International Journal of Mechanical Engineering and Robotics Research

Novel Fuzzy Reinforcement Algorithm for Mobile Robot Navigation in Automated Storage

2024-02-20T13:53:30+08:00

Robots are used to move stored items in Automated storage (AS) to shelve and pickup items in warehouse depicted shelves. In this situation and many others, it is important to follow the shortest way so that the smallest time possible is taken to achieve the task. In this research, a Fuzzy Logic system with Q-Learning Reinforcement in order to achieve a better overall system. Reinforcement learning helps to adjust the rules and refine them towards the final goal, while avoiding difficult obstacles such as traps. This is done as an enhancement on a our previous work where Fuzzy Logic system was used alone. Simulation results are added to support the work done. It proved that this new system is much better than the previous one.

Vibration Analysis of Suspension System for 3DOF Quarter Car Model with Tire Damping

2024-01-15T10:47:42+08:00

This research focuses on vibration analysis of suspension system for quarter car model by theoretical and experimental apporach. The information obtained from the mathematical model can be used for analysis of the system. Three degree of freedom suspension system with tire damping is analyzed by using Matlab software. State space modelling is one of the best way of presenting differential equation. From the state space modelling, seat mass and sprung mass and unsprung mass displacement have been calculated. Accelerometer and data acquisition system are setup for experimental test of vibration system. Natural frequency and acceleration results is obtained with time domain response from experimental data. Sprung mass natural frequency for theoretical (1.23Hz) and experimental (1.134Hz) result are within the resonance condition (1Hz to 2Hz). Damping ratio of the experimental test is 0.22 and is getting by using the logarithmic decrement method. Comparison of theoretical and experimental results are found that the minimum percent deviation and less than the acceptable limit of under damped case.

Design and Position Control of a Robot with 5 Degrees of Freedom

2024-02-04T20:04:31+08:00

In the last decades, robotics and artificial intelligence have gained great importance due to their intervention in different industrial processes of which today humanity takes advantage of its maximum splendor. However, today there are many advanced robots with sophisticated controls, but none is focused on the supply of lemons. This research proposes the design of a manipulator robot with 5 degrees of freedom, as well as the control of its trajectories to perform the lemon supply function. To achieve this, kinematic and dynamic calculations of a manipulator robot were used, as well as programming codes in Matlab to obtain its trajectories, positions, speeds and accelerations. In addition, the proportional integral derivative (PID) tuner was used to obtain the appropriate values of the controller and to be able to generate the trajectories of the joints accurately.

Improving the Accuracy of the Surface Roughness Model in Grinding Through Square Root Transformation

2024-02-13T22:29:30+08:00

Surface roughness is a crucial parameter for mechanical products. To achieve small surface roughness, the grinding method is often chosen as the final machining process. The regression model of surface roughness forms the basis for controlling the grinding process and predicting surface roughness under specific conditions. The effectiveness of process control and the accuracy of predicted surface roughness depend on the precision of the surface roughness regression model. This study aims to enhance the accuracy of the surface roughness regression model by employing square root transformation. An experimental process was conducted with a total of eighteen experiments. In each experiment, three cutting parameters, including workpiece speed, tool feed rate, and cutting depth, were varied. Surface roughness was measured in each experiment. After conducting experiments, a surface roughness regression model was established, denoted as Model (1), without using any data transformation. The square root transformation was applied to convert the surface roughness dataset into another set of data. From this dataset, another surface roughness model, referred to as Model (2), was developed. Both models were used to predict surface roughness, and the predicted results were compared with the actual surface roughness in the experiments. Four parameters were used to compare Models (1) and (2), including the coefficient of determination (R-Sq), adjusted coefficient of determination (R-Sq(adj)), mean absolute error percentage (%MAE), and mean squared error (%MSE). All four parameters for Model (2) were superior to those for Model (1). The results confirmed that the square root transformation successfully improved the accuracy of the surface roughness regression model in grinding applications.

Dynamic Interaction of the TE-33A Diesel Locomotive and the Track in a Curve with a Radius of 600 Meters

2023-12-20T09:32:32+08:00

This article is about the indicators of dynamic qualities that ensure traffic safety, compliance with the rules of maintenance and maintenance were determined, with geometric inscribing, the forces acting on the crew were not determined, but it was assumed that they affect the location of the crew in the curve. To determine the forces acting on the crew and the path, depending on the steady-state speeds of movement along the curve, the so-called dynamic insertion of the crew into the curve is performed. At the same time, the greatest forces arising during the movement of this TE-33A locomotive along the curve are determined, when moving in the transition curve, individual elements of the locomotive (wheel pairs, wagon, bodywork) make complex movements.

Optimizing Mechanical Properties in Biodegradable Composites: Polypropylene and Corn Stalk Powder Fibers

2024-01-07T21:53:39+08:00

The purpose of this study was to investigate the microstructure and characteristics of biodegradable composites made from corn stalk powder fiber material and a polypropylene plastic matrix, using Scanning Electron Microscope (SEM) analysis. The issue of environmental pollution caused by plastic waste is a growing concern, with plastic waste accounting for an average of 10% of total waste production, and less than 1% of plastic waste being effectively decomposed due to the synthetic polymers used in their production. Developing biodegradable plastic materials, such as bioplastics, is one way to address this problem. In this study, different compositions of the composite materials were tested using SEM and microphotography. The composite materials consisted of a polypropylene plastic matrix with varying amounts of corn stalk powder fibers (5%, 10%, and 15%). The SEM results showed that the composition of 85% polypropylene plastic and 15% corn stalk powder had a more significant impact on the mechanical properties of the composites, due to a stronger bond between the plastic and polypropylene. Overall, this study provides important insights into the development of biodegradable plastic materials that can help mitigate the environmental impact of plastic waste.

Manuscript received February 8, 2023; revised March 22, 2023; accepted May 25, 2023.

Non-linear AUV Controller Design Using Logic-Based Switching PID Control

2023-12-28T10:10:11+08:00

The inspection of pipes without stopping pipeline operations is of industrial interest due to the inherent economic benefits. A pipe inspection robot design is proposed together with a suitable motion controller. The proposed robot is an Autonomous Underwater Vehicle (AUV) architecture that does not require shunting, draining or unearthing pipework for inspection purposes. This posed the challenge of controlling the AUV through a narrow pipe where manouvers are restricted. A set of general non-linear equations of motion were identified and refined using existing research and strip theory. The non-linear analytical model was implemented in Simulink to enable real-time monitoring and controller tuning. A non-linear controller based on a combination of classical PID theory and switching logic was developed to control the platform. The controller was transplanted into a Hardware-in-Loop (HIL) testing model developed with the Arduino and Simulink software suites. Pool tests measuring the parameters pitch and yaw angles showed that when operated independently with a 5° input, the maximum overshoot was 0.5° or 10% of the command value with a maximum angular velocity of 1.25°/s. When operated simultaneously, the overshoot rose to 30% with a constant error in the region of 1° over the target. Distance readings conducted with ultrasonic sensors to the pipe wall showed constant Sway-Heave bias errors from the centerline as −5 mm, and 4 mm, respectively, with an error range of 4 mm / −7 mm for Sway and 6 mm/ −4 mm for Heave. Pitch and heave motions were up to 18% faster than yaw and sway motions due to actuator orientation, with speeds of 6.25°/s and 40.57 mm/s, respectively. Despite the turbulence present during tests, the controller successfully drove the AUV to target positions through active flow and presented a reasonable basis for further refinement.

Manuscript received August 25, 2023; revised October 13, 2023; accepted November 29, 2023.

Load Pushing Capacity Analysis of Individual and Multi-Cooperative Mobile Robot through Symbiotic Application

2024-01-24T13:55:20+08:00

Certain missions require multiple mobile robots working together to accomplish it. There is a need, however, to determine the optimal configuration of modular mobile robots doing cooperative tasks to ensure high utilization and efficiency rate of the individual robot. This study proposed the use of a biosystem-inspired approach in assessing the influence of multiple robots to each other in performing a cooperative pushing task. The kinematics of pushing interaction at a single contact point was first discussed in the study to provide a solid foundation of the mission to be analyzed. Various dimensions in an experimental setup were also covered to better understand how these contribute to planar pushing. Through the resulting symbiotic coefficient, the study was able to determine the optimal configuration among the two, four, and six wheeled mobile robots pushing an object with various loads. The dominant coefficient for symbiotic relationship was classified as beneficial and only one was neutral. Although, the decreased values in the 3rd configuration with respect to the 2nd configuration gave the hint to a possible negative coefficient in the next configuration. The maximum level of distance at which an object can be pushed was also obtained. This was called the state of plateau wherein adding another module is no longer suggested as it will not improve the pushing capacity any further. Knowing these key points significantly helps in ensuring cost and work efficiency of a given configuration in performing different missions.

UIQuad I: A Low-cost and Modular Surveillance Quadcopter

2024-01-11T12:01:46+08:00

The paper presents the development of an Unmanned Aerial Vehicle (UAV) quadcopter, capable of both manual and autonomous flight modes, fitted with a camera to provide pictorial and video footage of any selected environment. The prototype of the quadcopter was built with an Ardupilot (APM) 2.8 flight controller which in-corporates a microcontroller in addition to an inertial measurement unit (IMU). All other components for the quadcopter including the frame, landing gear, Lithium Polymer (LiPo) battery, brushless motors, electric speed controllers, power module, telemetry module, propellers, and a GPS module were all carefully selected such that the final thrust to weight ratio of the drone will be in the range of 2.4:1 at full throttle. The mechanical, electrical and electronics components were coupled successfully. The prototype was tested in the manual mode of operation via a 6-channel radio transmitter with successful takeoff and landing operations. In its autonomous mode, an open source Ardupilot Mission Planner software was used for the control of the quadcopter. Flight missions with a specified paths, altitudes and speeds were tested and stable flight operations with no human input were achieved. Live communication was successfully established with the camera on board the quadcopter during flight operations via an open source, Sports XDV mobile application. The estimated cost for the construction of the prototype is ₦366,000. The proposed UIQuad I is a pioneering effort by the University of Ibadan’s Automation and Robotics laboratory in the development of quadcopter for surveillance of the university campus. This surveillance quadcopter can be used as it is or scaled up or down to suit agricultural, humanitarian, government, and industrial applications

Enhancing Hard Milling of SKD11 Steel: The Advantages of Al2O3 Nanofluid

2024-01-11T12:02:39+08:00

Recent machining processes have increasingly focused on the application of nanofluid. This research specifically explores the remarkable performance of nanofluid in the hard milling of SKD11 steel. A meticulous series of experiments was conducted to evaluate the impact of cutting fluids (dry, MQL, and nanofluid-based MQL) and cutting parameters (cutting speed, depth of cut, and feed rate) on surface roughness, cutting force, and cutting temperature. The Taguchi method was employed to determine the optimal values for cutting fluids and cutting parameters. Utilizing the L27 orthogonal array of Taguchi's experimental design technique, surface roughness, cutting force, and cutting temperature were thoroughly examined. The analysis of signal-to-noise response and ANOVA revealed that nanofluid demonstrated promising performance by enhancing surface roughness, reducing cutting force, and lowering cutting temperature during the hard milling of SKD11 steel

Drilling Performance of Aluminum Plates Under Manual Drilling Conditions

2024-01-25T10:51:08+08:00

Aluminum alloy is widely used in aircraft structural components. However, the high cutting force in the conventional machining often causes the burr formation and surface damage in the machined parts. To overcome the problems, a drilling unit, Soft-machining, was designed that can reproduce the manual drilling without human assistance where the force required to feed the tool is provided by a weight of mass W[g]. Thrust force in the soft machining was set at 40 to 110 N, the same level as in manual drilling and less than one-tenth of thrust force in general CNC machining. A total of more than 200 holes were drilled with the same drill. Amazingly, the soft-machining did not form visible burrs under almost all cutting conditions. Even in the drilling of stacked plates, the soft-machining can drill the through holes at the specified points and no noticeable defects were observed. This is considered to be related to the fact that the soft-machining shows different tool feed rate depending on the material even if the same load P is applied and the formations of burrs and other defects can be suppressed by optimizing the applied load P. From the results of this study, it is considered that the minimum load that can make cutting and tool feeding is optimize.

Increasing the Sigma Level and customer value in the Manufacturing Industry Motorcycle: a case study of Cover Components

2024-01-25T10:52:55+08:00

Motorcycles have several cover parts, and the Step Floor Cover is the most defective cover part with a defect rate of more than 3%. The Cover Step Floor has 3 types of defects which are broken, the classification bolt is not neat, and Black Dot. Based on the Pareto Chart, the most defective type of defect is the classification bolt is not neat and breaks. Those defects can lead to a gap between Cover Step Floor and Cover Floor Side. To overcome this problem, the Six Sigma DMAIC methodology can provide alternative solutions for improvement. In the Define phase, the steps consist of identifying the defect on cover parts, the production process, and making the OPC production of the cover step floor. The measurement phase can be conducted using Pareto Chart to measure the most prevalent defects, identify the CTQ in the production of cover parts, Control Chart to measure the UCL, CL, and LCL, and calculate the Sigma Level using DPMO. Support from Finite Element Analysis (FEA) is required to identify the pressure for the Cover Step Floor to make the alternative solution. Analyze phase, by using the Fishbone Diagram to know the root cause of the defect. In the improvement phase use the Failure and Effect Analysis (FMEA) to determine the most appropriate alternative solution. An alternative solution based on the highest RPN is used to design a tool called a Jig and Fixture which is used to hold and position the Cover Step Floor during the drilling process. The use of Jigs and Fixtures can increase process efficiency by increasing the Sigma value and decreasing the DPMO value; this proves that the use of Jigs and Fixtures is effective for reducing step floor cover defects and increasing customer value.

Numerical Test to Determine the Influence of Factors on the Weight of the Multi-layer Rope Reel of the Winch

2024-01-26T17:31:32+08:00

The winch are equipment used in many different fields of industrial. The drum is an important part of the winch. In the previous study, we designed one personal rescue winch for high-rise building rescue. Its key requirement is to be small and light enough to suit users. Many design factors of drums have not been fully investigated. In particular, the influence and importance of each factor on the drum weight need to be fully evaluated. The article establishes the process and studies the main factors affecting the drum weight of the rescue winch. The main influencing factors are materials and structural parts. This study uses numerical method with the support of INVEVTER software.The correctness of the model is verified through the analytical formula.The research results show that the material is the decisive factor to the drum weight of the winch. For the structure, the drum thickness is the decisive factor. When local stress effects are taken into account, the drum mass can be increased. The research results help us to choose the appropriate method to optimize the drum of the rescue winch in specific conditions.

Assessment of steel pipe-shaped structure under blast loading: A benchmark and parametric study using finite element approach

2024-01-26T17:36:54+08:00

The steel industry can be said to be the mother of all industries, which means that the steel industry has an important role in the development of the manufacturing and construction industries in the context of national economic development. Since steel is a key material in the industrial sector, the material must have high strength to withstand explosive forces or loads that may occur at any time. Accidental event is unavoidably dangerous if no countermeasure or forecast is provided as a reliable reference to design a mitigation or evacuation plan. Besides external loading, accidental loading, e.g., blast loading may occur inside an engineering object. Recently, many studies have been conducted on the response of geometric structures to accidental collisions and loads, including air blast loading. This research aims to analyse the structural response of steel pipe-shaped structure due to blast loading using the finite element method. The research method used is a simulation method to find out how the structure responds to blast loads and how much deflection occurs in the structure at each load variation. This study was designed and tested using finite element analysis on ABAQUS/Explicit. ABAQUS software is more focused on running simulations and retrieving the necessary data. Simulation validation was carried out with a comparative study of the experimental results in the research of Rushton et al. Analyses were conducted with numerical parameters (TNT loading and mesh size variation) and physical parameters (material variation). The analysis results show that numerical parameters (mesh variation) affect the accuracy of simulation data while physical parameters affect the performance of steel pipe-shaped structure.

Design of a Sliding Mode Controller for a Macpherson Suspension System to Simulate an LQR-Optimized Skyhook Model

2024-01-26T17:39:12+08:00

Abstract—The purpose of this project is to design and implement a controller to achieve a desired displacement and velocity of a sprung mass in a suspension system dynamic model of a vehicle at certain times. In numerous applications, the dynamic response of the Skyhook model is considered the optimal response of a suspension system. As a result, in this project, the response of the Skyhook model is first improved by use of an LQR controller, and then using the sliding mode controller, the response of the realistic car model, represented by a Macpherson suspension system, is adjusted to the response of the LQR-controlled Skyhook model. In order to improve the performance of the suspension, the control force of the actuator in the Macpherson model is obtained by the sliding mode control method, via changing the order of the sliding surface equation. It has been proven that as the system response is optimized in the same way as that of the Skyhook template model with the LQR controller for various road disturbance functions.

Power Factor in Control Lyapunov Functions For Electrohydraulic Tracking Problem under The Influence of Friction

2024-01-29T11:16:35+08:00

Control Lyapunov Function (CLF) is a powerful tool to synthetize nonlinear control laws. Several control laws may be deduced from only one CLF. In the Electrohydraulic ServoSystems (EHSS) literature, we distinguish two types of CLF especially for tracking control problem. The first type is a sum of a quadratic function of the errors while the second type is the quadratic function of the weighted sum of the errors. In this paper, we extend the second CLF type by adding a power factor in order to appreciate its influence in the closed loop performances. Hence, we obtain three clf instead of the initial quadratic function by varying the power 2, 4 and 6. The three deducing control laws are compared under the presence of friction. The numerical results show that the control law using the clf of order 2 has the best performances. Moreover, under the friction disturbance, the closed loop systems with the least order clf desmontrates the best robust results.

Exploring Magneto-Hydrodynamic Influence on Mixed Convection within a Vented Enclosure Containing a Heat-Conductive Square Column

2024-01-29T13:18:25+08:00

The heat transfer through mixed convection in obstructed cavities is essential in engineering applications. Magneto-Hydrodynamics (MHD) deals with electrically conductive fluids in a magnetic field. The vented cavities are receiving increasing interest in convection heat transfer (CHT), especially for complex flow patterns and MHD interactions. A vented square cavity (VSC) was considered in this study in addition to a two-heat-conducting horizontal solid square cylinder. The effect of MHD on mixed convection flow was numerically investigated using FlexPDE software. The study did not focus on specific values of parameters but rather tested a wide range, such as the Hartmann number of 10–30, the thermal conductivity solid/fluid ratio of 5–50, the Reynolds number of 100–500, and the Richardson number of 0-10. The isotherms, streamlines, average fluid temperature in the enclosure, and average Nusselt number were introduced. Findings indicated that the Hartmann, Reynolds, and Richardson numbers strongly impact the streamlines and isotherms, while thermal conductivity has a minor influence. Finally, the process parameters significantly affect the average fluid temperature and Nusselt number at the hot wall in the enclosure

Design of Magnetorheological Fluid Damper with Optimal Damping Force

2024-02-16T22:44:24+08:00

This article focuses on designing and analyzing of an optimal magnetorheological fluid damper (MFRD) having varying coil area shapes channeled into the piston of the MRFD. A finite element approach is employed to investigate the impact of piston material, coil area shapes, MR fluid gap and pole length on the generated magnetic field density, yield stress along with damping force. Taguchi L₁₈ orthogonal array was exercised for obtaining the optimal damping force. The ANOVA results investigates the contribution of the selected parameters and depicts that fluid gap is the most predominant factor which affects the damping force, making a contribution of 77.56%, followed by piston material which contributes 12.40%, pole length with a contribution of 8.23% and coil area shape has negligible contribution of 0.07%. Taguchi predicted the optimized model for selected parameters as A₂B₂C₁D₃ which is validated by carrying out the maxwell analysis. The damping force for the Taguchi predicted MR damper model is obtained as 1053 N, when 0.2 ampere current flows through the coil.

Trajectory planning, kinematics, and experimental validation of a 3D-printed delta robot manipulator

2024-02-16T22:46:31+08:00

This paper presents the implementation, trajectory planning, kinematics, and experimental validation of an open-source 3D-printed delta robot manipulator. The robot's hardware consists of three servo motors, an Arduino Uno microcontroller, and a PWM servo module. The software includes a trapezoidal velocity profile planner and an inverse and forward kinematics solver to calculate the motor angles required to achieve a desired end-effector position in task space. The 3D printed parts were obtained from an open-source Thingiverse project and assembled to form the robot's kinematic structure. The robot's performance was evaluated in terms of its accuracy, repeatability, and maximum speed for a pick-and-place task. Experimental results show that the robot can achieve a positioning accuracy of 2.2 mm, with a maximum speed of 0.4 m/s, 30 picks per minute, and load carrying capacity up to 200 g. These results are satisfactory considering the ease of assembly and the cost-effectiveness of the robot. The comparison of the calculated motor angles with actual motor angles obtained through additional potentiometer wires soldering shows promising results. The proposed robot's cost-effective characteristics, utilization of open-source 3D printing, and motion planning algorithms make it suitable for various applications, including education, research, and small-scale industrial applications.

Influences of Compression Ratio on Performance of Single Cylinder Otto Engine Using E50 Fuel

2024-02-19T09:59:27+08:00

Abstract—Ethanol mixed with a primary fuel is a promising alternative fuel. To increase performance, an optimal compression ratio must be set. The compression ratio is the ratio of the maximum volume divided by the minimum volume. Ethanol-gasoline mixtures have high octane and can be used in high-compression engines. This research aims to identify how changes in compression ratio can affect various aspects of engine performance, including torque, power, fuel efficiency, and thermal efficiency. This study is expected to reveal new insights that can aid in optimizing engine performance and developing a more comprehensive understanding of the characteristics of the E50 fuel within the context of Otto engine usage. A single-cylinder Otto engine was used for testing. Compression ratios of 9.3:1, 10.3:1, and 11.3:1 were tested. The results showed that the compression ratio of 9.3:1 produces a peak torque of 7.17 N∙m, peak power of 3.36 kW, lowest BSFC of 0.275 kg/kWh, and highest BTE of 37.49%. A compression ratio of 10.3:1 produces a peak torque of 7.21 N∙m, peak power of 3.57 N∙m, lowest BSFC of 0.281 kg/kWh, and highest BTE of 39.46%. A compression ratio of 11.3:1 produces a peak torque of 7.73 N∙m, peak power of 3.81 kW, lowest BSFC of 0.275 kg/kWh, and highest
BTE of 40.36%. Compared with pertalite, E50 reduces torque by 9.25%, power by 9.93%, BSFC by 3.66%, and BTE by 8.76% at all compression ratios.

Empirical Modeling and Analysis of Process Parameters in Laser Beam Cutting Process

2024-02-21T13:58:07+08:00

The research has been originated based on the persuasive applications of Lasers in the field of various engineering industries i.e Aerospace, Automobile, Electronic and Heavy manufacturing industries to machine a variety of metals and alloys. Out of all the machining processes available, Laser Beam Machining is considered to be the best one, because of the following advantages i.e quick material removal, non-contact, non-wearing tool, involves highly localized heat input to the work piece, reduces distortion, and offers no tool wear, diminishes tendency of cracking. The present paper focused mainly on developing the empirical relationships between the input process parameters and the output responses in LBC process. Laser power, Cutting Speed, Gas pressure and Focal distance are the input process parameters. The output responses considered are related to the quality of cut. Surface roughness is the first output responses considered and the second one is Burr height. Total number of experiments carried out are 27 based on the Taguchi DOE. Hastealloy C276 is the work material. Response Surface Methodolgy is applied for the Experimental data of 31 samples to derive the empirical relationships. Later ANOVA analysis is also carried out to check the adequacy of the derived equations. Based on the ANOVA analysis, the models are classified as significant or nonsignificant. Further the significant models can be used for optimizing the Laser beam cutting process.

The Effects of Machining Parameters on Total Cutting Force in Hard Turning Process of Hardened 90CrSi Steel Using Carbide Insert with MoS2 Nanofluid MQL

2024-02-26T09:51:57+08:00

Hard machining is being widely used, although there are many problems such as cutting forces and cutting heat generated during the machining processes. The use of suitable cooling lubrication conditions is an important factor and has a great influence on the machining efficiency and surface quality in hard machining. Among the proposed technology solutions, minimum quantity lubrication (MQL) using nanofluid is a new and proven effective solution for hard turning. Considering these data, the machinability of 90CrSi steel with carbide inserts was evaluated using nanofluid with different concentrations (1%, 1.5% and 3%) of molybdenum disulfide (MoS₂) nanoparticles in emulsion oil. Box-Behnken optimization experiment design and ANOVA analysis were used to study the influence of input parameters and determine optimal values. The results present the effect of the survey parameters and provide technical guidance for specific objective functions for further sustainability studies on MQL hard turning using nano-cutting oils. A mathematical model was also used to predict the total cutting force value in the hard turning process under MQL conditions using MoS2 nanofluid. The obtained results indicate that the total cutting force reached the minimum value (328 N) with the MoS2 nanoparticle concentration of 1.985%, a cutting speed of 80 m/min, and a feed rate of 0.138 mm/rev. In particular, the work has also provided technical guides for different machining conditions.

Failure Analysis of S55C Medium Carbon Steel for the Pickup Crankshaft

2024-02-26T09:54:10+08:00

There have been reports from service centers of important problems of a diesel engine crankshaft in mini trucks. All crankshafts crack from the same region, the fracture occurred in the first crankpin of the crankshaft. The crankshaft is made from JIS-S55C hardened medium carbon steel. A series of experiments including chemical analysis, macro and microstructural analysis, mechanical properties test, and numerical stress analysis. The results of fracture surface of this crankshaft were cause by fatigue with the detection of beach marks, ratchet marks, river marks, cleavage fracture and fatigue striations which these results indicate that the fracture mode of brittle fracture. The microstructure is composed of perlite-ferrite on the outer surface showed some coating nitriding layers, most hard coating is not found, the hardness test revealed an uneven hardness distribution, the maximum hardness on the center of the shaft measuring 309 HV, which is more than compared to the outer surface is 259 HV for these applications. It was found that the hardness value was abnormal. This is consistent with the experimental results of the surface microstructure which showed some coating layers, while the hard coating is not found. Besides, the numerical results also revealed that the first crankpin fillet was the most vulnerable to breakage, which is consistent with the mechanical experimental results. Finally, the summary analysis results are consistent with the hypothesis of this research and as an information for a prevent such failures crankshaft in the future.

Leisure Boat Concept Design: Study on the Influence of Hull Form and Dimension to Increase Hydrodynamic Performance

2024-02-26T15:54:24+08:00

The tourism sector contributes significantly to the economic growth of the community and the country. Labuan Bajo has the potential for marine tourism which is famous to foreign classes. The separation of the islands in Labuan Bajo requires transportation to support tourist activities to tourist destinations. One type of transportation to support the needs of marine tourism is leisure boats or recreational boats. Recreational boating has become popular in many developed coastal countries and contributes to their economy. The tourist ship must have safety standards for passenger safety and efficient operational costs. In a study in the Turkish Aegean Sea, the type of vessel that had the most accidents was yacht/leisure vessels. A leisure ship that functions optimally is needed, so research on the hull's hydrodynamic characteristics is essential. This research aims to find the effect of hull type shape and main size changes on the hydrodynamic characteristics of the ship. This research will look for the factors that most influence these changes. Our research method is to design and analyze 12 hull model variations based on five reference ships. The variation in the boat's main dimensions comes from the regression method calculation. The results of resistance, stability, and seakeeping performance are analyzed. We ranked the simulation analysis results based on the multi-attribute decision-making method. Furthermore, we conducted a sensitivity analysis of all simulation results of model variations to determine the most significant influence factors. The results show that the shallow v hull shape gets the best score for leisure boat needs. The hull shape factor significantly affects the ship's resistance value, while the size factor has more influence on the ship's stability.

Development of Deep Learning for Power Energy Optimization in the Industrial Robot System

2024-01-08T16:56:01+08:00

Joint friction, torque, current and power consumption of robot industry extremity are significant technical indicators of the capability of each robot instruction. In this paper, the identification parameters of each articulation can be quantified via machine learning and deep learning technic. This power consumption modeling and optimization is driven by Nonlinear Least Squares (NLS) and Scaled Conjugate Gradient (SCG) estimation. The simulations and experiment rely on the assigned dynamics profile motion to control six joints robot in which each joint robot parameter was identified and measured. The robot parameters were investigated in dynamic response in the experiment, and the power consumption estimation using NLS and SCG was analyzed. The results showed an exact prediction of dynamic parameters and the overall power consumption of robot instruction with NLS maximum error is 3.49 W or 4.98%, SCG maximum error is 1.56 W and 2.29% and RMSE maximum error is 2.39 W or 3.41%.

Fracture Analysis of S45C Medium Carbon Steel for the Van Front Drive Shaft

2024-01-25T10:54:11+08:00

In this study, the drive shaft failure mode in a van is investigated by evaluation of the macroscopic and microscopic morphologies of the fracture surface, chemical composition, metallographic analysis, mechanical characteristics of the material, and drive shaft fatigue test. JIS-S45C hardened medium-alloyed steel is used to make the drive shaft. The failure mechanism for this drive shaft was mixed, which means that it was a combination of both brittle and ductile fracture. This is evident in the central interior region of the drive shaft. The summary result of this drive shaft is fracture surface was that fatigue was the cause of it, and fatigue was the dominant mechanism of drive shaft failure due to obvious beach marks at the fracture surface and dimples at the central region. The shaft surface has a maximum hardness of 300 HV, while its center axis has a minimum hardness of 214 HV. Additionally, the results of the R.R. Moore fatigue life assessment were compared with the outcomes of the numerical simulations performed using the ANSYS program. It was found from the fatigue experiment that the S-N Curve shows that fatigue life increases when the stress level acting on the test piece is reduced. It was discovered that the ANSYS assessment rate was a respectable 5% higher than the trial rate. The results of recommending materials used to make shafts for all 4 types found that Total Deformation for AISI 5140 Steel is less when compared to other three materials.