In order to detect the driver’s fatigue driving situation in time, this paper proposed a yawn detection method based on Dlib and variant Transformer. First, the yawn feature matrix of the driver’s eyes and mouth was constructed based on the face key point model of Dlib. Then a variant Transformer model was proposed in the field of video detection, to extract the yawn feature matrix and classify the results. Finally, it was verified based on the YawDD dataset. The results show that the yawn detection accuracy of the proposed algorithm is 96.8%, which is higher than the existing algorithms, and is suitable for the detection of yawning behavior when the driver is fatigued.

For the problems of adaptive cruise control technology, including insufficient environmental adaptability of control algorithm for Deep Reinforcement Learning (DRL), poor model mitigation and generalization ability, this paper proposed the Soft Actor-Critic (SAC) control algorithm based on the principle of maximum entropy and stochastic off-line policy. SAC network was built to fit action value function and action policy function, and auto-adjusting temperature coefficient was used to improve the environmental exploration ability of intelligent agent. For the problem of sparse reward, the reward function was designed by using the idea of reward shaping. In addition, a new experience replay mechanism was proposed to improve the utilization rate of samples. The proposed control algorithm was simulated and tested in different scenes, and compared with Deep Deterministic Policy Gradient (DDPG). The results show that the algorithm has better model generalization ability and migration effect on real vehicles.

In order to improve the energy utilization rate of composite power pure electric logistics vehicle, this paper optimized the existing composite power energy management strategy combined with the road slope. Firstly, a fuzzy controller which can automatically adjust the output power of supercapacitor based on different road slope coefficients was designed. Then Particle Swarm Optimization(PSO) algorithm was used to optimize the fuzzy controller. Finally, MATLAB/Simulink was used in CYC_UDDS to set different slopes for simulation verification under urban road conditions. The simulation results show that the proposed control strategy can reduce the energy consumption by 3.47%, 28.91% and 3.94% respectively on the fixed uphill, fixed downhill and the actual urban road slope, so it can give better play to the advantages of supercapacitor.

To study the influence of different service cycles of BioRID II dummy on test evaluation results in the whiplash tests, 4 whiplash tests are carried out by taking 2 dummies with different service cycle seating the H-point x at the baseline position +5 mm and -5 mm respectively, meanwhile, the dummy’s neck structure and calibration descriptions are discussed. The results show that the difference in service cycle between BioRID II dummy has significant influence on the Neck Injuries Criteria (NIC) and the lower neck axial force, and the gap in the whiplash test evaluation may reach more than 0.5. The rationality of the current way of adjusting the neck My and the method and dimension of dummy calibration remain to be discussed.

In order to improve the safety of a commercial vehicle cab complying with the requirements of GB 26512—2011 real vehicle test and make it meet the requirements of GB 26512—2021, the Box-Behnken test design and Sequential Quadratic Planning (SQP) algorithm improvement were carried out for problems occurring in the cab simulation such as excessive peak force of longitudinal beam in frontal impact test, insufficient energy absorption in A-pillar impact test and serious crushing in side 20° impact test; and cab was optimized by setting bending beam and filling Expanded Polypropylene (EPP) foam material. The results show that after optimization, the longitudinal beam peak torque is reduced from 92.3 kN to 72.4 kN, the structural energy absorption is improved by 36.9%, the survival space is sufficient to meet the requirements of the new standards, and the cab safety is significantly improved.

In order to improve the safety of rear occupants with different sizes, this paper analyzed the damage of rear occupants in 100% frontal collision condition at 50 km/h by simulation. Firstly, a rear occupant restraint system model was established and verified. Then THUMS_AM50, THUNS_AF05 and CHARM-70 models were used to simulate different rear passenger sizes, Constant Loading Limit (Con-LL) curve, Progressive Loading Limit (Pro-LL) curve and Descending Loading Limit (Dig-LL) curve were respectively applied to explore the adaptability of seat belt loading curve to passengers of different sizes. The results show that the risk of neck ligament injury is great under this condition. The Dig-LL curve showed significant protection for the CHARM-70 but poor protection for the THUMS_AM50 during a frontal collision. Con-LL curve is not suitable for the protection of THUMS_AM50 and CHARM-70 under this condition. Pro-LL curves showed good protection for THUMS_AM50 and THUNS_AF05. In the future, the seat belt restraint system should be adapted to different loading curves according to the occupant type and collision condition to better protect the occupant.

To satisfy multiple objective performance requirements of B-pillar, a novel B-pillar with concave triangle Negative Poisson’s Ratio (NPR) cellular structure was designed. Firstly, the relative density equation of novel cellular structure can be derived by employing unit cell method. Then, quasi-static compression test was carried out on 3D printed cellular structure sample to verify the accuracy of finite element model. In addition, Genetic Algorithm (GA) was utilized to obtain the optimal structural parameters with the goals of maximum Specific Energy Absorption (SEA), minimum Peak Collision Force (PCF) and minimum relative density. Based on this, the thickness of B-pillar was optimized with the goal of minimum mass. Through analysis on 3 working conditions, it can be concluded that compared with the non-sandwich carbon fiber B-pillar, the backward bending displacement of the novel B-pillar decreases by 5.28%; compared with non-sandwich carbon fiber B-pillar and carbon fiber B-pillar, the lateral bending displacement of novel B-pillar decreases by 42.28% and 48.05% respectively, the maximum contact force of three-point bending increases by 80.08% and 12.63%, and the three-point bending displacement decreases by 0.02% and 2.14% respectively.

In order to improve the impact safety of integrated design of anti-collision beam, the multi-objective optimization model of anti-collision beam with crashworthiness and lightweight was transformed into game model and a mapping relationship was formed. The Specific Energy Absorption (SEA) and mass were taken as game parties, game distance and game moment were applied to establish the strategic attribution, and the model simulation was transformed into numerical optimization by combining the game utility function. The optimal solution was obtained through the Nash equilibrium analysis of the game utility function. The results show that the mass of the integrated anti-collision beam by the game design is reduced by 26.47% and SEA is increased by 22.18% compared with the initial design, and compared with the traditional optimization algorithm, the game design has better stability and optimization effect.

In order to study the feasibility of active-passive integration test based on acceleration sled, simulation and sled test were carried out on the 50th THOR dummy under 8.0 m/s² braking, and acceleration and deceleration simulation were carried out under frontal high-speed collision condition after AEB system braking. The results show that the occupant out-of-position fluctuates under AEB system braking, the maximum displacement occurs before the 300th ms, and the fluctuation range is small after the 400th ms. Under the simulation of acceleration sled, after the 400th ms, the protective effect of airbag on head and the stiffness performance of dummy chest are closer to the deceleration test. It therefore can be concluded that the active-passive integration test can be carried out on the acceleration sled by reducing the deceleration time of AEB under the circumstance of the reduced simulation time of AEB should not be less than 300 ms.

In order to improve the occupant protection performance of a vehicle in the frontal 25% offset crash test, the research on the test methods and optimization schemes of the evaluation items of the injury level of the dummy, the restraint system and the motion level of the dummy was carried out. First, an accurate model was established by simulation and benchmarking test. Then, side air curtain was added, the seat belt and ignition time and parameters of airbag were optimized, and the structure of steering column bracket and instrument panel bracket were also optimized. Finally, it was verified by CAE. The results show that the grades of the thighs and hips, legs and feet of the dummy have been improved from Marginal (M) and Poor (P) to Good (G) and Acceptable (A), and the evaluation items of the restraint system and the motion grade of the dummy have been improved from Poor (P) to Good (G). The overall evaluation of small offset crash was improved from Poor (P) to Good (G). The occupant Weighted Injury Criteria (WIC) decreased by 22.97%.