Autonomous commercial semi-trailers can greatly improve trunk logistics efficiency. However，since the semi-trailer vehicle is a typical underdrive system，it is difficult to simultaneously achieve lateral trajectory tracking accuracy of both tractor and trailer under large curvature motion conditions. With the increase of vehicle speed and load，the transfer of the trailer centroid and load intensifies，causing a strong uncertain impact on the hinge point between the tractor and trailer and the deviation of the driving trajectory between the trailer and the tractor to further increase，which increases the trajectory tracking difficulty and affects its driving safety. To enhance the lateral safety of semi-trailer commercial vehicle tractor and trailer，a robust path tracking strategy based on a type-2 fuzzy control algorithm is proposed in this paper. Firstly，a seven-degree-of-freedom dynamic model of the semi-trailer vehicle is constructed in MATLAB/Simulink to accurately simulate the transverse and longitudinal motion dynamics of both tractor and trailer. Secondly，considering the coverage property of the input membership function to system uncertainty in type-2 fuzzy logic control theory，a type-2 fuzzy controller is designed to adjust the lateral tracking accuracy of both tractor and trailer simultaneously. To improve the precision of lateral trajectory tracking control under uncertain factors and reduce the difficulty of controller design，a particle swarm optimization algorithm is utilized to optimize the input membership function parameters of the type-2 fuzzy controller. Finally，vehicle trajectory tracking simulation is conducted under various speed and load conditions using a joint simulation platform of MATLAB/Simulink and TruckSim to validate the control strategy proposed in this paper，and the tracking accuracy is compared with those using traditional type-1 fuzzy control and preview control. The results show that the proposed type-2 fuzzy controller can significantly enhance the lateral trajectory tracking accuracy of the tractor and trailer under the condition that track curvature changes with double shifting lines.

Focusing on the demand of intelligent driving under non-visual conditions，the millimeter-wave radar with the characteristics that can work all day and is less affected by light and weather is used to build a shape and position feature recognition model of crossable obstacles on the road in this paper. Taking the road speed bump as an example，the road obstacle feature perception system based on millimeter wave radar is constructed. The radar antenna plane faces the ground and has a certain angle with the ground to collect road information. The FFT-CZT two-stage processing structure is used to refine the spectrum of radar intermediate frequency data and to obtain the range value with high accuracy. Then，by analyzing the radar point cloud，the shortest target distance measured in each frame is fused to obtain the two-dimensional imaging of the road deceleration zone. Finally，through the analysis of visual data，the geometric model of road deceleration zone is established，and the calculation method of characteristic parameters of deceleration zone is put forward. A real vehicle-testing platform is established to collect data of different angles between millimeter wave radar and the ground from 0 to 90. The average absolute error of the estimated speed bump height at the included angle of 45 is within 4 mm，and the average absolute error of the estimated width is about 21 mm，which verifies the effectiveness of the method proposed in this paper.

In addition to the design and optimization of the catalyst layer （CL），the interface between CL and the microporous layer （MPL） also needs to be considered for the research of membrane electrode assembly （MEA）. In this paper，three different CL/MPL interface structures are fabricated to verify their effect on PEMFC performance and durability under simulated vehicle operating conditions. The performance test results show that the performance of the MEA sample obtained by introducing Nafion ionomers into the CL/MPL interface （MEA-Nafion） decreases slightly compared with the pristine sample （MEA-0） at high current density，whereas the performance of the MEA sample obtained by introducing Nafion ionomers into the CL/MPL interface followed by hot pressing （MEA-Nafion-HP） is basically the same as that of MEA-0. Specially，the durability test results under simulated vehicle conditions show that the voltage decay rates of MEA-0，MEA-Nafion，and MEA-Nafion-HP samples are 42.3，29.9 and 15.2 μV/h，respectively. In conclusion，the MEA durability can be greatly improved without affecting performance by optimizing the CL/PEM interface structure design.

An effective control strategy for fuel cell hydrogen systems can improve system dynamic performance and extend service life. In this paper，an adaptive sliding mode decoupling control strategy based on gradient optimization is proposed for circulating pump fuel cell hydrogen systems. Firstly，a fuel cell hydrogen system model is built based on Simulink. Based on this model，a decoupled sliding mode controller is designed to compensate for inaccurate model accuracy while achieving decoupling of flow and pressure. The stability of the feedback control rate is demonstrated through Lyapunov principle. However，sliding mode control has the problem of conflicting dynamic response performance and chattering. In response to this，in this study a gradient descent based sliding mode control parameter adaptive optimization method is further designed，and the system stability under variable loads is improved through a feedforward controller. At the same time，the sliding mode optimization parameter MAP self-learning method iss adopted to solve the gradient optimization delay problem under transient conditions while ensuring the stability of the closed-loop system. The results show that the adaptive sliding mode decoupling controller combined with feedforward designed in this paper has small overshoot，short response time，and high robustness. The maximum pressure difference between the anode and cathode is about 0.01 bar，and the maximum flow supply error is 0.015 g/s，which is capable of quickly responding to changes in hydrogen pressure and flow rate during variable load operation within 0.02 seconds. Compared to that before feedforward correction，the pressure fluctuation during the start-up condition of the fuel cell stack has decreased by 0.122 bar. Under disturbance，the system stability remains good，and the maximum fluctuation of hydrogen pressure is 0.01 bar.

In order to investigate the electrical response of proton exchange membrane fuel cell （PEMFC） stack under impact load，and to reveal the mechanical-electrical coupling mechanism of PEMFC stack，the mechanical-electrical coupling modeling method of the PEMFC stack under impact load is studied. A systematic investigation is undertaken to investigate the effect of impact velocity and direction on the electrical response of the PEMFC stack，based on the established mechanical-electrical coupling model of the PEMFC stack. The results show that the proposed method for modeling the mechanical-electrical coupling of the PEMFC stack can accurately simulate the inherent mechanical-electrical coupling characteristics within the PEMFC stack. The ohmic loss of the single cell inside the PEMFC stack increases as the shock load increases. Meanwhile，the impact load results in the formation of additional electrical contact between the gas diffusion layer （GDL） and the ribs of the bipolar plate，which causes a reduction in the average value of the current density on the surface of the GDL and deterioration in the distribution uniformity. This study has certain guiding significance for the modeling of PEMFC mechanical-electrical coupling and the study of electrical response under impact load.

To achieve accurate prediction of electric vehicle remaining range，a method based on a three-layer weighted stacking model for predicting remaining range of electric vehicles is proposed in this paper. By combining the maximal information coefficient and Spearman correlation coefficient as criteria for variable evaluation，the minimum redundancy maximum relevance algorithm is employed to optimize and obtain the input feature set from the candidate features. A three-layer stacking model that incorporates the original training features is then constructed，and Bayesian optimization algorithm is used to determine the weights of the base models within the stacking model. Finally，the input feature set is used to train the three-layer weighted stacking model and realize electric vehicle remaining range prediction. The results show that the proposed three-layer weighted stacking model has high prediction accuracy and，compared to other models，with stronger generalization capabilities.

In order to conduct more comprehensive safety analysis of electric cars in side pole collision scenarios，in the paper a locally refining scheme is used to build the finite element model of battery pack，which is applied to simulation at both the whole car and the battery pack levels. Based on accident statistics，the side pole collision responses of the car are examined by changing the impact positions，angles and collision speed，including the conditions defined in the national standards. Considering the high cost of the whole car simulation，a parameterized model of battery pack level is established by adjusting collision speed and mass compensation for large-scale side pole collision simulation. A fast prediction model based on the energy method is proposed for battery pack level collision safety，which can predict the deformation and mechanical failure risk in real time under different side pole impact conditions. The model is validated with an average prediction error of 3.22%.

In order to study the relationship between driver style，collision avoidance parameters and collision avoidance rate in vehicle-vehicle collision accidents to improve driving safety，in the paper five typical scenarios are analyzed by clustering videos of 610 real accidents in the Vehicle-Vehicle Traffic Accident database （VV-TRAVi，Vehicle-Vehicle Traffic Accident database with Video）. Among them，intersections account for the largest proportion，mainly divided into two typical collision scenarios with and without visual obstacles，based on the six-degree-of-freedom driving simulator to dynamically build the above two typical collision scenarios at intersections. Through questionnaire survey，principal component analysis and K-mean clustering，the driving styles are classified into aggressive，normal and cautious，with 60 volunteers of the three driving styles recruited to collect experimental data under the two typical collision scenarios constructed. The collision avoidance parameters under the three styles are extracted from the 92 sets of valid data samples： TTC （time-to-collision），BRT （braking reaction time），speed and longitudinal deceleration，and the effect of the three driving styles on the above collision avoidance parameters are analyzed using one-way ANOVA and independent samples t-test. The results show that the TTC，BRT，speed and longitudinal deceleration of the three driving styles show significant differences in the two typical collision scenarios with and without visual obstacles. Among them，the mean values （s） of the TTC for the aggressive，normal and cautious styles are 0.54 and 1.21，0.59 and 1.33，and 1.01 and 2.58，and those of the BRT are 1.12 and 0.9，1.32 and 1.3，and 1.6 and 1.56，respectively，both of which show a sequential increasing trend； the mean speed （km/h） values are 37.53 and 45.03，30.37 and 34.93，and 27.62 and 30.37，respectively，and the mean longitudinal deceleration （m/s²） values are 9.38 and 9.13，6.2 and 5.6，and 3.92 and 3.66，respectively. Both of them show a decreasing trend. The crash avoidance rates of the three driving styles are "Cautious > Normal > Aggressive". The results of the study provide a reference for the development of vehicle crash avoidance strategies that take driving styles into account.

High performance active suspension has significant advantages in improving driving experience，and robust control algorithm is an important guarantee for active suspension performance. To solve the problem that the typical robust control algorithms are difficult to achieve effective disturbance estimation and compensation，in this paper，a H₂/H_∞-H₂-IUDE algorithm is proposed to estimate and compensate the disturbance by using IUDE algorithm and introducing in H₂ state observer，which improves the robustness compared with H₂/H_∞ algorithm. Firstly，the model of half vehicle active suspension control systems is established，and the disturbance form is defined. Then，an IUDE algorithm for disturbance estimation and compensation decoupling is proposed，and a H₂ state observer is proposed to redesign H₂/H_∞ algorithm. Finally，simulation analysis is carried out for typical working conditions such as random road surface and speed bump road surface. The results show that，compared to the H₂/H_∞ algorithm，the proposed algorithm reduces the root mean square values of the vehicle body center vertical acceleration and pitch angle by 7.6% and 5.9%，respectively，under random road conditions，demonstrating a significant improvement in vehicle ride comfort. Meanwhile，the proposed H₂ observer can effectively estimate system states. The IUDE algorithm can accurately estimate disturbance，and can avoid the deterioration of suspension dynamic deflection caused by the non-decouple UDE method，which has outstanding characteristics of excellent disturbance estimation and flexible compensation.

To deeply investigate dynamic and static mechanical properties of non-pneumatic tires under the condition of unstructured road，double-arrow cellular structure （DACS） with negative Poisson's ratio （NPR） with excellent mechanical properties is embedded into non-pneumatic tires as a novel support structure and double-arrow non-pneumatic tire （DANT） is selected as research object herein. Firstly，finite element models （FEM） of DACS with various gradient densities are developed，and quasi-static compression tests are conducted on DACS samples to verify the accuracy of FEM. Then，FEMs of DANT are established to obtain effect of layer number of double-arrow support structure on static properties of DANT，and influence of structural parameters of support structure on modal and ground properties of DANT are investigated. Finally，dynamic mechanical properties of DANT on unstructured road surfaces are investigated，including steady-state rolling，obstacle traversing，ditch crossing，and soil contact. The results show that the rolling resistance of DANT increases from 11.51 to 241.66 N with increment of radial load from 1 000 to 5 000 N. Meanwhile，a partial detachment of tread and ground come up with the increase of water velocity，and the stress distribution of support structure and the magnitude of contact stresses can be affected by the height and width of the obstacles. The spread and plastic deformation of soil occurs from contact location as soil is subjected to forces of DANT.