| With the advance of agricultural mechanization layer by layer,regional agriculture represented by hills and mountains has a good prospect.However,due to the special terrain in this area,such as large vertical height difference,steep slope and many land fragments between fields,large agricultural machinery equipment and wheeled motion mechanisms that are widely used in plain areas cannot effectively complete the work and passage in this area.Therefore,there is a vast market for agricultural machinery equipment suitable for working in hilly and mountainous environments.The crawler movement mechanism has the characteristics of light and flexible.Compared with other movement mechanisms,the performance of the crawler movement mechanism is consistent with hills and mountains.Therefore,the development of a crawler agricultural mobile platform suitable for hilly and mountainous areas has a positive role and practical significance for promoting the process of agricultural mechanization in hilly and mountainous areas.By combining with the characteristics of hilly and mountainous landform and terrain,this paper designs a crawler mobile platform.Based on the dynamic model of the platform,the passing performance,attitude description and control results of the mobile platform are evaluated and analyzed through theoretical research,motion simulation and dynamic analysis.The main work is as follows:Firstly,the application scenarios and work requirements of the crawler mobile platform were summarized and analyzed,and the design objectives and design schemes of the mobile platform were established.On this basis,the design and selection of the mobile platform power system,transmission mode,frame structure and the key components of the internal gear train are carried out.The kinematic attitude of the designed platform is summarized and the principle analysis is carried out,and the strength analysis of the overall structure of the designed frame is carried out,which provides a model basis for subsequent research and test.Secondly,taking the traversability index of the mobile platform as the entry point,the principle part and mathematical model of the tracked platform are studied,which mainly includes the obstacle analysis of the tracked platform,the description of the pitch attitude change,the traversability analysis of the uphill and downhill,the slope stability analysis,the gully traversability analysis,and the overview of the steering attitude.The results show that: The limit slope,maximum gully and maximum obstacle crossing height of the tracked platform are 56°,1.3m and 0.52 m,respectively.The research on the principle level lays a theoretical foundation for the subsequent modeling and simulation of the dynamic model and even the attitude control.Then,Soild Works and RecurDyn were used to build the multi-body dynamics simulation model of the crawler mobile platform,and Matlab＿Simulink was used to establish the random road surface.The dynamics-road model was successfully completed,which provided the platform foundation for the dynamics simulation.Finally,based on the expected goal and principle analysis,the dynamic simulation analysis of the straight line traversability,slope traversability,obstacle traversability and gully traversability of the tracked mobile platform was carried out.The results show that the tracked mobile platform can complete the traversability simulation of the expected target obstacles such as 40° steep slope,0.4m obstacles and 0.8m gullies.The ultimate slope,maximum gully displacement and maximum obstacle crossing height of the tracked mobile platform are 50°,1.2m and 0.5m,respectively.The error ranges with the theoretical limit are 4%,7.7% and 12%,which proves that the mobile platform has good passability. |
PDF Full Text Request