SV-JME is indexed / abstracted in:

  • SCI-Expanded,
  • Compendex,
  • Inspec,
  • ProQuest-CSA,
  • SCOPUS,
  • TEMA, ...
The list of the remaining bases, in which SV-JME is indexed »

Editorial Office

University of Ljubljana
Faculty of Mechanical Engineering
Journal of Mechanical Engineering

Aškerčeva 6,

SI-1000 Ljubljana
Slovenia

P: +386 1 4771 137
E: info@sv-jme.eu



The journal is subsidized by Slovenian Research Agency.

 
ISSN: 0039-2480

Journal of Mechanical Engineering 63 (2017) 3

 

 

 


 

The Development of a Recognition Geometry Algorithm for Hybrid – Subtractive and Additive Manufacturing

Authors - David Homar* – Franci Pušavec


Abstract

In the last decade additive manufacturing of metal components has experienced enormous development. One of the most important achievements in this sector is the fact that nowadays it is possible to produce fully dense metal parts. Generally, additive manufacturing technologies are able to produce very complex geometries but are time and cost consuming for manufacturing of massive components. Machining technology, on the other hand, has the opposite characteristics. Both technologies, additive and subtractive, have advantages and disadvantages depending on the amount of material that need to be added or subtracted. The combination of these two technologies (i.e. hybrid manufacturing) results in a process where advantages of both technologies can be expected (cost, material consumption, etc.). Thus a novelty, the paper presents a development and analysis of software that analyzes the CAD model with geometry of the model and declares which part of model will be manufactured with machining and which will be produced by additive manufacturing. The software is evaluated on an industrial case from the field of injection mould inserts. Results show that such an automated algorithm decreases cost, better efficiency and nevertheless offer possibility to implement technology in industrial environment to improve manufacturing processes, i.e. in current case injection moulding process/technology.

Keywords - hybrid manufacturing, additive manufacturing, subtractive manufacturing, machining, conformal cooling channels

Paper's information
Strojniški vestnik - Journal of Mechanical Engineering 63(2017)3, 151-160, SI 23
DOI:10.5545/sv-jme.2016.3924

 

pdfThe Development of a Recognition Geometry Algorithm for Hybrid – Subtractive and Additive Manufacturing (.pdf 2.3MB)

 


  

Dynamic Model and Analysis of Nonlinear Vibration Characteristic of a Curve-Face Gear Drive

Authors - Zhiqin Cai – Chao Lin*


Abstract

To study the nonlinear dynamic characteristics of curve-face gear drive, a generalized nonlinear dynamic model based on Lagrange Bondgraphs was presented. The model considered the effects of the basic parameters of curve-face gear, such as meshing frequency, eccentricity k and the order number n1 of non-cylindrical gears. Utilizing this simulation model, the vibration characteristics of curve-face gears were analysed. It is indicated that the vibration response of the curve-face gear is more complex than that of the face gear due to the influence of external excitation. These characteristics determine that this gear pair cannot be applied directly to a transmission system with high speed. Finally, a related experiment was proposed to present the validation of the numerical model.

Keywords - curve-face gear, vibration response, limited speed, Lagrange bond-graphs, time-varying characteristics

Paper's information
Strojniški vestnik - Journal of Mechanical Engineering 63(2017)3, 161-170, SI 24
DOI:10.5545/sv-jme.2016.3859

 

pdfDynamic Model and Analysis of Nonlinear Vibration Characteristic of a Curve-Face Gear Drive (.pdf 2.0MB)

 


 

Efficiency Improvement of Agricultural Winch Machines

Authors - Martin Kodrič – Jože Flašker – Stanislav Pehan


Abstract

In this article the problems with the use of the common winch cart on very steep terrain planted with permanent crops are described, especially with regard to energy losses. A hypothesis is developed regarding the improved use of the potential energy that leads to the development of a new economical hydraulic machine. A transmission of the new agricultural tractor that can use the much bigger share of the effective potential energy is conceived in rough principles. A portable flatbed improves the total efficiency. A comparable analysis on very different sloped terrains is presented to argue for the greater efficiency of the new machine. The yearly fuel quantity saving by using the new hydraulic machine on the sloping terrain with realistic topography is 36 % in comparison to the winch cart. Decisional limits about the minimum internal combustion engine power are discussed.

Keywords - sloped terrain, permanent crop treatments, hydraulic tractor, crop treatment efficiency

Paper's information
Strojniški vestnik - Journal of Mechanical Engineering 63(2017)3, 171-180, SI 25
DOI:10.5545/sv-jme.2016.3968

 

pdfEfficiency Improvement of Agricultural Winch Machines (.pdf 2.8MB)

 


 

Modelling and Control of a Fixed Calliper-Based Electronic Wedge Brake

Authors - Fauzi Ahmad* – Khisbullah Hudha – Saiful Amri Mazlan – Hishamuddin Jamaluddin – Hairi Zamzuri – Zulkiffli Abd Kadir – Vimal Rau Aparow


Abstract

This paper presents a new design of an electronic fixed calliper-based wedge brake system. The movement of both sides of the brake piston is activated by a wedge block mechanism. The proposed fixed calliper-based electronic wedge brake system is a class of hydraulic-free device. The mechanism consists of two sets of wedge blocks, a ball screw drive shaft, a sliding beam and an electric motor. In this mechanism, the rotation of the shaft of the electric motor is converted into linear motion by using a ball screw drive shaft while the linear motion of the drive shaft will force the sliding beam to be displaced linearly. This will activate the wedge mechanism, which will cause the pad to be displaced tangentially to the disc brake. The movement of the pad in pressing the disc will generate clamping force and produce brake torque when the wheel rotates. In this study, the mathematical model of the system that generates the clamping force was identified. The model was based on a second order transfer function. The proposed mathematical model was then validated experimentally using a brake test rig installed with several sensors and input-output (IO) device. The performance of the brake mechanism in term of rotational input of the drive shaft and clamping force produced by the brake were observed. Accordingly, a torque tracking proportional–integral–derivative (PID) control of the system was proposed and studied through simulation and experiment. Comparisons between experimental results and model responses were made. It is found that the trend between simulation results and experimental data are similar, with an acceptable level of error.

Keywords - fixed calliper-based electronic wedge brake, clamping force system modelling and validation, torque tracking control, hardware-in-the-loop-simulation


Paper's information
Strojniški vestnik - Journal of Mechanical Engineering 63(2017)3, 181-190, SI 26
DOI:10.5545/sv-jme.2016.3508

 

pdfModelling and Control of a Fixed Calliper-Based Electronic Wedge Brake (.pdf 1.2MB)




Vehicle Aerodynamic Stability Analysis under High Crosswinds

Authors - Aleksander Grm* – Milan Batista

Abstract

In a strong crosswind, wind direction change may result in vehicle stability loss. This paper presents a numerical study of vehicle aerodynamic stability in a high crosswind situation. We start with a model explanation and introduce the complete computational fluid dynamics (CFD) framework used in the study. Important CFD parameters such as mesh type, turbulence model, and boundary conditions are exposed and discussed in detail. We demonstrate and discuss the flow structure around a simplified truck model. Results of the CFD analysis are compared to experimental data, showing an almost perfect match. The final CFD outcomes are functions of aerodynamic coefficients that depend on the apparent wind angle. Then, CFD results are used in the application of an aerodynamic stability analysis for the truck model. Finally, the critical stability bounds are calculated, showing the marginal crosswind driving properties of the vehicles.

Keywords - aerodynamic stability/ instability, computational wind engineering, overturning moments, computational fluid dynamics, wind-structure interaction

Paper's information
Strojniški vestnik - Journal of Mechanical Engineering 63(2017)3, 191-200, SI 27
DOI:10.5545/sv-jme.2016.4095

 

pdfVehicle Aerodynamic Stability Analysis under High Crosswinds (.pdf 1.0MB)




Determination of the Threshold for Extreme Load Extrapolation Based on Multi-Criteria Decision-Making Technology

Authors - Jixin Wang – Xinting Zhai* – Cheng Liu – Yingshuang Zhang


Abstract

The peak over threshold (POT) model is commonly used in extreme load extrapolation. Due to the important role that the threshold plays in establishing a POT model, a method to select the suitable threshold is designed based on multi-criteria decision-making (MCDM) technology. The mean deviation in probability distribution function, Kolmogorov-Smirnov test, and Chi-Square test are employed as the test criteria. An entropy method is applied to obtain the weight values of these tests. The VIKOR method is adopted to obtain compromise solutions according to the corresponding criteria and weight values. The POT requirement is used to determine a suitable threshold. The effectiveness and feasibility of this method are validated by the load time history measured in experiment and generated by simulation. A comparative analysis between this method and two other common methods is also conducted. The proposed method based on MCDM shows better performance.

Keywords - peak over threshold (POT), extreme load extrapolation, threshold, multi-criteria decision-making (MCDM), entropy method, VIKOR

Paper's information
Strojniški vestnik - Journal of Mechanical Engineering 63(2017)3, 201-211, SI 28
DOI:10.5545/sv-jme.2016.3557

 

pdfDetermination of the Threshold for Extreme Load Extrapolation Based on Multi-Criteria Decision-Making Technology (.pdf 842KB)

 


 


Leaflet SV-JME


 

 

Journal of Mechanical Engineering

in digital form


SV-JME-7-8-2017


SV-JME-6-2017


SV-JME-5-2017


SV-JME-4-2017

 

This web site uses cookies. By continuing to use website, you consent to install cookies on your device to access the site. More about cookies can be found here.