leading to an optimized design with enhanced energy conversion efficiency. The findings provide valuable insights into improving the aerodynamic performance of Savonius turbines, contributing to their viability in sustainable energy applications.

A tunable stabilizing loop-based automatic voltage regulation system for overshoot reduction

Obari, Johnson A. — 2025-06-02T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 6, Issue 1, 2025, p. 38-57.
Johnson A. Obari, Abubakar Umar, Ramat U. Yusufu, Muyideen O. Momoh
The profundity of the extant technical exploits on the design of controllers for automatic voltage regulation (AVR) systems is enormous. Several approaches that involve the deployment of a proportional integral derivative (PID) controller and its variants have proven to offer great plausibility. Despite the performance and simplicity of the PID controller on the AVR system, the existence of overshoots is inherent in the design, which is detrimental to the safety of power equipment. This paved the way for the introduction of a stabilizing loop on the AVR system to strategically minimize the oscillations due to overshoots. In general, most stabilizing loops are characterized by filter with preselected gains which are often arbitrarily selected and not intelligently incorporated into the existing AVR architecture. This paper presents an AVR system with a tunable stabilizing loop. The essence of this is to intelligently enhance the performance of the PID controller in terms of overshoot reduction and reduce the sensitivity of the system to variation of parameters in an optimal fashion. The optimality of the design is realized by deploying some metaheuristic algorithms (Snake Optimizer (SO), Gazelle Optimization Algorithm (GOA), Smell Agent Optimization (SAO), Pelican Optimization Algorithm (POA), Dandelion Optimization Algorithm (DOA) and American Zebra Optimization (AZOA)), on a set of well-posed constraints to deduce the best combination of values of the parameters of the PID and the adjustable gain of the stabilizing loop, while the integral time absolute error (ITAE) is used as the cost function. Comparative analyses of the performance of this design topology with that of a PID-based design without a stabilizing loop reveal that the proposed design offers a significant reduction in percentage overshoot. More so, the credibility and suitability of the smell agent optimization algorithm (SAO) and the pelican optimization algorithm (POA), among the deployed algorithms, in ascertaining zero overshoot were justified. Furthermore, the robustness analysis was made on the developed design to reveal and ascertain its level of insensitivity to parameter variation.

Improved APF-based path planning for aircraft towbarless towing vehicle system

Ren, He — 2025-08-24T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 6, Issue 2, 2025, p. 58-74.
He Ren, Jiyan Qi, Xin Zhang
To enhance the maneuvering efficiency and safety of the aircraft towbarless towing vehicle (TTV) system, this study presents an optimized path planning method based on an improved artificial potential field (APF) algorithm. First, comprehensive kinematic and dynamic models are established, incorporating both lateral and yaw motions of the TTV system. Second, to mitigate obstacle interference challenges in complex airport environments, the proposed method introduces an innovative relative-distance safety factor and implements a dual-repulsive-force cooperative planning strategy, effectively overcoming the traditional APF algorithm’s limitations regarding goal unreachability and local minima. Furthermore, the integration of Bézier curves ensures curvature continuity in the planned path, thereby maintaining compliance with kinematic constraints. Finally, a constrained-motion TTV simulation model is developed to validate the algorithm’s performance. Simulation results demonstrate that, in static obstacle scenarios, the proposed method successfully enables autonomous path planning, generating smooth and collision-free trajectories. This approach offers a robust solution for ensuring stable and reliable operation of the TTV system in real-world airport environments.

Active fuzzy control of a suspension vehicle on wet and dry roads

Hasanlu, M. — 2025-12-31T00:00:00Z

Journal of Mechanical Engineering, Automation and Control Systems, Vol. 6, Issue 2, 2025, p. 75-90.
M. Hasanlu
This paper presents a co-simulation of MATLAB and CarSim to control and model a vehicle suspension system under different road surface conditions, either wet or dry, using an active fuzzy controller in MATLAB. CarSim is a professional vehicle simulation software capable of modeling nonlinear car dynamics with various uncertainties. These uncertainties are addressed by the fuzzy set approach due to its qualitative and robust control capabilities, effectively handling noise, disturbances (such as road conditions), and unknown parameters in CarSim’s vehicle model. The design of an active steering controller and rotational torque system using a fuzzy controller is crucial for enhancing road safety, especially given the increasing number of vehicle crashes. The research methodology varies based on the study's purpose, nature, and implementation capabilities. Accordingly, this research focuses on designing an integrated controller for an active four-wheel-drive system and direct rotary torque control using a fuzzy control method in the MATLAB Simulink environment. This study is analytical and functional, utilizing CarSim for simulation. A fuzzy logic-based integrated control system was designed for steady-state control to improve vehicle stability and steering. The controller adjusts the steering angle and torque to regulate the vehicle’s angular velocity and slip angle under various conditions. As tire performance changes during different maneuvers, the controller dynamically adapts its output to maintain optimal operation within the effective performance range. The significance of using fuzzy logic lies in its ability to handle non-linearity without requiring approximation, ensuring high accuracy. Additionally, it delivers excellent results in enhancing vehicle stability. The findings indicate that the controller significantly improves the vehicle’s dynamic behavior across different driving maneuvers compared to an uncontrolled vehicle.