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The guiding mechanism of vehicle suspension can keep the wheels moving along planned trajectory. The geometrical design of the reasonable suspension guide mechanism can reduce the vibration transmitted to the body, improve trafficability and handling stability. The vehicle suspension design method was applied to the wheel-legged vehicle, enhancing ride performance. The optimization of suspension hard points can be obtained by using single variable method, adjusting each hard point coordinate independently. It is also widely recommended by using intelligent algorithm to solve well-designed multi-objective parameter optimization function. In this study, the multi-objective parameter optimization function was solved by using the NSGA-II (Non-dominated Sorted Genetic Algorithm-II). Computer simulations with half-car model were used to support the analysis in this study. ADAMS multibody dynamics software was also used to verify the reliability of the results.

The wireless inter-vehicle communication provide a manner to achieve multi-vehicle cooperative driving, and the platoon of automotive vehicle can significantly improve traffic efficiency and ensure traffic safety. Previous researches mostly focus on the state of the proceeding vehicle, and transmit information from self to the succeeding vehicle. Nevertheless, this structure possesses high requirements for controller design and shows poor effect in system stability. In this paper, the state of vehicles is not only related to the information of neighbor vehicles, while V2V communication transmit information over a wide range of area. To begin with, the node dynamic model of vehicle is described by linear integrator with inertia delay and the space control strategy is proposed with different topological communication structures as BF, LBF, PBF, etc.

Nowadays, SC is recognized as a key element of hybrid energy storage system in modern energy supply chain for electric vehicles (EVs). Co9S8 as a promising electrode material attracts much attention for supercapacitor owing to its superior electrochemical capacity. However, its poor stability and electronic conductivity, which result in inferior cycling performance and rate capability, have seriously limited the practical application of Co9O8 in supercapacitors. In this article, Co9S8 nanoparticles were embedded in reduced graphene oxide (rGO) via a simple anneal approach as high efficient and stable electrodes for SCs. The Co9S8/rGO composites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The Co9S8 nanoparticles were inserted tightly between the rGO layers due to strong intermolecular forces, preventing the cluster in reduction process of rGO from graphene oxide (GO).

This research focuses on an integration of two optimal tracking controllers, the active suspension controller and the rear-wheel steering controller, with the objective of improving vehicle performances in terms of maneuverability and safety by enhancing road holding capability and lateral stability. The active suspension controller adjusts the vehicle roll angle and utilizes the vertical force at each active suspension to boost road holding capability. On the other hand, the rear-wheel steering controller adjusts rear steering angles to use lateral force at each ground-tire contact point and amplify the vehicle’s ability to follow the desired yaw rate and sideslip angle during cornering maneuvers. Though the active attitude motion and mass shifting of car body may seem to hold relationship with lateral stability, its ability to evenly distribute vertical tire forces benefits the rear-wheel steering controller by enhancing the road holding capability.

As a critical part of auto-body, the design of tailgate not only affects the beauty, usability and safety of automobile, but also involves more and more issues about environmental protection and energy saving. Hence, it is of vital importance to investigate lightweight of tailgate. This paper mainly focuses on lightweight design of CFRP tailgate based on conventional SUV metal tailgate, which can be realized under the condition of meeting requirements of stiffness, modal and manufacturing with the adoption of multi-step optimization method. To start with, finite element (FE) model of metal tailgate is established. Meanwhile, the stiffness and modal analyses, including bending stiffness, torsional stiffness, lateral stiffness, vertical stiffness and free modal are set up. Then, the structural performances of metal tailgate are analyzed, and the topology optimization of CFRP tailgate is performed.

Aiming at the trajectory planning of autonomous vehicles in lane changing under muti-lane traffic scenarios, a multi-lane lane change decision and trajectory planning algorithm based on Logic Regression Algorithm and Gaussian Probability Model is proposed. Firstly, the target state (time and velocity) of vehicle during lane change is sampled and lateral trajectory (5th polynomial) and longitudinal trajectory (4th polynomial) are planned based on the target state; Secondly, cost evaluation function of trajectory is established and optimal trajectory is selected based on three aspects of safety, comfort and lane changing time.

A vehicle-mounted anti-vibration system is designed to semi-actively reduce accelerations acting on vibration isolation platform under different road conditions. To provide the basis for optimal anti-vibration design, the kinematics and dynamics of the platform are analyzed to investigate the relationship between leg length, strength, the platform position and vibration properties. As the platform is fixed on vehicle, a combined vehicle-platform model is necessary for verifying the performance and applying some suitable control algorithms. Also, typical digital testing roads will be built using road load spectrum. To optimize the platform parameters, especially stiffness and damping, an active control system is designed at first. An anti-vibration system including a semi-active inerter is designed to match the control forces which are calculated from the above active system.

To resolve the problems of path curvature mutation and automatic parking path planning in complex scenes, a novel parking path planning method based on the combination of Reeds-Shepp curve and A-Star algorithm is proposed in this paper. To start with, the points from the planned path are selected based on Reeds-Shepp curve, whereby the planned path is segmented and optimized according to the combination of limited information collected by environmental perception system and A-Star algorithm, then the planned path of automatic parking is executed successfully in complex barriers scenarios. Subsequently, the effectiveness of the segmented path is verified with the adoption of MATLAB and real-vehicle test. It can be seen from the results that the path planned based on the combination of Reeds-Shepp curve and A-Star algorithm is proven to provide a smooth path, superior execution, and high security.

The concept of “bionic design” has driven the developments of automotive design. In this paper, a novel beak-shaped automotive tail fin with honeycomb cellular structure is proposed based on the idea of “bionic design”. Beak-shaped appearance is utilized to meet the requirement of aerodynamics performance, inner honeycomb cellular structure is filled to achieve more lightweight space. This paper starts from the establishment of three dimensional (3D) model based on the real characteristics of sparrow’s beak. On this basis, aerodynamic performances of novel beak-shaped tail fin and conventional shark tail fin are analyzed by experiment. Finally, the stiffness and modal analyses of solid beak-shaped tail fin and honeycomb beak-shaped tail fin are carried out respectively. The results indicate that the deformation of solid beak-shaped tail fin and honeycomb beak-shaped tail fin satisfy the basic requirements.

With the continuous improvement of positioning technology and industry demand, the shortcomings of each sensor are constantly amplified. Only relying on a single sensor, the demand of high-precision positioning and mapping for intelligent vehicles is difficult to be satisfied. The accuracy of system positioning and mapping is reduced due to the loss of feature points in pure visual SLAM as the environmental characteristics are not obvious or the texture is not abundant. IMU is a sensor with low cost and high update frequency, which can correct the running trajectory in real time and reduce the error of environmental factors on visual sensor data. Therefore, a method based on ORB_SLAM2 algorithm and VINS-Fusion algorithm, the stereo camera information and inertial measurement unit information are extracted and fused in robot operating system is proposed.

As one of the key technologies for EVs and HEVs, the design of their motors has been researched extensively, and some novel rotors of permanent magnet motor were proposed in order to improve torque capability, including average torque and torque ripple. Rotor structure selection of drive motor for various electric vehicles has been one of the key issues in matching of electric vehicle power system. Three motors are analyzed for providing visible insights to the contribution of different rotor structures to the torque characteristics, efficiency and extended speed range. First, an iterative comparative analysis of torque-speed characteristics with different flux linkage, d-axis inductance and rotor saliency ratio is performed for demonstrating the design principle. Then, the three motors are optimized by a genetic algorithm (GA) for further improving the torque characteristics.

The conventional hood with single material and stiffener structural form conceals some limitations on pedestrian protection and lightweight, not satisfying the requirements of structural strength, pedestrian protection and lightweight contradictory with each other at the same time. In this paper, a novel type hood is proposed to develop sandwich structure using architected cellular material with negative Poisson's ratio (NPR) configuration based on the decoupling thought of structural strength and energy absorption. Core-layer aluminum alloy material with NPR is used to meet the requirement of impact energy absorption, inner and outer skin using carbon fiber is selected to achieve high structural stiffness needed. This paper starts from the relations between geometric parameters of core-layer architected cellular material and mechanical properties, on this basis, the optimal geometric parameters can be expected using the multiobjective optimization method.

To resolve the issue of poor generality of current parking methods based on idle space, a panoramic parking path planning method based on DMPR-PS and Hybrid A-Star is proposed. In this paper, a pure vision approach is adopted, and a fisheye camera is selected as an image acquisition device to build panoramic parking assistance system. Subsequently, the parking slot directional marking points are obtained through DMPR-PS model, and the valid entrance line can be also acquired to recognize parking slot. The accuracy of parking slots recognition can reach 96.86%.Eventually, the planned path can be achieved based on the Hybrid A-Star algorithm where vehicle kinematics and obstacle avoidance constraints are considered. The effectiveness of the planned path can be verified with the adoption of MATLAB and real-vehicle test.

Gear transmission is widely used in mechanical transmission system and acts an important role in automotive industry. Manufacturing errors, assembly looseness, gear wear issues may result in gear backlash, noise and fatigue damage seriously affecting efficiency and service life of gear transmission. For gear transmission assembled, it is important to monitor the conditions of gear meshing and prevent the occurrence of dangerous situations. How to define the issues of gear tooth wear, misaligned bearing, gear eccentricity, backlash, and how to find faulty planetary gear sets and specific issues existing in gear transmission are meaningful and significant to ensure the quality of product. This paper starts from the analysis on gearing mechanism. Based on the behaviors represented by the issues, gear tooth wear, misaligned bearing, gear eccentricity and backlash are demonstrated and explained in detail.