Vehicle Body Research Articles

Effect of Electrode Type and Weld Current on Service Life of Resistance Spot Weld Electrode

HSLA steels are widely preferred in the automotive industry due to their advantages of high strength, lightening of vehicle weight and formability. The fact that a lot of welding processes are carried out during the creation of the vehicle body has made the welding operations of these steels an important topic. In this study, zinc coated HX340LAD+Z sheet material was welded by RSW application in factory conditions. The welding opera-tion was carried out with different current intensities and 300 spot welds for three different electrodes, keeping the weld duration constant. After the welding trials, the shortening of the electrodes was examined and information about the electrode lifetime was obtained. The weld core diameter was measured on the sheet metal also microstructure and micro-hardness investigations were made. As a result of the findings, information was obtained about weld hardness and collapse. Determination of splashing in the HX340LAD+Z ma-terial was provided by SEM imaging and EDX studies. It was determined that F type Copper electrode was more efficient.

Water-exit impact of deep-sea mining vehicles: Experimental and numerical investigations

The operation of the deployment and retrieval system of a deep-sea mining vehicle (DSMV) is closely related to its water exit process; rapid water exit processes under wave conditions tend to exert negative influences on the safety and reliability of the entire system. To evaluate the specific effect of the interaction between the DSMV and the surrounding seawater, computational fluid dynamics (CFD) was used to predict the hydrodynamic characteristics and water-exit impacts of the DSMV at different retrieval speeds. First, a stokes-wave-free surface based on an overset mesh method integrating the volume of fluid (VOF) method was developed to reproduce level 4 sea conditions. Subsequently, the water surface deformation and water resistance were recorded to verify the proposed numerical method. These numerical and experimental findings indicate that when a vehicle body passes through wavy water at a relatively high speed, its lifting cable experiences a water-esistance force that is several times its weight. Finally, a vehicle body with a small retrieval speed might undergo several wave cycles, resulting in its lifting cable becoming loose.

Load-bearing capacity of composite honeycomb sandwich high-speed train floor

ABSTRACT The honeycomb sandwich structure of composite materials has broad prospects for application in the lightweight design of vehicle bodies. This study investigated the influence of relative density and height on an aluminium honeycomb’s out-of-plane quasi-static compression performance through experiments and simulations. The accuracy of the carbon fibre/aluminium honeycomb sandwich panel’s three-point bending model is verified based on the Hashin failure criterion and experimental validation. Furthermore, the load-bearing capacity of the carbon fibre/aluminium honeycomb sandwich floor is analysed, and the factors influencing the load-bearing capacity of the floor are further explored. The results show that the relative density significantly impacts the out-of-plane quasi-static compression performance of aluminium honeycomb, while the height has a minor influence. Compared with the original CRH5-type floor structure, the carbon fibre/aluminium honeycomb sandwich floor has a weight reduction of 45.23%, and it meets the strength requirements under uniformly distributed and concentrated load conditions. Changing the honeycomb wall thickness and panel thickness distribution can improve the load-bearing capacity of the floor.

A new resistance insert spot welding method for injection-molded FRP–steel component

For weight reduction, multi-material designs comprising metal and fiber-reinforced plastic (FRP) components in vehicle body structures have been increasingly used. However, the commonly used resistance spot welding (RSW) technology for car body assembly cannot be employed to join sheet metal and FRPs, limiting the use of FRPs. To solve this problem, a novel resistance insert spot welding (RISW) technique was developed in this work for RSW of steel parts and FRP structure parts made by injection molding. Small inserts were developed by using finite element method and experiments that may be welded to different micro-alloyed and dual-phase sheet steels using the projection welding method. The usual flange width of original equipment manufacturers could be kept unchanged. Using the developed insert and welding parameters, the maximum temperature in the FRPs surrounding the inserts was limited to 255 °C, minimizing the damage to polyamide 6 (PA6) material (with 40 wt% glass fiber). A weldability range between 2.5 and 7 kA could be achieved. The joining strength of RISW between a micro-alloyed HC340 steel in 0.75 mm and 1.5 mm thickness and a 2.5 mm/3.0 mm PA6-GF40 material is 20 to 80% higher than self-piercing riveting (SPR). For high-speed loading, RISW strength increases by 39 to 56% further. Finally, RISW was successfully applied to an FRP–steel roof-frame sub-assembly that consists of 19 simultaneously integrated inserts, achieving 10% weight reduction.

Grey wolf optimization tuned drivetrain vibration controller with backlash compensation strategy using time-dependent-switched Kalman filter

To improve the performance and durability of vehicle components, efforts have been made to reduce driveline oscillations using advanced active control algorithms. However, existing methods often rely on subjective parameter adjustments, which can be burdensome for designers. This study introduces an effective tuning algorithm for a driveline vibration controller that accounts for nonlinear backlash effects. Initially, a driveline dynamics model is developed to focus on transient oscillations resulting from changes in driving force and the presence of nonlinear backlash. The backlash impact is incorporated into the model through a discontinuous dead-zone region. Two operational dynamics, which are the contact mode and the backlash mode, are considered. A dynamic output feedback [Formula: see text] controller is designed as a baseline controller to mitigate low-frequency resonance in the driveline. A solution for managing the nonlinear backlash challenges is introduced, involving the use of a simple control mode switching algorithm in conjunction with the controller. This algorithm relies on a time-dependent-switched Kalman filter. Additionally, the optimal settings for the parameters needed by the mode-switching algorithm are autonomously determined using the grey wolf optimizer (GWO). The proposed active controller can be implemented in real vehicles by using an on-vehicle acceleration sensor and electronic control unit (ECU). In a simulation environment, the vehicle body vibration is online fed back to the resultant controller, and an actuator is supposed to apply control commands to the driveline. The effectiveness of this newly proposed active controller is confirmed through comparative tests, revealing the superior vibration control.

Amplitude-Sensitive Single-Pumper Hydraulic Engine Mount Design without a Decoupler

Engine mounts serve three primary purposes: (1) to support the weight of the engine, (2) to lessen the transmitted engine disturbance forces to the vehicle structure/chassis or airplane fuselage, and (3) to limit the engine motion brought on by shock excitations. The engine mount’s stiffness must be high to control large engine motions and low to control chassis or vehicle body vibration. When hydraulic engine mounts are used, a device called a decoupler creates the dual stiffness requirement. However, numerous investigations have shown that the decoupler has the potential to rotate within its cage bound and become stuck or sink and obstruct fluid flow between the fluid chambers due to a density mismatch between the decoupler and the working fluid. In addition, most hydraulic engine mounts with a decoupler no longer act as vibration isolators but as hydraulic dampers. This study suggests a new amplitude-sensitive hydraulic engine mount design without a decoupler, where the vibration isolation of the engine mount is retained and there is a 75% reduction in the peak frequency, which further enhances the engine mount’s capabilities in comparison to the current hydraulic engine mounts with a decoupler. The new design concept and its mathematical model and simulation results will be presented.

Development of a novel nonrigid support friction stir welding repair robot for aluminum alloy train

PurposeThis paper aims to develop a specific type of mobile nonrigid support friction stir welding (FSW) robot, which can adapt to aluminum alloy trucks for rapid online repair.Design/methodology/approachThe friction stir welding robot is designed to complete online repair according to the surface damage of large aluminum alloy trucks. A rotatable telescopic arm unit and a structure for a cutting board in the shape of a petal that was optimized by finite element analysis are designed to give enough top forging force for welding to address the issues of inadequate support and significant deformation in the repair process.FindingsThe experimental results indicate that the welding robot is capable of performing online surface repairs for large aluminum alloy trucks without rigid support on the backside, and the welding joint exhibits satisfactory performance.Practical implicationsCompared with other heavy-duty robotic arms and gantry-type friction stir welding robots, this robot can achieve online welding without disassembling the vehicle body, and it requires less axial force. This lays the foundation for the future promotion of lightweight equipment.Originality/valueThe designed friction stir welding robot is capable of performing online repairs without dismantling the aluminum alloy truck body, even in situations where sufficient upset force is unavailable. It ensures welding quality and exhibits high efficiency. This approach is considered novel in the field of lightweight online welding repairs, both domestically and internationally.

PELATIHAN PEMBUATAN CAIRAN PENGKILAP MOTOR DI DESA NAGASARI

In an increasingly advanced development in this modern era, many people use vehicles, one example is motorbike vehicles, the increasing number of motorbikes makes some or a handful of people who do not take care of the motorbike body, because of this the motorbike body looks dull, so a Real Work Lecture (KKN) will be held in Nagasari Village, Serang Baru District, Bekasi Regency. This community service programme is carried out with the aim of training the community to make them aware of the importance of taking care of the washed motorbike body so that by washing the motorbike it looks clean and tidy. In its implementation, KKN participants used a training method that was carried out to the community in the form of making shiny liquid for motorbike bodies. Community service or youth has a positive impact, namely increasing knowledge and understanding of the importance of caring for the body of a motorbike and making motorbike body polish liquid so that the community or youth can be developed as a form of business, able to care for their own vehicle body.

The self-tuning fuzzy sliding mode control method for the suspension system with the LSTM network road identification

As an important component of semi-active suspension (SAS) systems, the built-in solenoid valve adjustable damper (BSVAD) is now widely used in the field because of its advantages of fast response, continuously adjustable damping, and lightweight design. However, only a few studies have discussed the BSVAD-modeling method. Hence, this study proposes a method for constructing an agent model using a feedforward neural network (FNN) for an equivalent BSVAD regulation mechanism. Meanwhile, a new control strategy, i.e., a fuzzy sliding mode control method based on road conditions (RC-FSMC), is proposed for calculating the required damping force. The proposed method identifies and analyzes unsprung mass acceleration characteristics using a long short-term memory network to obtain the road condition of the moving vehicle and inputs the output results into the designed fuzzy rules to adjust the sliding mode switching gain and finally realize road condition-based adaptive control. Finally, through simulation test analysis, the results show that the designed RC-FSMC strategy can effectively reduce vehicle body acceleration and vehicle dynamic load under different road conditions to improve the adaptability of the vehicle to different roads.

Technical operation factors influence on bus body durability

Introduction. The purpose of the work is to study the causes of corrosion destruction of bus bodies of the enterprise. In the course of work, it was revealed that the main causes of intensive corrosion destruction of bus bodies are insufficiently high corrosion resistance of metals used in the manufacture of the body frame. The main places of occurrence of foci of corrosion of the body are: wheel arches; rear and lower parts of the bus, which are more susceptible to adverse road conditions; the upper and lower parts of the window openings in case of violation of the tightness of the seal. In the course of the study, initial data were obtained to determine the conditions and factors determining condensation on the cooled surfaces of bus bodies entering the indoor parking area; a set of organizational and technical measures aimed at reducing the intensity of corrosion wear of the company’s vehicle bodies was developed.Materials and methods. The results of observations of changes in the technical condition of bus bodies, parameters of their maintenance conditions were used, methods of a priori ranking of factors and classification were used. The results and recommendations on the technical operation of bus bodies are described.Results. As intermediate results of the conducted research, the data on the influence of the technical condition of bus bodies on the indicators of technical operation were obtained, which make it possible to justify the modes of maintenance and storage of motor vehicles. The data obtained make it possible to simulate the processes affecting the technical condition of bus bodies, which is the basis for the development of optimization measures.Discussion. It is noted that the approach implemented during the study enables to establish a set of factors affecting the technical condition of bus bodies, and to determine the consequences of premature achievement of the limit state by the elements of the load-bearing structure.Conclusion. As a generalizing conclusion, it is noted that the practical implementation of the developed methodology ensures the development and implementation of sound measures to increase their durability in the practical activities of road transport enterprises.

Identification and sensitivity analysis of vehicle body compound vibration

Identification and sensitivity analysis of vehicle body compound vibration

Analysis of longitudinal-vertical coupling vibration of four hub motors driven electric vehicle under unsteady condition

The influence of hub motor unbalanced magnetic force (UMF) on the vibration of electric vehicle under steady state conditions has been known, but under unsteady conditions, the hub motor UMF will change with the vehicle operation condition, and there would exist complex coupling vibration for the hub motors driven electric vehicle. Here, the longitudinal-vertical coupling dynamics of the four hub motors driven electric vehicle under unsteady condition is studied. Integrating the motor electromagnetic excitation and electric vehicle dynamics, a longitudinal-vertical coupling dynamics model of the four hub motors driven electric vehicle is established. Based on the variable switching frequency field-oriented control model, analytical model of the UMFs acting on the motor stator and rotor parts under unsteady condition are developed. For model validation, a four hub motors driven electric vehicle has been tested, the accuracy of the longitudinal-vertical coupling dynamics model established in this paper was verified. Then, longitudinal-vertical coupling vibration characteristics of the four hub motors driven electric vehicle under road excitation and coupling excitation are analyzed. The results show that the longitudinal and vertical movement of the four hub motors driven electric vehicle is coupled by hub motor. In addition, under unsteady condition, the motor UMFs will cause vertical vibration of the electric vehicle body and hub motor stator, the vibration shows order characteristics including low order harmonic hfc and inverter switching frequency sideband harmonic k1 fs±k2 fc ( fc = pn/60, fs is inverter switching frequency, k1 and k2 are positive integers, p is the number of pole pairs and n is motor speed.). The motor electromagnetic torque will cause longitudinal vibration of the electric vehicle body, the vibration shows order characteristics including harmonics fs±3 fc and 2 fs. The main harmonic of vehicle body pitch angle acceleration is 2 fs.

Nonlinear model predictive control for trajectory-planning and tracking based on tilting technology to achieve vehicle obstacle avoidance

ABSTRACT High-speed autonomous vehicles can effectively improve the performance of obstacle-avoidance trajectory-planning and tracking control through integration with existing electronic control systems. However, relatively little research has been conducted in this field. This paper proposes a novel methodology of obstacle-avoidance trajectory-planning and tracking control based on active front-wheel steering integrated with tilting technology that can tilt the vehicle body toward the inside of the curve via active suspension when turning. The controller is designed using hierarchical control, in which the upper layer uses the point-mass vehicle model to design the trajectory-planning algorithm based on model predictive control. The lower layer uses the nonlinear vehicle model to design obstacle-avoidance tracking nonlinear model predictive control based on active steering integrated with tilt control. Then, the constrained nonlinear model predictive control problem is transformed into a constrained nonlinear programming problem, which is solved by sequential quadratic programming. Finally, simulations were performed using the CarSim/Simulink co-simulation platform. Two other hierarchical obstacle-avoidance tracking nonlinear model predictive controllers were designed as comparison objects. The simulation results show that the planning trajectory of the proposed integrated controller is closest to the obstacle. This controller effectively improves the vehicle obstacle-avoidance trajectory-tracking performance, handling stability, and maneuverability.

Modelling and performance analysis of free body dynamics of electric vehicles

The modelling and performance analysis of free body dynamics in electric vehicles (EVs) plays a crucial role in understanding and optimizing the vehicle's behavior and performance. This research focuses on accurately modelling the forces and motions acting on the vehicle body, excluding the powertrain components. By considering factors such as vehicle weight, suspension characteristics, tire properties, and aerodynamic forces, a comprehensive mathematical model is developed. This model enables the simulation and analysis of the vehicle's behavior under various operating conditions. The performance analysis involves evaluating key metrics such as vehicle response, stability limits, and ride comfort. The proposed system is compared with the existing electric vehicle in the market. The findings from this research contribute to the design and development of EVs with improved handling, stability, and energy efficiency. Additionally, they inform the development of advanced driver-assistance systems (ADAS) and autonomous driving technologies. Overall, the modelling and performance analysis of free body dynamics in EVs supports the advancement of sustainable and efficient transportation systems.

Simulation Study on the Influence of Grain Operation Conditions on the Dynamic Characteristics of Vehicle Body based on RecurDyn

At present, the grain storage depot has introduced the warehouse closing vehicle to replace the manual grain surface leveling operation. Aiming at the problems of subsidence, vibration and slipping when the warehouse car walks on the grain surface, the multi-body dynamics simulation is carried out for the four complex working conditions and load conditions of the car body in the grain depot environment, including straight running, turning, tilting and obstacle crossing, and its driving dynamic characteristics are analyzed. It can be seen from the simulation results that in the turning condition, the required driving force is the largest, the sliding condition is the most serious, the sinking degree is the deepest, and the stability is the worst. The driving dynamics of the clearance car will change suddenly when entering and leaving the pit under the obstacle crossing condition. Through the dynamic simulation results, the change law of the driving dynamic characteristics of the clearance car is summarized, and the vibration damping performance, adhesion performance and Through performance and work efficiency, it provides a theoretical basis for vehicle body design and optimization.

Application of hybrid control algorithm on the vehicle active suspension system to reduce vibrations

This research proposes a hybrid control algorithm to enhance smoothness in a vehicle’s motion. The control signal is synthesized from two separate controllers, Proportional Integral Derivative (PID) and Sliding Mode Control (SMC), to achieve superior control performance. The novelty of the proposed control algorithm lies in using a double-loop algorithm to determine the controller parameters. The algorithm proposed in this research involves two computational processes to determine the model’s optimal values including the raw value and the acceptable value. The proposed control algorithm has been simulated considering three specific cases corresponding to the three types of road stimuli. The results demonstrate that the values of sprung mass displacement and acceleration dropped considerably with the application of the proposed algorithm. Moreover, the change in vertical force at the wheel is also reduced with the application of the algorithm particularly in the third case where the vertical force at the wheel has reached to zero. The average values of vehicle body displacement are found to be 166.17 mm (for passive case), 54.20 mm (for PID), and 42.52 mm (for SMC). The proposed control algorithm managed to reduce this value to 8.95 mm as evidenced by simulation results. Finally, the response of the control system when subjected to an excitation signal from the road surface further demonstrates efficacy of the proposed hybrid control algorithm.

Particularities regarding the design and conception of a bodywork superstructure intended for the transportation of perishable goods

The aim of this paper is to present the characteristics of the design and construction of a vehicle body superstructure intended for the transportation of perishable goods. In the first phase, the design of the superstructure was conceived, followed by its design. Then, the calculation of the mass distribution on the truck axles, as well as the calculation of the truck’s cornering, was carried out, and finally, the superstructure was made, which was mounted on the truck.

Impact load identification of high-speed train scale carbody based on multi-objective optimisation and TwIST sparse regularisation

ABSTRACT Effective identification of dynamic loads on vehicle systems is crucial for evaluating the structural integrity of railway vehicles. The inverse problem method has been proposed for dynamic load identification to determine the impact load on the carbody. Due to the sparse nature of the impact load, the combination of the l 1-norm and TwIST (two-step iterative threshold shrinkage method) methods is used to reconstruct the impact load, taking into account the influence of sensor placement on the identification results. The MOHBA (Multi-objective Optimisation Honey Badger Algorithm) was proposed to simultaneously select the regularisation and iteration parameters. This algorithm aims to improve the accuracy of subsequence load reconstruction by considering the influence of noise levels when selecting the measured data. The impact load experiment was conducted on the scale carbody, and the single-point impact load and multi-point impact load matched well with the actual load. Satisfactory load identification results can still be achieved when the noise level is within 15%. When arranging measurement points on the boundary of the vehicle body, satisfactory load identification results can also be achieved.

Experimental and Numerical Analysis Over Power Series Nose Cone

While designing aerospace vehicles, one of the most important factors to consider is drag. Drag force opposes the vehicle and causes it to slow down, which in turn requires more fuel to maintain flight. The vehicle nose cone plays a vital role in minimizing the drag during flight. The shape of the vehicle's body, as well as the fluid characteristics and orientation, can all have a significant impact on drag. To determine the most effective nose cone design, a study was conducted to test the aerodynamic performance of power series nose cone profiles using both experimental and computational techniques. All nose cone profiles with the same L/D ratio were assessed at 25 m/s speed with no angle of attack. The experimental data, including pressure, velocity, and drag, were then compared with computational data to ensure the accuracy of the wind tunnel experiments. The primary factor in determining the best shape for the subsonic flow range among all the nose cone profiles was the drag coefficient. The nose cone with a power of 0.25 was found to have the lowest drag coefficient at low subsonic speeds, making it the best-performing nose cone profile among those investigated. During take-off, drag is the most undesirable factor, as it can significantly impact the fuel efficiency of the vehicle. Therefore, it is crucial to have the least amount of drag possible. In this case, the nose cone with a power of 0.25 can be used in the initial stages of the rocket to minimize drag and maximize fuel efficiency.

Analisa Kekakuan Pelat terhadap Pembentukan Dimple Dies dengan Variasi Diameter Lubang dan Jumlah Lubang Dimple

The construction of the body of minibus passenger vehicles usually uses walls, roofs and floors called vehicle panels. The vehicle panel itself is the most important part that supports safety and comfort for the occupants of the vehicle. Generally, the vehicle panel will cause a sound that makes passengers uncomfortable because of the noise that occurs due to the vibration of the vehicle engine and damaged road conditions. Excessive vibration can be reduced by increasing the rigidity of the panel by changing the shape such as beads, embossing, stiffeners, spot welded stiffenes, and grooves. The purpose of this study was to determine the effect of borehole variation and the number of dimple holes on plate stiffness for its natural frequency response. This research method is shown as follows: making experimental designs, dimple manufacturing processes, measuring and analyzing the results of dimple-shaped plates with variations in boreholes and the number of dimple holes to stiffness for their natural frequency response response. Based on the results, the number of holes on the dimple plate affects the stiffness of the plate to its natural frequency response.