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With the growing prosperity of the long-distance freight and urban logistics industry, the demand for cargo trucks is gradually increasing. The connecting bracket is the critical connecting part of the truck chassis, which bears the load transmitted by the road excitation and reduces the damage to the frame caused by the load. However, the occurrence of rough road conditions is inevitable in heavy-duty transportation. In this paper, road durability tests and fatigue life analysis are carried out on the original structure to ensure the safety of the vehicle. Based on the known boundary and load constraints, a lightweight and high-performance structure is obtained through size optimization, as the original structure cannot meet the performance requirements. Firstly, the road test was conducted on the truck where the original bracket structure is located.

There are a large number of uncertainties in engineering design, and the accumulated uncertainties will enlarge the overall failure probability of the structure system. Therefore, structural design considering uncertainties has good guiding significance for improving the reliability of engineering structures. To address this issue, the dynamic-static structural topology optimization is established and reliability-based topology optimization with decoupling format is conducted in this study. The design point which satisfying the constraint of the target reliability indicator is obtained according to the reliability indicators of the first-order reliability method, and the uncertain design variables are modified into a deterministic variable according to the sensitivity information.

Lightweight design is a key factor in general engineering design practice, however, it often conflicts with fatigue durability. This paper presents a way for improving the effectiveness of fatigue performance dominated optimization, demonstrated through a case study on suspension brackets for heavy-duty vehicles. This case study is based on random load data collected from fatigue durability tests in proving grounds, and fatigue failures of the heavy-duty vehicle suspension brackets were observed and recorded during the tests. Multi-objective fatigue optimization was introduced by employing multiaxial time-domain fatigue analysis under random loads combined with the non-dominated sorting genetic algorithm II with archives.

It’s significant to analyze the Experimental performance of active control system for road noise. In this paper, a 2-channel active control system of vehicle road noise based on FXLMS algorithm is established. The complexity of Filtered-x Least Mean Square algorithm (FXLMS) is analyzed. The bench test and road test are carried out to test and analyze the performance of the control system. Firstly, the general mathematic model of the multi-channel active control system based on FXLMS algorithm is established. The computational complexity of the algorithm is analyzed. Secondly, a hardware-in-the-loop (HIL) test bench based on multi-channel FXLMS algorithm and a measurement system based on DASP are set up, to measure the noise reduction performance of active noise control system under various working conditions. Finally, the bench test and the road test are carried out and the results are analyzed.

The vehicle permanent magnet synchronous motor has the advantages of high power density, compact structure and small size, which makes it generate heat obviously in the process of energy conversion, which seriously affects the service life of the motor and the performance of permanent magnet. Predicting magnet temperature is a challenging task, in lab and various specialized applications, infrared sensors or thermocouples are used to measure the temperature, but it cost a lot. In order to predict the temperature field of the motor, the hysteresis characteristic test of the core material of the motor is carried out in this paper. The hysteresis characteristic and loss of electrical steel under different temperature, magnetic field intensity and magnetic field frequency are tested. It is found that the loss of electrical steel increases with the increase of magnetic induction intensity and magnetic field frequency.

The parameter setting has a great influence on the noise reduction performance of the road noise active control (RNC) system. This paper analyzes and optimizes the parameters of the RNC system. Firstly, the model of the RNC system is established based on the FxLMS algorithm. Based on this model, taking the maximum noise reduction as the evaluation index, the sensitivity analysis of convergence coefficient, filter order, and reference signal gain was carried out using the Sobol method with the data measured by a real vehicle on asphalt pavement at 40km/h. The results show that there is no significant interaction between the three parameters. Then, using the idea of orthogonal experiment, the simulation results of the control model are analyzed by taking the maximum noise reduction as the evaluation index. It is found that the convergence coefficient has the greatest effect on the maximum noise reduction, followed by the filter order, and the reference signal gain has the least effect.

It is considered that slow convergence speed and large calculation amount of commonly used adaptive algorithm in the active control system for vehicle interior noise yield noise reduction performance and hardware requirements problems. In this paper, a 4-channel active control of vehicle interior noise based on adaptive notch filter is established, and road test is carried out to test and analyze the performance of the control system. Firstly, the general mathematic model of the multi-channel active control system based on adaptive notch filter is established. The computational complexity of the algorithm is analyzed and compared with that of the FXLMS algorithm. Secondly, a hardware-in-the-loop test bench based on multi-channel adaptive notch filter is set up, to measure the noise reduction performance of ANC system under various working conditions.

The performance of the rear axle plays an important role in the performance of vehicle, and its fatigue durability is an integral part in the vehicle development. Taking a SUV model as the research subject, a new methodology of multi-channel spindle coupled road simulator and fatigue simulation analysis for rear axle assembly was introduced in the paper, aiming to address the fatigue design and its verification for the rear axle in the development phase. Firstly, road loads in the proving ground was collected by arranging proper sensors. Secondly, physical iteration was performed on the multichannel spindle coupled road simulator by taking six component forces at the wheel hub as the target signals. Then, after the time waveform replication of the loads the durability test was conducted. Finally, the validated simulation model was successfully implemented to improve the fatigue life of the axle.

The cab is an essential part of a light truck, and its fatigue durability performance plays an important role in the design and development stage. Accelerated fatigue bench test has been widely applied to product development of carmakers for its low cost and short development cycle. However, in reality, interference exists generally in torsional conditions for the light truck cab when tested on the 4-post vehicle road simulation system. To solve this problem and minimize the lateral force applied on the hydraulic cylinders, the direction and size combinations of displacement release about front and rear suspensions were discussed based on multi-body dynamics simulation and fixture design theory in this paper. Through comparative study, the optimum design and layout scheme of fixtures was determined to conduct the next test procedure. The weak positions of the light truck cab were firstly predicted by utilizing finite element method (FEM) and fatigue analysis theory.

The multi-body dynamics simulation and physical iteration were carried out based on the 4-channel road simulation bench, the solution of fatigue test bench which was suitable for cab with frame and suspension was designed. Large load and displacement above the suspension can be loaded on the test bench, and the same weak position of cab exposed on the road test can be assessed well on the fatigue test bench. The effectiveness of the bench test solution was verified though comparative study. And it has important reference for the same type of cab assembly with suspension in the fatigue bench test. According to the durability specifications of cab assembly, a multi-body dynamics model with a satisfactory accuracy was built. And the fixture check and virtual iteration analysis were used to verify the effectiveness of the solution. According to the road load signal analysis and multi-body dynamics analysis results, the test bench with linear guide and spherical joint was built.