多自由度柔顺机构在微动精密定位和精密操作等领域有广泛的应用,并且柔顺机构拓扑优化后所得机构都是锯齿状跳跃边界的几何图像,不能直接应用于工程实际,因而对多自由度柔顺机构拓扑优化、提取与试验研究就显得十分必要。基于此,以二维微执行器为例,进行多自由度柔顺机构几何非线性拓扑优化、拓扑图提取与试验研究。首先,给出了考虑耦合抑制输出的多输入多输出柔顺机构几何非线性拓扑优化数学模型及优化算法。其次,针对柔顺机构性能特点,给出了一种拓扑提取方法。提取过程包括灰度图像二值化、密度等值线方法边界近似和曲线重构三个部分。最后,以二维微执行器为基础,采用线切割加工工艺,研制了二维微执行器原型,并对其位移性能进行了试验测试,结果表明,该二维微执行器试验结果与理论分析结果基本吻合,达到了设计要求,同时也验证了所提方法的有效性。
Muluple degree-of-freedom(DOF) compliant mechanisms are widely used in the fields of micro-positioning and micro-manipulation,and the topology optimization will create final topologies in grey level image and sawtooth jump discontinuity boundaries that are not suitable for direct engineering practice,so it is highly necessary to study the topology optimization of multi-DOF compliant mechanism,topology extraction and experimental investigation.Taking the two-DOF micro-actuator as an example,the geometrically non-lineal topology optimization,extraction and experiment of multiple DOF compliant machanisms is studied.Firstly,the topology optimization model considering the suppression strategy of input and output coupling terms and optimization algorithm is developed.Secondly,according to the specific characteristics of compliant mechanisms,a topology extraction method is presented,which includes image preprocessing,boundary extraction using the density contour method,and geometric reconstruction.Finally,based on the topology mechanism and the restriction of fabrication technology,the prototype of the two-DOF micro-actuator is determined.The prototype is fabricated by means of linear cutting technology.The displacements of the two-DOF micro-actuator are measured by the control system.The experimental results show that properties of the two-DOF micro-actuator can satisfy the design demand and the effectness of this approach is verified.