Trajectory planning for multi-robot coordinated towing system based on stability

Given the unconstrained characteristics of the multi-robot coordinated towing system,the rope can only provide a unidirectional constraint force to the suspended object,which leads to the weak ability of the system to resist external disturbances and makes it difficult to control the trajectory of the suspended object.Based on the kinematics and statics of the multi-robot coordinated towing system with fixed base,the dynamic model of the system is established by using the Newton-Euler equations and the Udwadia-Kalaba equations.To plan the trajectories with high stability and strong control,trajectory planning is performed by combining the dynamics and stability of the towing system.Based on the dynamic stability of the motion trajectory of the suspended object,the stability of the suspended object is effectively improved through online real-time planning and offline manual adjustment.The effectiveness of the proposed method is verified by comparing the motion stability of the suspended object before and after planning.The results provide a foundation for the motion planning and coordinated control of the towing system.

浮动基多机悬吊系统动力耦合响应分析

为了研究浮动基多机悬吊系统在不规则波作用下的动力耦合关系,首先利用动量定理和动量矩定理建立了浮动基机器人动力学模型,其次利用达朗贝尔原理建立了悬吊系统的动力学模型,并提出了系统动力学的耦合关系分析步骤;最后结合实例,仿真分析了浮动基多机器人协调悬吊系统在不同波高、不同波长比和不同起吊速度下动力耦合响应过程。结果表明,该系统的理论研究进行了补充和完善,同时也为浮动基多机悬吊系统在实际的吊运过程中,判断安全的吊运环境提供技术支撑。

刚柔耦合串并联康复机械臂运动特性分析

针对目前大多数上肢康复机器人在结构上存在的不足,首先,设计了一种兼具绳索驱动和并联机构优点的4自由度刚柔耦合串并联康复机械臂。其次,在基于此康复机械臂绳索空间和关节空间映射关系的条件下,运用D⁃H坐标法建立了康复机械臂的运动学模型。最后,在Matlab环境下,仿真分析了各关节角与绳长、速度随时间变化的关系曲线。分析结果表明,该刚柔耦合串并联康复机械臂结构设计的合理性,也为分析康复机械臂的轨迹规划问题提供理论基础。

Trajectory compensation for multi-robot coordinated lifting system considering elastic catenary of the rope

The multi-robot coordinated lifting system is an unconstrained system with a rigid and flexible coupling.The deformation of the flexible rope causes errors in the movement trajectory of the lifting system.Based on the kinematic and dynamic analysis of the lifting system,the elastic catenary mod-el considering the elasticity and mass of the flexible rope is established,and the effect of the deform-ation of the flexible rope on the position and posture of the suspended object is analyzed.According to the deformation of flexible rope,a real-time trajectory compensation method is proposed based on the compensation principle of position and posture.Under the lifting task of the low-speed move-ment,this is compared with that of the system which neglects the deformation of the flexible rope.The trajectoy of the lifting system considering the deformation of flexible rope.The results show that the mass and elasticity of the flexible rope can not be neglected.Meanwhile,the proposed trajectory compensation method can improve the movement accuracy of the lifting system,which verifies the ef-fectiveness of this compensation method.The research results provide the basis for trajectory plan-ning and coordinated control of the lifting system。

浮动基多机协调吊运系统的动力学建模与仿真

针对目前海上使用的起重机在承载能力和作业空间上存在不足的问题,本文提出一种浮动基多机协调吊运系统来填补海上吊运的需求。根据吊运任务建立了系统的空间构型,并利用D-H坐标变换法建立了系统的运动学方程。根据刚体动力学和流体动力学理论建立了吊物系统和浮基的动力学模型。利用系统的运动学方程,分析了系统的正逆动力学问题,并且进行了时域仿真。结果表明:以负载运动和浮基运动分别为系统的初始激励,负载会对浮基运动造成很大的影响,同时浮基运动也会消耗负载的动能,两者均会影响到海上吊运作业的安全。因此,在动力学分析后,需要对负载的防摆控制和浮基的稳定性进行研究。

多机协调吊运系统在波浪作用下的动力响应

介绍了一种用于海上吊运的柔索式多机器人协调并联系统。由于浮动基座受到的合力大小和方向不断变化,极易使吊机倾覆。首先将系统分为浮式机器人和吊物系统两部分,利用流体力学理论和球摆模型分析了两者的动力学特性。然后根据系统流固耦合的特点,分析得到了在波浪作用下求解该系统响应的具体步骤。最后结合实例,在波浪工况下对不同数量的吊机的动力响应进行了对比仿真,获得了浮基的位移、吊物的摆动以及柔索张力等结果,所得结论为该系统的优化和控制打好基础。

浮动基多机协调吊运系统的仿真分析

目前,海上使用的起重机在灵活性和安全性上存在不足,文中提出一种漂浮式多机协调吊运系统来弥补海上吊运的需求。采用坐标变换法和流体力学理论分析了系统的运动学和动力学特性;根据系统的空间构型和吊运任务进行实体建模,并对吊运系统及周围水域划分网格和设置边界条件;采用Fluent软件在波浪作用下对基座的运动进行仿真,获得了起吊重物时浮基的位移和摆角等运动响应曲线,所得结论可为该系统的稳定性分析和评价提供参考。