Scientific Journal of Silesian University of Technology. Series Transport

8

Authors: Elżbieta MACIOSZEK

During the transportation of goods, damage and destruction of the transported cargo constitute a very large part of the damage. The most common direct cause of damage is an improper arrangement and securing of the transported load. An improperly secured load may pose a threat to the transporters and bystanders. Incorrectly secured loads can fall from the vehicle, obstruct movement, and cause injury or death. In addition, improperly secured loads can cause injury or death in heavy braking or a collision. The way the load is distributed and secured on the vehicle can negatively affect driving behaviour, making it difficult to control the vehicle. This article presents the conditions related to the transport of loads in road transport, describes both the forces that act on the load during the journey of a vehicle and the most important techniques for securing loads in road transport.

9

Authors: Nodira SOATOVA

This article presents the results of the analysis of experimental data on testing of reinforced concrete elements for multiple-repeated loads and field tests of operated span structures. This article proposes dependencies on the definition of deflections during the operation period. Based on the processing of the available experimental data, dependences are proposed for determining deflections under multiple repeated loads, and on this basis, dependences are obtained for predicting the residual life of span elements. The initial data for the calculations are the data on the accumulated residual deflections determined in the process of technical diagnostics.

10

Authors: Silvia MALÁKOVÁ

In practice, gear units whose transmission number is not constant during one revolution are used. Such gears include the proposed elliptical transmission. Its application can be (missing a word?) and the automotive industry. The gears set consists of a pair of identical elliptical gears. The transmission ratio of the designed elliptical gear is not constant. The basic kinematic characteristics of this transmission are described in this work. The deformation in contact point of non - circular gears is determined by the finite element method in this paper. The results are compared with the deformation of the teeth of the spur gears.

11

Authors: Ján DIŽO, Miroslav BLATNICKÝ, Paweł DROŹDZIEL, Stanislav SEMENOV, Evgeny MIKHAILOV, Jakub KURTULÍK

The lorry frame is the main carrying part of a lorry, composed of several components. These components are connected by joints into one structural unit and it forms the lorry chassis. The contribution of this article is focused on the strength analyses of a backbone frame, which is used on an off-road lorry chassis. Strength analyses are carried out utilising the finite element method. This article presents a created three-dimensional model of the frame and definition of boundary conditions (loads, the definition of degrees of freedom) needed for simulation computations. Results of the numerical calculations are the main parts of this article. Attention is mainly centred on the distribution of stresses of the frame under defined loads and its deformations.

12

Authors: Mikhail ZHILEVICH, Sergey ERMILOV, Denis KAPSKI, Yuriy VOVK, Oleg LYASHUK, Iryna VOVK

The design dimensions of the executive hydraulic cylinders of the brake system of heavy-duty mining dump trucks cause high fluid flow during the braking process. Therefore, dimensions of the anti-blocking system modulator spool pair require unique electromagnets or hydraulic amplifiers to control. These solutions do not allow the required modulator performance. Thus, a modulator scheme with a division of the flow of fluid from the source to the brake cylinders was developed. This scheme allows during emergency braking passing, an additional amount of fluid to cylinders through the valve, installed parallel to the main valve upon pressure increase phase and controlled by the pressure difference. The task is to develop a method for calculating the main structural dimensions of a modulator. The calculation of the valve of the second cascade, installed in parallel to the main stage, is carried out for the emergency braking mode with the maximum flow rate to ensure the required performance of the braking system. The balance of fluid flows equations is compiled at the key points. The flow rate of the fluid through each of the valves is determined by the Torricelli formula, and the pressure difference across the valves is assuned equal. The obtained relations allows building a family of Q-p curves, which can be used to select the diameter and stroke of the additional valve depending on the flow rate in the brake system.

13

Authors: Ladislav ILLES, Martin JURKOVIC, Tomas KALINA, Piotr GORZELANCZYK, Vladimir LUPTAK

Increasing transport volumes on Europe's inland waterways is a major reason for improving the quality and reliability of internationally important waterways. Continued navigation restrictions due to restricted draft (draught) led to the search for new design solutions. Such solutions enable navigation even under critical navigation conditions. Restricted draft is one of the most important limitations that hinder navigation, especially in the summer. The main objective of the construction of an inland vessel is to obtain a shape that will achieve optimum performance with as little resistance as possible. A shape that will be able to navigate at a limited depth. Presently, there is no clearly defined methodology as a procedure for optimising the hull. When solving theoretical problems of shipbuilding character and ship calculations, it is necessary to consider the basic theory of the ship with special regard to the latest methodological procedures of related scientific disciplines. This paper presents a methodology that considers all the basic aspects of optimisation tasks in ship design and construction.

13

Authors: Dahlen SIQUEIRA SILVA, Csaba CSISZÁR, Dávid FÖLDES

Discussions on how urban space would be transformed by the use of autonomous vehicles (AVs) are scarce. This study identifies the impacts caused by the shared use of AVs on urban parking and urban space management. An estimation method was formulated considering the reduction in parking demand, the possible alteration in vehicle ownership, and the reallocation of urban space. A case study was performed in a 673,220 m2 area through scenarios created by using real data of parking spaces and the results of previous studies. Results showed that parking spaces can be saved with the use of shared AVs, which would allow the reallocation of urban space to new uses (for example, implementation of around 12,000 bike-sharing docking spots, 10 km bike lanes, 7 km additional traffic lane or 140 ‘parklets’). The results contribute to revealing the positive impacts of AVs.

16

Authors: Greg WHEATLEY, Samuel POPOOLA

Investigation on a designed and modified standard automatic transmission for a 2017 Yamaha Grizzly All-Terrain Vehicle was carried out to allow it to be controlled remotely and autonomously while maintaining its ability to be manually operated. The vehicle is a part of a project named AutoWeed. This project aims at developing a vehicle which can be used in the Australian outback to control and eradicate weeds. Preliminary tests were conducted on the vehicle to determine the performance parameters required to replace the movement supplied by the operator. Several devices used to achieve this motion were explored. It was concluded that the Motion Dynamics HB-DJ806 - LALI10010 electromechanical linear actuator be used as a proof of concept device for this application. This device is capable of exerting 200 N at 35 mm/seconds. It has a stroke length of 50 mm and was powered by a 12V DC motor, which drew 3 amps at maximum load. Through testing, it was found that the selected actuator did not have enough stroke length to cycle through the five gears on the ATV. This error was rectified allowing the system to function as intended. To achieve a reliable design, however, the Linak LA14 actuator was purchased as a final design as it was stronger, faster and had feedback capabilities. Before procurement, the new actuator was digitally modelled using SolidWorks 2017 and 3D printed to confirm the mounting position and method. An ANSYS FEA was conducted on all the custom-made components including the actuator bracket and mounting plate to ensure reliability. The bracket model was manufactured using 3D printing from ABS. It was recommended that for reliability, the bracket should be constructed from a stronger material such as aluminium. The results gained from testing proved that the autonomous transmission system implemented was reliable and repeatable. This was justified as the system achieved a 100% success rate when cycling through gears.

18

Authors: Olorunfemi Ayodeji OLOJEDE

Over two-thirds of greenhouse gases (GHG) emissions that contribute to climate change emanate from transport. This could double by 2050. With per capita emissions nearly twice the global average, South Africa ranks 13th globally on GHG emissions with road transport, directly and indirectly, accounting for 91.2% of total transport GHG emissions. It has been projected that by 2100, up to 100% increase in the country’s average temperature above the 20th century average rise. This has far-reaching implications, even for the transport sector. To decarbonise its transport sector, South Africa has committed to reducing its GHG emissions by 34% by 2020 and 42% by 2025, respectively, through pointed strategies and policies. However, efficient implementation of proposed measures and sufficient funding remain daunting challenges. Thus, this paper contends that adequate attention has not been paid to active transport in the country’s transport decarbonisation policy implementation despite its inclusion in policy statements. It then asserts that active transport is indispensable to South Africa’s achievement of its transport decarbonisation goals, especially when steps taken hitherto seem ineffective. Consequently, the right attitudes, regulatory instruments, and policy initiatives towards the promotion of active transport are recommended.