基于行波理论的桁架结构传感器优化布设方法研究

OPTIMAL SENSERS PLACEMENT METHOD FOR TRUSS STRUCTURE UPON TRAVELING WAVE THEORY

针对桁架结构传感器优化布设问题,根据行波在桁架结构中的传播特性,以损伤敏感程度最大化为目标,引用图论,并结合行波动力学,提出基于行波的传感器优化布设方法。将桁架的杆件、节点与图论的边、节点建立映射关系,对图论中的广度搜索法进行改进,以考虑行波在桁架结构中沿节点散射和反射的特点,获得行波在桁架结构中的传播路径。通过行波动力学分析,计算各类节点连接形式的行波传递系数,进而与传播路径相结合求得相同时间内所有节点对行波所致振动的敏感系数。基于敏感系数求取敏感总值矩阵,找出对各杆件最为敏感的激励点和传感器布置点。仿真模型和实验桁架结果表明,所提方法所得传感器布置位置对损伤最为敏感,为大型桁架结构传感器优化布设提供了新的方法支撑。

To deal with the problem of optimal sensor placement in truss structures,a sensor optimal placement method is proposed with the graph theory and traveling wave mechanics as the goal to maximize the damage sensitivity,according to the propagation characteristics of traveling waves in truss structures.Established was the mapping relationship between the truss members and nodes with the edges and nodes of graph theory,and extended was the breadth search method of graph theory to consider the scattering and reflection characteristics of traveling wave along the nodes in truss structures,thus obtained was the propagation path of wave traveling in the truss structure.Through the analysis of traveling wave dynamics,calculated are the transmission coefficients of traveling waves of various node connections,and then combined with the propagation path,acquired are the sensitivity coefficients of all nodes to the vibration caused by traveling waves in the same time.Calculated upon the sensitivity coefficient was the sensitivity total value matrix,and found out was the most sensitive excitation point and sensor placement point of each member.Simulation model and experimental truss results show that:the sensor placement position obtained by the method proposed is most sensitive to damage;provides a new way for the optimal placement of sensors in large truss structures.