截角六面体可变形滚动机构

Truncated Hexahedron Deformable Rolling Mechanism

提出一种具有截角六面体几何形态的新型可变形滚动机构。该截角六面体可变形滚动机构是一个由16个杆和20个转动副组成的空间闭链连杆机构,采用了以面作为结构组成单元构造多面体机器人的一种新设计方法,具有可变外形与滚动行进能力,并通过对奇异位形的控制实现转向功能。应用螺旋理论计算构型的自由度。运用Solidworks建立的三维模型与ADAMS建立的动力学仿真模型,分析其具有的两种变形方式,即固定式变形与移动式变形方式,进而得到最大变形压缩比,并验证了变形与转向的可行性。结合运动学分析与稳定性分析,讨论该机构实现翻倒的条件并判断出临界值。制作出一台原理样机,对其进行变形方式与滚动功能的可行性验证,并实现预期的结果。此外,该类多面体移动机构具有较高的结构刚度,易于提高机器人的承载能力。

A novel deformable rolling mechanism with the geometric configuration of the truncated hexahedron is proposed. The rolling mechanism included sixteen links and twenty revolute joints is a spatial closed-chain linkage. A new design method chosen the regular triangle linkage as the basic construction unit is adopted to design the roiling mechanism. The rolling mechanism has the deformable and rolling capabilities, and its turning motion is controlled by using its singularity position. The screw theory is used to calculate the degree-of-freedom of the configuration. By applying the 3D model and dynamic simulation model built by Solidworks and ADAMS respectively, two deformation manners, stationary deformation and movement deformation, are analyzed. The maximum deformable compression ratio is obtained and the feasibility of its deformation and turning motion is proved. The tumbling condition is discussed and critical value is calculated by the kinematics and stability analysis. A prototype is fabricated to testify the two deformation manners and rolling capability, and achieve the expect results. Furthermore, the polyhedron rolling mechanism has a high structural stiffness, easy to increase the carrying capacity of the robot.