基于滑块摇杆机构的柔性三指机器人手爪研究

多指机器人手爪普遍存在指端作用力弱的问题,柔性机器人手爪也出现末端作用力不足的现象，采用气压驱动的软体手爪虽驱动力增强，但不利于手爪控制的准确性，为此，设计了一种基于滑块摇杆机构的柔性三指机器人手爪。该手爪每根手指的指尖、指中节采用滑块摇杆机构实现，不仅增强了指端作用力，而且结构简单、易实现。为避免手指与目标物的刚性接触，手指尖、指根运动均通过弹簧来实现手爪的柔性;指尖驱动弹簧设计得较软，有利于初始接触的柔性;指根采用腱传动方式，指根腱采用较硬的弹簧来传递舵机扭力，可保证足够的作用力;手指表面均设计有较平的表面，有利于粘贴触觉传感器。通过理论分析与计算，证明指尖可获得较大的作用力，并分析了弹簧的选取方法。通过抓取实验证明本文设计的机器人手爪具有较好的适应性和抓取能力;与本课题组前期设计的钢丝绳耦合欠驱动式机器人手爪进行了抓取力对比测试，结果表明，手爪的抓取力有了很大提升，最大抓取质量达1.71kg;通过测试指端正压力与驱动舵机旋转角的关系以及抓取典型目标物的损伤情况，证明了设计的手爪具有一定柔性。有关性能实验证明了设计的手爪具有较好的实用性。

Flexible Robot Hand Based on Slider and Rocker Mechanism

A variety of the multi-finger robot hands have been developed up to now. However, most of them have weak force at the fingertip. Some of the flexible robot hands also have weak force at the fingertip. Although the soft hand with pneumatic actuation can have strong driving force, their control precision is low. A flexible robot hand based on slider and rocker mechanism was designed. It had three fingers. In each finger, the fingertip and the middle phalange were realized through a slider and rocker mechanism for which the force of the fingertip was strengthened. The tendon transmission was used for the proximal phalange, which guaranteed the driving force. The springs were used for the motion of the fingertip and proximal phalange to avoid the hard contact at the object. The spring that drove the fingertip was soft for good flexibility at initial contact. The spring that drove the proximal phalange was moderately hard to guarantee the sufficient force. The fingertip can achieve strong force through the mechanic analysis and computation. The analysis was performed on how to determine the springs. The experiments on grasping different common objects showed that the proposed robot hand had good adaptability and grasping ability. The experimental results on grasping force tests proved that the proposed robot hand can grasp much heavier objects compared with the former robot hand also designed by our research group. It can grasp an object with the maximum weight of 1.71kg. The tests on the relationship between the normal force of the fingertip and rotational angle of the servo motor of the proximal phalange and the destruction tests on grasping some typical objects were performed. The results showed that the proposed robot hand had good flexibility. These performances indicated the usefulness of the proposed robot hand.