Comprehensive Analysis of a Tricycle Structure with a Steering System for Improvement of Driving Properties While Cornering

Abstract

This paper focuses on the development, theoretical and experimental research on the structural units of an unconventional three-wheeled vehicle. The vehicle is designed in order to increase the stability when cornering in a low curvature radius. Current research work describes solutions to increase the cornering stability of either conventional three-wheeled vehicles or, more rarely, unconventional vehicles designed on the basis of complex wheel-tilting mechatronics. Thus, there is a gap in research in respect of consideration of a stability-enhancing mechanism for three-wheeled vehicles based on a combination of tilting and deflection of the front steered wheel in the course of cornering. This paper then compares the stability of a three-wheeled vehicle with one steered wheel in front and two wheels in the rear (1F2R) in conventional and unconventional designs. A particular linear formula for the stability of the three-wheeled vehicle in cornering is derived. This study further deals with the design of the frame intended to hold the unconventional steering mechanism of the front wheel of the vehicle, on the one hand, from the theoretical integrity point of view using CAD-, FEM- and MBS-based software and, on the other hand, from the experimental point of view by determining the multiaxial fatigue life of the test specimens. These were made from the frame structural material and loaded with an equivalent load (bending-torsion) corresponding to the real load of the frame in operation. It was discovered that the designed patented front wheel steering mechanism increased the passing speed by 19% in comparison with a conventional vehicle at the minimum possible radius of a corner. The designed vehicle meets the safety conditions in terms of frame integrity and load-bearing capacity. The vehicle frame is designed with respect to the fatigue life of the material, the results of which are presented in the work. The material employed for manufacturing the frame is aluminum alloy type EN AW6063, which makes the frame lightweight and strong.

Utilizing Dynamic Analysis in the Complex Design of an Unconventional Three-Wheeled Vehicle with Enhancing Cornering Safety

“…Since the project itself embodies the concept of a "green vehicle" (aiming to reduce fuel consumption and CO 2 emissions [17,18] and employ electric propulsion), it was decided to utilize a commercial aluminum alloy, EN AW6063, as the construction material for the frame. This strategic decision resulted in a weight reduction of the frame by up to 40 kg when compared to the parameters of a similar vehicle, the Kyburz Classic (Figure 2) as mentioned in [7]. Moreover, the lowering of the frame's center of gravity by 0.15 m has a positive influence on stability by reducing the destabilizing moment caused by centrifugal force.…”

“…A comparison between four-wheeled and three-wheeled vehicles leads to the conclusion that four-wheeled vehicles exhibit better stability [5,6]. The reduced stability of three-wheeled vehicles, when considering the same geometry (track width and center of gravity height), is attributed to the lower perpendicular distance from the vehicle's weight (mass) to the axis of rollover (connecting the front and rear wheels) compared to a four-wheeled vehicle [7]. This understanding led to the development of a new front-steered wheel suspension system (Figure 1b) that allows for both wheel displacement and rotation, thus increasing the lever arm of the gravitational force and consequently the stabilizing moment.…”

“…This understanding led to the development of a new front-steered wheel suspension system (Figure 1b) that allows for both wheel displacement and rotation, thus increasing the lever arm of the gravitational force and consequently the stabilizing moment. The approach to achieving the desired mobility capabilities was published by the authors in [2,[7][8][9]. This represents the second step in the process of theoretical improvement.…”

“…The final design proposal for the frame is preceded by a substantial effort invested in determining the physical properties of the construction material. The authors addressed this issue through extensive research described in detail in [2,7,8,19]. The yield strength of the EN AW 6063 material was experimentally determined using a tensile test, resulting in an average value of 247 MPa.…”

Determining the load on a body of the gondola car with unloading hoppers under the basic operating modes

“…Prospects for the development of the economy of Eurasian countries predetermine the increase in the efficiency of operation of the transport industry [1,2]. To ensure the profitability of the transport industry, it is important to update it with vehicles with improved technical and operational performance [3][4][5].…”