Abstract: Under the action of the crawler of the tracked vehicle, the soil compaction produces a displacement.with transverse perturbation so the affected area under the interaction between the track and the soil is 3D. To analyze the trackterrain interaction more entirety and forecast the drawpull, the trackterrain interaction should be analyzed from the view of 3D. At first, MckyesAli 3D model was used to analyze the interaction of the baffle and the terrain, and the similarity of the baffleterrain interaction and trackterrain interaction was discussed. The 3D model was used to analyze the trackterrain interaction. The effectiveness of the 3D model was verified by using the experimental data and choosing the drawbar pull as evaluation criteria. And by comparing the 3D model with Bakker model, the predicted value from the 3D model is closer to the measured value. The study of 3D model provides the reference for the further study of the trackterrain mechanics and also provides a theoretical basis and foundation for the analysis of the interaction between the track and the terrain in the 3D space.

Key words: basic mechenics, track-terrain interaction, 3D model, drawbar pull, soft soil