## 6 Conclusions  
In this paper, to achieve anti-slip control for distributed electric drive vehicles on low-adhesion icy and snowy roads, an adhesion coefficient estimator based on improved singular value decomposition unscented Kalman filter and a slip ratio controller based on dynamic adaptive compensation sliding mode control was designed, and a simulation model was built for validation. The conclusions are as follows:  
* The proposed improved estimation algorithm and tire longitudinal force fusion estimation method can effectively estimate the adhesion coefficients on split roads and joint roads and can track well even when there are sudden changes in the road adhesion coefficients. Through adaptive improvements and fusion of the algorithm, the average estimation error of the road adhesion coefficients for the left and right wheels on  
Figure 8: Simulation results of acceleration on the joint road. (**a**) Wheel slip ratio without control. (**b**) Front and rear wheel slip ratios under CESMC control. (**c**) Front and rear wheel slip ratios under DASMC control. (**d**) Front and rear wheel torques under CESMC control. (**e**) Front and rear wheel torques under DASMC control. (**f**) Comparison of vehicle speeds under different controls.  
split roads was reduced by 63% and 84%, respectively. On joint roads, the average estimation error decreased by 69%, demonstrating the effectiveness of this estimator in estimating road adhesion coefficients and its quick response to sudden changes.
* The proposed DASMC slip ratio control algorithm can significantly reduce chattering compared to the CESMC control algorithm. The controller's response time is shortened by 66%, and the overshoot is reduced by more than 0.25. In terms of torque output and speed tracking, the improved control algorithm can quickly and smoothly output torque, with the speed curve closely matching the target curve. This demonstrates that the vehicle has excellent acceleration performance on low-adhesion road surfaces.
* At the transition of road adhesion coefficients, the improved DASMC control algorithm can adaptively adjust according to road conditions, keeping the switching time within 0.1 s and reducing the overshoot to nearly zero, ensuring smooth and stable control at the transition.  
However, the proposed method is limited to longitudinal vehicle dynamics without considering lateral stability and lacks verification under complex extreme conditions. In future research, coordinated control of longitudinal and lateral anti-slip and stability under complex conditions will be considered to improve the vehicle's dynamic safety and handling performance. Additionally, experiments will be conducted on real vehicles under city and snowy road conditions for validation.  
Conceptualization, J.F. and X.S.; methodology, X.S.; software, Z.X. and Z.W.; validation, J.F. and Z.X.; formal analysis, X.Z.; investigation, Z.X. and X.S.; resources, Z.X. and X.S.; data curation, X.Z.; writing--original draft preparation, J.F.; writing--review and editing, Z.X.; visualization, Z.W.; supervision, X.S.; project administration, J.F.; funding acquisition, X.S. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Natural Science Foundation of Jilin Province (YDZJ20201Z YTS513).  
Not applicable.  
Data Availability StatementData is contained within the article.  
The authors declare no conflicts of interest.