Study on Method and Compensation Technology of off-axis Wedge Aspheric Parallel Grinding

针对精密光学系统中对高精度离轴楔形非球面透镜的加工要求,提出采用由倾角可调三轴摆动式数控夹具系统和精密磨床数控系统(COMPuTEr nuMErICAl COnTrOl,CnC)协调完成离轴楔形非球面透镜的高效加工方法。设计三轴摆动式数控夹具机构及控制系统相关程序,完成夹具制造及调整,在数控精密平面磨床上实现对离轴楔形非球面平行磨削加工。倾角可调夹具的设计简化原有的加工工序,提高加工效率。根据平行磨削加工原理对加工插补误差和工件形面误差进行模拟计算,结果表明:夹具旋转误差以及工件的形状尺寸会对加工精度产生较大影响。根据模拟结果和平行磨削方法原理,设计工件加工误差的在位补偿方法。通过平行磨削加工及补偿试验证明:在位补偿方法可以有效提高工件的加工精度。To satisfy the machining requirement of high-precision off-axis wedge aspheric lens in precision optical system,a grinding method of off-axis wedge aspheric with high efficiency using the coordination of the 3-axis computer numerical control(CNC) clamp and high-precision CNC grinding system is presented.The structure of 3-axis rotation CNC clamp and the control software are designed and achieved.The parallel grinding method of off-axis wedge aspheric lens is realized in the CNC plane grinding machine by using the proposed clamp.It simplifies the grinding process and improves machining efficiency.The interpolation error and machining profile error are simulated according to the principle of parallel grinding.The simulation results show that the rotation errors of clamp and the workpiece's sharp have an effect on the machining accuracy remarkably.Based on the simulation results and the principle of parallel grinding,the onsite compensation method is implemented.The machining and compensation experimental results show that the machining accuracy can be improved effectively through compensation method.国家高技术研究发展计划(863计划;2008AA042501);福建省科技重大专项/专题(2006HZ0002-4)资助项

Movement Modeling and Control of Precession Mechanism for Bonnet Tool Polishing Large Aixsymmetrical Aspheric Lenses

研究大口径轴对称非球面气囊抛光进动运动建模及控制。分析气囊抛光机构及大口径轴对称非球面抛光进动工艺特点,确定以气囊自转轴线与气囊交点为研究对象,以气囊球心为原点建立气囊进动基础坐标系,根据大口径轴对称非球面连续进动抛光中各抛光点气囊自转轴与局部法线夹角值(即进动角)不变的原理,在分析每个抛光点时建立与其对应的坐标系,得到抛光该点时气囊自转轴与气囊交点在该点对应坐标系中的值,而后进行坐标变换,将抛光任意点时气囊自转轴线与气囊交点的位置换算至气囊进动基础坐标系中;根据大口径轴对称非球面方程、加工控制模型及前述的坐标变换运算结果,利用矩阵变换得到大口径轴对称非球面抛光的进动运动模型;在上述的运动模型中加入最有效率控制算法后进行运动学仿真,得到大口径轴对称非球面抛光的进动运动曲线,并通过仿真气囊自转轴线跟随加工点法线变化的趋势及比较仿真进动角与实际进动角验证所建立运动模型及控制算法的正确性。Movement modeling and control for bonnet tool polishing large axisymmetrical aspheric lenses is present.The intersection point of the spin axis and the bonnet is selected to be object,after analyzing the structure of bonnet tool and process feature of large axisymmetrical aspheric lenses polishing;a base coordinate is set up with the centre of bonnet to be its origin point.As the included angle of the spin axis of bonnet tool and the local normal is fixed in continuous precession polishing,a corresponding coordinate is set up to get the position parameters of the intersection point of the spin axis and the bonnet when polishing a random point,the position parameters of the intersection point of the spin axis and the bonnet in base coordinate are got according to space coordinate conversion;Movement model is obtained by space matrix transformation,based on the surface equation of large axisymmetrix aspheric lenses,processing control model and the position parameters got in last step;Finally,most efficiency algorithm is added to the movement model,and precession motion curve is got by simulation.The correctness of movement model and control algorithm is confirmed through simulating the trend of spin axis of bonnet follows the local normal and comparing the simulated value of precession angle with the actual value of precession angle.国家自然科学基金(51075343);厦门市科技计划(3502Z20113007)资

Dynamic Removal Function Modeling of Bonnet Tool Polishing on Optics Elements

目前对于光学元件气囊抛光系统驻留时间的求解都是基于静态的去除函数,然而实际抛光过程中,抛光头不断地移动,故对于动态去除函数的研究显得尤为必要。通过有限元仿真分析的方法得到动静态接触区的轮廓和接触应力分布数据,发现对于平面工件,动静态接触区均为圆形,而且大小基本一致,且动态接触区应力分布与静态接触区应力分布相比,其峰值点沿抛光头移动的相反方向偏移。在此基础上,根据静态接触区应力呈类高斯分布的理论,利用最小二乘拟合的方法,推导出动态接触区的应力分布函数。通过搭建动静态接触区轮廓提取装置,设计不同下压量下动静态接触区的轮廓提取试验,验证有限元仿真结果的准确性。基于仿真和试验结果推导出动态去除函数,对其进行数值仿真,并与静态去除函数进行对比,发现前者去除率偏小,而且最低点也发生偏移。The dwell time function of the bonnet tool polishing on optics elements is achieved based on static removal function in recent studies.But the polishing tool keeps moving during the process,it's necessary to do the research on dynamic removal function.The static and dynamic contact zone is acquired through finite element simulation analysis,and so is the contact pressure.Both of the contact zones are circle and the size of them are almost the same.The peak point of the dynamic contact pressure has an offset contrary to the direction of the tool movement compared to the static contact pressure.The dynamic contact pressure distribution function is deduced by using the least square method based on the theory that the static pressure distribution function is a modified Gaussian function.The device which can extract both the dynamic and static contact zone is set up to capture them on the condition of different offset.Then the simulation results are verified.The dynamic removal function is deduced and numerical simulated based on the forward simulation and experiment results.The removal rate of the dynamic removal function is smaller than the static removal function and its nadir has a deflection compared to the latter.国家自然科学基金(51075343); 厦门市科技计划(3502Z20113007)资助项

Research on the Residual Error Evaluation Method for Deterministic Polishing of Aspheric Optics

研究非球面光学元件确定性抛光中表面残余误差的评价方法。对两种非球面残余误差的评价方法,分别为轴向误差法和法向误差法,进行理论研究。指出非球面的残余误差理论上应使用法向误差法来评价,并提出一种基于轴向残余误差求解法向残余误差的方法,继而对二者进行比较发现两者存在一定的偏差,并且差值从非球面的中心向边缘方向逐渐增大。以气囊抛光和数控小磨头抛光为例,通过试验表明使用轴向误差法评价残余误差,进行确定性抛光引入了不同程度的加工误差,引入的加工误差的大小与非球面光学元件的口径和顶点曲率半径的比值(即“相对孔径“)成正相关,故对于相对孔径较小的非球面光学元件在确定性抛光中可使用轴向误差法替代法向误差法作为残余误差的评价方法,反之,则应使用法向误差法。Residual error evaluation method for deterministic polishing of aspheric optics is studied.Two residual error evaluation methods, which are axis-direction error method and normal error method respectively, are researched theoretically.It's inferred that the residual error of aspheric surface should be evaluated by normal error method.A new approach is proposed to calculate normal direction residual error on the basis of the axis-direction residual error of the aspheric surface.There exists difference between these two kinds of error which increases from the center of the aspheric optic to the edge through the comparison of them.Taking bonnet polishing and numerical controlled small tool polishing as examples, experiments are made to quantitatively prove that using axis-direction error method to evaluate residual error in deterministic polishing would introduce different degrees of processing error.It's found that the processing error is positively correlated with the relative aperture of aspheric optics, which is the ratio of the optic's aperture and vertex's curvature radius.Therefore, it is recommended to use axis-direction error method instead of normal error method as the evaluation method of the residual error during deterministic polishing aspheric optics with relatively small relative aperture; the opposite is the other way around.国家科技重大专项资助项目(2013ZX04006011-206

r DNA sequence analysis and morphological redescription of Empoasca onukii from the tea growing area of Fujian

重新描述了小贯小绿叶蝉的形态结构,尤其是头部色斑、翅脉、腹部内突、下生殖板及其刚毛着生位置,并增加了足部(刺毛列)特征描述。通过PCr技术克隆得到该物种的r dnA序列,包括部分18S(1 843bP)和28S序列(667 bP)以及完整的5.8S(155 bP)、ITS1(3 114 bP)和ITS2序列(1 008 bP)。序列分析表明,18S,5.8S,28S与其他物种间具有90%~95%的序列一致性;而ITS1和ITS2序列变异性非常大。碱基组成比率分析显示ITS1以及ITS2具有AT偏好性,前者A+T占66.0%,后者占65.1%。与亲缘种的比较分析显示ITS1和ITS2具有丰富的多态位点,并且ITS2更适用于近缘种的分子鉴定。The morphological structures of Empoasca onukii,the cephalic splashes,vein,abdominal apodemes,subgenital plate and the arrangement of its bristles,and the characteristics of legs were redescribed,especially the arrangement of spines were added.Ribosomal DNA( r DNA) including partial of 18S( 1 843 bp),28S( 667 bp) and complete 5.8S( 155 bp),ITS1( 3 114 bp),ITS2( 1 008 bp) were isolated by PCR technology.Sequence analysis indicated that 18 S,5.8S and 28 S had high sequence identity( 90%- 95%) with other insects; however,ITS1 and ITS2 showed much variability.The analysis of base composition showed that ITS1 and ITS2 were more preferences for AT( contained 66.0% and 65.1% A + T,respectively).Comparison with the phylogenetic species revealed that ITS1 and ITS2 from E.onukii had rich polymorphic loci and ITS2 was more suitable for molecular identification of closely related species.国家自然科学基金(81171595

Control Techniques of Bonnet Polishing for Free-form Optical Lenses with Precession

针对自由曲面光学元件的加工特点,研究气囊抛光自由曲面光学元件进动运动控制技术,用于求出气囊工具进动过程中两虚拟轴的转角,实现对气囊自转轴空间位置的控制。以气囊自转轴为研究对象,由于自由曲面光学元件上每个点的法线三维坐标都不相同且气囊进动抛光过程中气囊自转轴与工件加工点局部法线夹角不变,提出建立基坐标系和抛光点对应三维空间坐标系的方法,得到抛光过程中气囊自转轴的空间位置变化情况,而后利用旋转坐标变换得到气囊抛光进动运动控制模型;在所建立的自由曲面光学元件气囊抛光进动运动控制模型中加入控制算法,求出抛光自由曲面光学元件各点时气囊工具两个虚拟旋转轴的转角。利用MATlAb对自由曲面光学元件不同方向截面进行仿真抛光试验,得到自由曲面各方向上气囊抛光进动运动曲线以及仿真进动角曲线,结果证明了自由曲面光学元件气囊抛光进动运动控制模型及控制算法的正确性。Control techniques of bonnet polishing free-form optical lenses with 'precession' is studied,according to the processing characters of free-form optical lenses,to figure out the rotating angles of two virtual axes of bonnet tool,which lead to the controllability of spin axis of bonnet tool.The spin axis of bonnet tool is taken as the object,due to the difference of the local normal of each polishing point and the angle between the spin axis of bonnet tool and local normal is keeping constant in polishing process,a method about how to set up basic coordinate and corresponding coordinate of polishing point is proposed,aiming to get the positions of spin axis of bonnet tool in polishing process,by which a movement model can be obtained by combining with rotating coordinate transformation;Then control algorithm is added to the movement model,and rotating angles of two virtual axes of bonnet tool when polishing each point on free-form optical lenses are calculated.At the end,simulations in polishing different directions of free-form optical lens in Matlab are carried out,to get the curves of precession control and the simulated precession angles,the results reveal that the movement model and control algorithm presented are both correct.国家自然科学基金(51075343); 厦门市科技计划(3502Z20113007)资助项

算子广义逆在最优控制和解算子方程问题上的应用

学位：工学硕士院系专业：数学科学学院信息与计算数学系_计算数学学号：LIM0000012