刚柔混联欠驱动草莓采摘机械手动力耦合特性研究

我国大面积种植草莓多采用垄作栽培方式，加之草莓果实不定期成熟的生长特点，使得人工采摘草莓劳动强度和作业量非常大，由此开发一种代替人工作业的草莓采摘机构成为亟待解决的问题。针对草莓形状复杂、外表娇嫩的特点，本项目采用多指式机械手作为末端采摘装置，将刚柔混联欠驱动结构应用于手指单元的设计，并结合气动肌腱驱动实现草莓高效低损采摘。刚柔混联欠驱动手指单元实质是一类具有二阶非完整约束的动力系统，对其进行动力耦合特性分析是实现机械手可控性的首要问题。本项目融合柔顺机构学理论与分析力学原理，深入开展对手指柔顺构件构型综合与动力特性、刚柔混联欠驱动手指单元动力学建模及动力耦合特性等问题的研究；在此基础上，基于非线性控制理论，分析非完整约束的可积性，提出手指运动输出的可控性条件。本项目的开展可为刚柔混联欠驱动机器人的基础理论与应用研究提供参考，并为其在农业工程实践中的应用奠定基础，具有重要的理论意义和实用价值。

The most strawberry planting in our country are cultivated in way of hill culture. In the same time, the maturation of strawberry is aperiodic, which makes the intensity and quantity of labor large. Hence, it's an urgent mission to develop strawberry harvesting manipulator instead of manual labor. According to the feature of strawberry with complicated shape and delicate surface, the multi-finger manipulator is employed as the harvesting device, and the rigid-compliant structured underactuated framework is applied for the finge unit, that combine pneumatic muscle driver to implement flexible harvesting. The figer unit with rigid-compliant structured underactuated framework is essentially dynamic systems with second-order nonholonomic constraints, which make the study of dynamic coupling become the chief analysis for the controllability of manipulator. Based on the theory of compliant machanism and principles of analytical mechanics, this proposal is to investigate the structural synthesis of compliant machanism and dynamic characteristic, dynamic model building of rigid-compliant structured underactuated system, and the characteristic of dynamic coupling. On the basis of nonlinear control theory, the integrability of nonholonomic constraints is analysed, then controllability condition of motion is obtained. The above study can provide the referrence for basic theory and application of rigid-compliant structured underactuated robots, and give the foundation for the application in agricultural engineering.