整体式风电叶片紫外光原位固化纤维铺放制造技术

针对风电叶片树脂传递模塑制造工艺自动化程度低,劳动强度高,质量不稳定等问题,提出整体式风电叶片自动化制造新方法,该方法将紫外光原位固化工艺和自动纤维铺放技术相结合以实现整体式风电叶片的制造。根据风电叶片前后缘存在极大曲率的外形特点,提出过渡线轨迹生成算法以获得完整的初始铺放轨迹信息。通过CATIA CAA软件二次开发实现前后缘处铺放轨迹自动生成,以解决极大曲率风电叶片铺放路径生成问题。通过分析整体式叶片芯模的制造方案,并进行整体式风电叶片紫外光原位固化纤维铺放成形基础试验,验证了所提出整体式风电叶片自动纤维铺放制造方法是可行的。该方法能够使预浸带沿任意角度铺放,并通过铺缠在芯模上完整的预浸带铺层来代替分片式叶片中的胶层,有利于提高整体式叶片的综合性能。为了进一步提高紫外光原位固化纤维铺放工艺所制备的复合材料层合板的性能,高质量光固化预浸带的研制需要尽快开展。     

复合材料自动铺带技术现状与研究进展

复合材料已成为新一代飞机机体的主体结构材料,复合材料低成本制造技术是目前国际复合材料技术领域的核心问题之一,自动铺带技术作为复合材料成型自动化的典型代表,已成为飞机复合材料翼面壁板技术的标准,大飞机项目已经立项,自动铺带技术必将成为我国提高飞机复合材料用量的一项关键技术。本文对自动铺带装备的基本构成、铺放工艺原理与自动铺放技术的发展历程、工业应用现状、发展趋势进行了较全面的介绍与讨论,最后展望了自动铺带技术在我国的发展前景。     

机器人运动学和动力学的几何表示及其应用

应用现代微分几何的方法，分别将二自由度机器人的轨迹弧长和动能定义为黎曼度量指标。对黎曼曲面上的测地线和黎曼曲率进行了定量分析，利用曲面上的测地线和黎曼曲率的几何性质，提出基于测地线的最优轨迹规划方法和基于黎曼曲率的工作空间优化方法，并以平面2R机器人为例进行了实例计算。     

Mastercam_X6在异形构件纤维铺放中的应用

基于Mastercam_X6,利用其数控多轴加工技术,将切削加工转化为复合材料成型铺放技术,通过将刀具的运动轨迹转化为铺丝头纤维铺放轨迹,进行异形截面零件的纤维铺放成型,实现数控自动铺放过程。试验以飞机襟翼的纤维铺放为例,针对异形截面,特别是含有凹曲面的制件,进行了铺丝头轨迹规划及创建、加工方式的对比选择、仿真加工、后置处理和NC程序输出,实现了数控多轴加工技术在异形截面纤维铺放上的成功应用,并对如何运用Mastercam软件实现复杂曲面的多轴纤维铺放作了对比探讨。     

复杂曲面自动铺丝轨迹规划算法设计

针对复杂曲面自动铺丝轨迹生成问题,提出一种可自动生成铺丝轨迹的经线包络法,即按照曲面形态,自适应生成一族包络整个曲面的经线,然后以此作为参考线,根据复合材料铺丝束纤维的宽度、数量等工艺数据,生成与对应参考线成固定铺放角度的铺丝轨迹。该算法适用于采用参数方法描述的复杂曲面,仿真实例表明该算法可行且有效。     

复合材料加工机床

复合材料加工机床是目前先进复合材料数字化制造的技术热点。复合材料的自动铺放机床主要分为纤维缠绕机床和自动铺放机床2种,自动铺放机床再可分为自动铺带机床和自动纤维铺放机床2种。描述了各种复合材料加工机床的结构以及纤维束的加热和切割、纤维丝束的输送、纤维铺放和紧压3项技术难点,介绍了模块化铺带头、纤维铺放机器人2项技术的发展趋势。     

复合材料加工机床

复合材料加工机床是目前先进复合材料数字化制造的技术热点。复合材料的自动铺放机床主要分为纤维缠绕机床和自动铺放机床2种,自动铺放机床再可分为自动铺带机床和自动纤维铺放机床2种。描述了各种复合材料加工机床的结构以及纤维束的加热和切割、纤维丝束的输送、纤维铺放和紧压3项技术难点,介绍了模块化铺带头、纤维铺放机器人2项技术的发展趋势。     

碳纤维螺旋桨自动铺放成形轨迹规划方法

螺旋桨曲面为高阶自由曲面，故以四丝束碳纤维螺旋桨曲面铺放装置为平台，进行了碳纤维铺放成形轨迹规划的研究。依据船用定距桨桨叶曲面轨迹规划的要求，针对传统曲面网格和轨迹铺放法的低精度缺陷，提出了基于拉普拉斯网格优化、等弧长曲面分层的轨迹优化铺放算法，并完成了算法仿真和实物验证。结果表明，该轨迹规划方法能满足碳纤维螺旋桨的铺放要求。     

变角度自动铺丝制造缺陷特性及影响因素的研究进展

自动铺丝作为一种先进的复合材料自动化成型技术被广泛应用于航空航天等领域,其中采用变角度自动铺丝能够提升航空航天结构件的设计空间,对于提高构件整体力学性能具有重要的意义。但目前该技术的加工工艺并不成熟且在成型过程中不可避免产生制造缺陷,对构件的力学性能带来不利的影响。针对变角度自动铺丝成型过程中的制造缺陷特性及其主要影响因素进行综述,介绍了自动铺丝的工作原理及变角度铺丝的优势,分析了褶皱、间隙和重叠缺陷的形成机制及其对变刚度层合板力学性能的影响,深入探讨了变角度铺丝制造缺陷的影响因素类型及作用机理,并论述了制造缺陷的抑制方法,最后总结了现阶段变角度自动铺丝技术存在的不足,并对该技术的未来研究趋势进行了展望。     

龙门式复合材料自动铺丝机研发设计

先进复合材料具有高比强度、抗疲劳、耐腐蚀、设计制造一体化的特点,其在飞机上的用量和应用部位已经成为衡量飞机结构先进性的重要标志之一,而用于制造复合材料整体构件的自动铺丝设备成为现代飞机制造的关键设备。按照铺放16纤维丝束的要求,开发了具有自主知识产权的龙门式自动铺丝设备。     

Automated tool trajectory planning of industrial robots for painting composite surfaces

Automatic trajectory generation for spray painting is highly desirable for today’s automotive manufacturing. Generating paint gun trajectories for free-form surfaces to satisfy paint thickness requirements is still highly challenging due to the complex geometry of free-form surfaces. In this paper, a CAD-guided paint gun trajectory generation system for free-form surfaces has been developed. The system utilizes the CAD information of a free-form surface and a paint gun model to automatically generate a paint gun trajectory to satisfy the paint thickness requirements. Complex surfaces are divided into patches to satisfy the constraints. A trajectory integration algorithm is developed to integrate the trajectories of the patches. The paint thickness deviation from the required paint thickness is optimized by modifying the paint gun velocity. A paint thickness verification method is also developed to verify the generated trajectories. The results of simulations have shown that the trajectory generation system achieves satisfactory performance. This trajectory generation system can also be applied to generate trajectories for many other CAD-guided robot trajectory planning applications in surface manufacturing.     

面向铣削加工的STEP-NC文件到G代码转换技术

为使STEP-NC能在传统的数控系统中得到应用,研究了面向铣削加工的STEP-NC数控文件到传统G代码程序的转换技术,提出了一种面向制造特征的刀具轨迹规划方法。首先对制造特征进行分类,然后为每类制造特征设计走刀轨迹模型,在进行G代码转换时,通过前置处理将制造特征的走刀轨迹模型转换成对应数控系统的宏程序,不但提高了G代码的转换效率,而且缩短了G代码程序的长度。论述了STEP-NC文件信息提取和信息处理技术,以及G代码程序自动转换过程。最后,以一个铣削类零件为例,对上述技术进行了测试和验证。     

Toward autonomous mining: design and development of an unmanned electric shovel via point cloud-based optimal trajectory planning

With the proposal of intelligent mines, unmanned mining has become a research hotspot in recent years. In the field of autonomous excavation, environmental perception and excavation trajectory planning are two key issues because they have considerable influences on operation performance. In this study, an unmanned electric shovel (UES) is developed, and key robotization processes consisting of environment modeling and optimal excavation trajectory planning are presented. Initially, the point cloud of the material surface is collected and reconstructed by polynomial response surface (PRS) method. Then, by establishing the dynamical model of the UES, a point to point (PTP) excavation trajectory planning method is developed to improve both the mining efficiency and fill factor and to reduce the energy consumption. Based on optimal trajectory command, the UES performs autonomous excavation. The experimental results show that the proposed surface reconstruction method can accurately represent the material surface. On the basis of reconstructed surface, the PTP trajectory planning method rapidly obtains a reasonable mining trajectory with high fill factor and mining efficiency. Compared with the common excavation trajectory planning approaches, the proposed method tends to be more capable in terms of mining time and energy consumption, ensuring high-performance excavation of the UES in practical mining environment.     

面向特征库的整体叶轮刀轨规划方法

针对整体叶轮曲面曲率变化大、流道为特殊型腔的特点,提出了一种面向特征的刀轨规划方法。分析了整体叶轮加工型面的特征及加工难点,建立由叶片、流道、进出水边、叶根等不同型面刀轨构成的特征库。设计叶轮加工型面与特征刀轨库间的匹配规则,开发了整体叶轮加工型面特征刀轨规划系统。算例仿真表明,该方法可有效减少叶轮加工曲面的刀路数量,提高整体叶轮自由曲面叶片的加工质量和效率。     

A Surface Based Approach for Constant Scallop HeightTool-Path Generation

The machining of sculptured surfaces such as moulds and dies in 3-axis milling relies on the chordal deviation, the scallop height parameter and the planning strategy. The choice of these parameters must ensure that manufacturing surfaces respect the geometrical specifications. The current strategies for machining, consist primarily in driving the tool in parallel planes which generates a tightening of the tool paths. A constant scallop height planning strategy has been developed to avoid this tightening. In this paper, we present a new method of constant scallop height tool-path generation based on the concept of the machining surface. The concept of the machining surface is developed and its use to generate constant scallop height tool paths is described. The approach is compared with existing methods in terms of precision and in particular its aptitude to treat curvature discontinuities.     

Trajectory optimization of an electro-hydraulic robot

The electro-hydraulic robot has great driving torque and plays an irreplaceable role in manufacturing. In this paper, a trajectory planning method for a 6-DOF electro-hydraulic robot based on time-energy-jerk is proposed and realized. A multi-objective function of the electro-hydraulic robot about working efficiency, impact, stability and energy consumption factors was built, at the same time, the kinematic and dynamic constraint functions were also built. The multi-objective trajectory function of the robot was optimized by using the non-dominated neighborhood immune genetic algorithm, and the optimal position, velocity, acceleration and jerk planning curves of each joint were obtained. In the experiment, the flow output curves of the hydraulic system of joint 6 based on fuzzy-PID control strategy under no-load, 1.5 kg load, 4 kg load were obtained, and show that the velocity and position trajectory of the joint can be well controlled using the presented fuzzy PID control strategy.

     

基于转向架姿态轨迹的轨道线路曲率探测系统研究

主动径向技术是进一步提高轨道车辆曲线通过性能、彻底解决直线运行稳定性和曲线通过之间矛盾的有效途径,而实现轨道线路曲率准确、高效的探测是其中的重要环节。为了提高轨道线路曲率探测的精度和实时性,首先提出了一种基于转向架姿态轨迹的曲率探测系统(Bogie attitude trajectory based curvature detection system,BATCDS),该系统由布置于转向架上的速度传感器、角速度传感器、倾角传感器以及算法单元组成,布局简单且易于实现。此后,提出了与上述系统相匹配的曲率探测算法,该算法利用转向架偏航角速度ω和车速v获取转向架在二维水平面上的运行轨迹,并据此初步估计线路曲率;利用转向架侧滚角α和车速v获取转向架的侧滚姿态轨迹,进而估计转向架侧滚角;综合转向架上述各项姿态信息,利用轨道线路固有几何规律融合计算线路曲率。最后,建立了BATCDS的联合仿真模型,仿真计算的结果表明,该系统在有效滤除原始信号中的高频噪声的基础上,仍能维持较高的实时性;仿真工况下,相较传统的低通滤波而言曲率探测结果的精度和实时性得到显著改善,相对误差率均降低至传统方法的50%以下,最大...