CAJ | 학술논문

为了提高车轮牵引性能，改善车辆在松散沙土介质环境的通过能力，该文以善于沙地奔跑的鸵鸟足部关键部位—足趾甲为仿生原型，通过仿生优化轮刺结构，设计出具有高牵引性能的仿生轮刺式沙地刚性轮，并以一种模拟月壤作为试验松散沙土介质材料，采用离散元软件PFC2D?的内置语言FISH和相关命令，建立了适用于非规则结构刚性轮的轮壤相互作用动态模拟系统，并获得试验验证。通过仿生轮刺式刚性轮与模拟月壤相互作用离散元模拟，并与矩形轮刺式刚性轮模拟结果对照，从轮下模拟月壤颗粒细观运动、接触力场、速度场以及车轮挂钩牵引力角度，验证了仿生轮刺式刚性轮具有优越的牵引性能，在车轮滑转率50%的稳定运行状态下，仿生轮刺式刚性轮的牵引性能可提高5.2%左右。该研究为提高刚性轮在松散沙土介质环境中的牵引性能提供了全新设计和研究手段。
위료제고차륜견인성능，개선차량재송산사토개질배경적통과능력，해문이선우사지분포적타조족부관건부위—족지갑위방생원형，통과방생우화륜자결구，설계출구유고견인성능적방생륜자식사지강성륜，병이일충모의월양작위시험송산사토개질재료，채용리산원연건PFC2D?적내치어언FISH화상관명령，건립료괄용우비규칙결구강성륜적륜양상호작용동태모의계통，병획득시험험증。통과방생륜자식강성륜여모의월양상호작용리산원모의，병여구형륜자식강성륜모의결과대조，종륜하모의월양과립세관운동、접촉력장、속도장이급차륜괘구견인력각도，험증료방생륜자식강성륜구유우월적견인성능，재차륜활전솔50%적은정운행상태하，방생륜자식강성륜적견인성능가제고5.2%좌우。해연구위제고강성륜재송산사토개질배경중적견인성능제공료전신설계화연구수단。
It is very important to enhance the wheel traction performance for improving the traveling ability of the vehicle in the loose sand circumstance. The toenail, which is the key part of ostrich foot possessing the excellent running ability on sand, was regarded as the bionic prototype. Through bionic optimization of the wheel lug structure, the rigid wheel with bionic wheel lugs moving on sand with higher traction performance was designed. A kind of lunar soil simulants was selected as the experimental loose sand material. Using the built-in language FISH and the relevant command of Discrete Element Method (DEM) software PFC2D?, the dynamic simulation system, which was suitable for simulating the interactions between the rigid wheel with irregular structure and the loose sand material, was established. The simulation system was validated by the combination between laboratory test and DEM simulation. The interactions between the rigid wheel with bionic wheel lugs and the lunar soil simulants were simulated. The thrusts of lunar soil simulants were composed of four parts. The first part is the horizontal component forces of the tangential contact forces of the lunar soil simulant particles on the wheel outer boundary rim. The second part is the horizontal component forces of the normal contact forces of the lunar soil simulant particles on the wheel outer boundary rim after the bottom dead center. The third part is the normal contact forces of the lunar soil simulant particles on the lateral wall of the wheel active edge. The fourth part is the microscopic acting forces just like the horizontal positive component forces of the tangential contact forces. The moving wheel is subjected to the strong normal contact forces, caused by the compaction of the loads on the wheel and the cutting between the active side of the wheel rim and the lunar soil simulants. Because of the influences of the contact constitutive model characteristic of the lunar soil simulant particles, the small tangential contact forces of the lunar soil simulant particles are small. At the same time, the simulated results of the rigid wheel with bionic wheel lugs were compared with those of the rigid wheel with rectangular wheel lugs under the same simulation conditions. The simulated results showed that the bionic wheel lug presents three advantages. Firstly, the bionic wheel lug could solidify the loose lunar simulants under the moving wheel through driving the lunar simulant particles toward the bottom left part, which provided the larger adhesive forces for locomotion. In contrast, the rigid wheel with rectangle wheel lugs tended to increase the local voids by driving the lunar soil simulants toward different directions. Secondly, while entering into the lunar soil simulants, the bionic lug reduced the disturbance on the surface layer particles of the lunar soil simulants by the three typical smooth curves of the bionic lug, which caused the small angles between the bionic lug and the lunar soil simulant surface. Due to the sharp angle of the rectangular lug, the rectangle lug obviously disturbed the lunar soil simulant surface and made the lunar soil particles tend to move upward. Thirdly, comparing the rigid wheel with bionic wheel lugs to the rigid wheel with rectangle wheel lugs, the drawbar pull of the former was larger than the latter by 5.2% when the wheel slip coefficient was 50%. More lugs contacted with the lunar soil simulants in the rigid wheel with bionic wheel lugs and more contact force lines under this rigid wheel could account for the above quantitative results. This research provided a new design way to improving the tractive performance of the rigid wheels traveling in the loose sand condition.