基于游离磨料的机器人抛光工艺实验研究

建立了基于游离磨料和软质抛光工具的工业机器人抛光系统,研究了机器人抛光轨迹的生成方法,并研究了主要工艺参数如主轴转速、轨迹间距和机器人行走速度对表面抛光质量的影响,为确定合理的机器人抛光工艺参数提供了依据。在此基础上对等离子熔射快速制造的金属模具型腔进行了表面抛光实验验证。     

磁性轮式球罐焊接机器人机械结构设计与分析

设计制造了一种磁性轮式球(储)罐焊接机器人,对其机械结构及动作过程进行了分析和说明.实验和实践证明,该机器人能安全可靠地行走于球(储)罐内外表面的任意位置,完全适用于球罐、储罐及大直径管道的自动焊接,使焊接质量和焊接速度大幅度提高.     

基于等离子熔射成形技术的快速模具制造

提出利用等离子熔射成形技术快速制造模具，以镍基合金粉末NiO1(Ni-Fe-Cr-B-Si）为熔射材料进行快速制模实验研究，详细介绍了其技术特点及工艺过程，讨论了相关的关键技术问题。     

机器人制造陶瓷原型系统的研究

提出了采用工业机器人快速制造陶瓷熔射原型的方法。利用建立的数字化检测平台,测试机器人的点位置重复精度、直线轨迹位置精度和轨迹重复精度,找到其精度特性;建立NC代码与机器人代码的转换公式,得到了生成合适的机器人铣削路径代码的算法和CAM软件;根据机器人的精度特性和合适的加工路径,实际加工了用于熔射制模的陶瓷型熔射原型,验证了机器人制造系统的可行性。     

等离子熔射快速制模中机器人运动轨迹生成方法及实践

在机器人等离子熔射快速制模中,熔射轨迹对熔射皮膜的成形性有重要影响。本文提出了由CAM加工轨迹转化为机器人等离子熔射轨迹的方法,避免了以往通过STL文件生成机器人熔射轨迹的繁琐过程。文章重点介绍了如何将CAM加工轨迹转化为机器人熔射轨迹,并对其进行了仿真与实验验证,结果表明:该方法比原有的由STL文件生成机器人熔射轨迹的方法更简便、灵活,更适应机器人等离子熔射制模成形的要求。     

熔射快速制造汽车、摩托车覆盖件模具

介绍熔射高熔点材料快速制造汽车、摩托车覆盖件模具的工艺过程,对原型制作、熔射参数及工艺、加衬补强的材料及工艺进行了探讨,并对该方法制造的模具进行了评估。研究结果表明,以熔射不锈钢粉末形成的熔射层为工作层,以树脂基复合材料为补强材料,通过熔射层的转移与补强材料结合而制作的模具,具有表面硬度高、质量好、经济耐用、制作简单等特点,适用于汽车、摩托车等新产品试制及改型换代、中小批量生产,具有应用前景。     

架空电力线绝缘漆自动喷涂行走机器人设计

目前的架空电力线采用人工喷涂的方式,存在着效率低、速度慢、喷涂绝缘层不均匀等缺陷,现设计能够在高空行走并对架空电力线实现自动喷涂绝缘漆的机器人。该机器人以PLC为控制核心,通过无线传输与地面HMI通信,能够在架空电力线上自动行走,采用模糊控制策略调节机器人行走速度和绝缘漆喷涂量,实现特定厚度的绝缘漆自动喷涂作业。该系统已成功应用于广西电力电网系统,通过运行发现该系统设计合理、运行可靠、喷涂均匀,在自动喷涂过程中实现了全自动化和智能化。     

机器人辅助模具自动抛光研究及发展趋势

因为模具抛光已成为模具智能制造的“瓶颈”,故模具自动抛光的研究已引起广泛的关注,并取得了很大的进展。概述了机器人辅助模具自动抛光研究的进展;介绍了关节式PUMA－562机器人为平台的辅助模具自动抛光实验系统,提出了进一步的研究方向。     

面向连杆模具的混联机器人柔性抛光系统开发

为了解决连杆模具抛光过程中人工抛光时间长、劳动强度大等问题,建立了一套混联机器人柔性抛光系统。在该系统上对材料去除模型进行了研究,建立了考虑抛光工具磨损的材料去除模型,能够良好预测一定抛光参数下的材料去除量;在此基础上,对模具型腔表面自动分片,并使用UG和示教相结合的方法生成加工轨迹;根据模具抛光力的控制需要,建立了一套气动控制系统,使用自主设计的浮动恒力抛光主轴结合PID控制算法实现了恒力抛光。最后在该柔性抛光系统上进行了汽车连杆模具抛光实验,实验结果表明了该柔性抛光系统能够较好地完成连杆模具抛光任务,得到较好的抛光效果。     

整体叶轮机器人研磨柔顺控制研究

针对目前整体叶轮人力手工研磨过程中研磨品质差、出产周期长、工人健康危害大等问题,开发了一套基于六自由度库卡工业机器人的自动研磨控制系统.机器人末端夹持气动磨机贴合整体叶轮表面,利用六维力传感器反馈受力情况,结合在线恒力控制算法搭建复杂曲面机器人研磨恒力控制系统.根据机器人运动学理论,对机器人研磨过程中末端加工工具重力干扰进行补偿;建立机器人力/位置混合柔顺控制策略,采用传统PID控制策略进行基础力控制,采用模糊自适应PID控制策略进行优化力控制实现机器人自动研磨.对整体叶轮进行研磨实验,结果表明模糊自适应PID控制算法可以有效的实现机器人的柔顺控制,保持研磨过程接触力在有效范围内.     

机器人精加工陶瓷原型技术的路径规划研究

研究了机器人精加工陶瓷原型技术的路径规划方法.生成四种加工路径方案,对比分析了采用这些加工路径得到的精度和效率,提出一种合理的机器人精加工陶瓷原型路径设计方案.根据此方案生成加工路径,实际加工了用于熔射制模的陶瓷原型,其精度及表面质量均满足熔射要求,验证了该加工路径方案的可行性.     

Designing and Optimization of an Off-line Programming System for Robotic Belt Grinding Process

Off-line programming (OLP) system becomes one of the most important programming modules for the robotic belt grinding process, however there lacks research on increasing the grinding dexterous space depending on the OLP system. A new type of grinding robot and a novel robotic belt grinding workcell are forwarded, and their features are briefly introduced. An open and object-oriented off-line programming system is developed for this robotic belt grinding system. The parameters of the trimmed surface are read from the initial graphics exchange specification (IGES) file of the CAD model of the workpiece. The deBoor-Cox basis function is used to sample the grinding target with local contact frame on the workpiece. The numerical formula of inverse kinematics is set up based on Newton’s iterative procedure, to calculate the grinding robot configurations corresponding to the grinding targets. After the grinding path is obtained, the OLP system turns to be more effective than the teach-by-showing system. In order to improve the grinding workspace, an optimization algorithm for dynamic tool frame is proposed and performed on the special robotic belt grinding system. The initial tool frame and the interval of neighboring tool frames are defined as the preparation of the algorithm. An optimized tool local frame can be selected to grind the complex surface for a maximum dexterity index of the robot. Under the optimization algorithm, a simulation of grinding a vane is included and comparison of grinding workspace is done before and after the tool frame optimization. By the algorithm, the grinding workspace can be enlarged. Moreover the dynamic tool frame can be considered to add one degree-of-freedom to the grinding kinematical chain, which provides the theoretical support for the improvement of robotic dexterity for the complex surface grinding.     

A simulation platform for optimal selection of robotic belt grinding system parameters

Robotic belt grinding is an effective process for removing material from geometrically complex workpieces. However, due to the relatively low stiffness of the system, the grinding quality is prone to inaccuracies caused by system dynamics. In order to control the quality of the grinding process, a profound understanding of the system is required. This paper presents a platform for comprehensive modeling and simulation of the robotic belt grinding system. The system kinematics model is based on the CAD model of the workpiece in composition with robot kinematics. The dynamics model is a comprehensive combination of the dynamics of the robot, the grinder, and the interaction between the grinder and the workpiece. A material removal model of the grinding process, which can adapt to workpieces with complicated shapes, is also developed and presented. The system simulation shows that optimal selection of key control parameters of the grinder and proper selection of robot control strategies can efficiently suppress chatter in the grinding process. Furthermore, having the ability to predict material removal rate, the comprehensive simulation platform is also demonstrated to be a strong tool in selecting the grinding process key parameters, namely, robotic velocity and contact force, for the control of material removal to meet dimensional accuracy requirements on workpieces.     

叶片机器人砂带磨抛点云匹配算法优化

为解决机器人磨抛路径中工件坐标系难以计算的问题及校正工件装夹误差,将三维点云配准技术应用到叶片机器人砂带磨抛系统中。由三维激光扫描仪扫描工件型面获得工件点云,采用基于主成分分析(PCA)的全局配准算法和改进的迭代最近点(ICP)算法完成了扫描点云和工件模型离散点云间以及不同工件扫描点云间的匹配,以获取工件坐标系和校正工件装夹误差。相关仿真和试验结果表明,优化后的算法在匹配速度与精度上有了长足改进,且加工后产品精度和质量都能满足实际加工要求。     

Trajectory planning for roboticbelt grinding of turbine blade

In order to improve the quality and efficiency of blade grinding, the robot and belt grinding technologies were applied to blade machining, and the characteristics and working procees of the system were introduced. Through the comparison of multi-axial machining trajectory generation technologies, equal chord deviation fitting method and equal scallop height method were adopted to plan the robot traaectory. Because of their shortcomings in blade grinding, these two methods were improved. In order to evaluate the improved methods and compare efects of manual and robotic proceesing, a test was carried out. The experimental results show that, the blade machined by robot has much beter surface quality than that by hand. The relevant experiment validates the eefectivenees of robotic machining and the improved methods. [ABSTRACT FROM AUTHOR]     

Precision grinding of binderless ultrafine tungsten carbide (WC) microstructured surfaces

The primary objective of this study was to produce binderless ultrafine tungsten carbide (WC) microstructured surfaces in the ductile grinding regime and to optimize machining parameters to generate microstructural features and sharp edges without chipping. The micro-deformation, fracture properties, and grinding mechanisms were characterized using micro/nano-indentation and single-grit grinding experiments. The effects of grinding conditions (such as grinding mode, feed rate, and spindle speed) on ground surface quality and the radius and chipping of edges were investigated using microstructural grinding experiments. It was found that in nano-indentation, the binderless WC indentation was accommodated by plastic deformation. An average critical depth of cut of 146 nm could be achieved on single-grit scratching tests using atomic force microscopic procedures. In grinding of microstructured surfaces, the surface roughness of side surfaces was always smaller than that of the bottom surface of the machined feature. The better surface quality and sharper edges were obtained by using the upcut grinding mode. Reducing the tool feed rate did necessarily help to improve the surface roughness and edges of structures. The best ground surface could be obtained at the grinding speed of 2,500 rpm. According to the grinding experimental results, an echelle grating was manufactured using the optimized parameters. The average surface roughness SRa of the bottom surface was 78 nm and that of the side surface was 60 nm. The radius of the edge was less than 1 μm, and the radius of corner was about 3 μm. No visible evidence of grinding-induced cracks and chipping on the ground surfaces was found.     

叶片复杂曲面的机器人抛磨工艺规划

为了实现复杂曲面工件的智能抛磨加工,对叶片复杂曲面进行机器人抛磨工艺规划。对抛磨点位置规划算法和基于最大接触原则的抛磨姿态规划算法进行了研究。首先,通过平行截面法获得抛磨路径割线,以非均匀有理B样条(NURBS)曲线描述。接着,提取曲线特征参数,根据设定的阈值进行抛磨点规划,再基于抛磨轮与工件的最大接触原则进行抛磨点姿态规划,从而得到完整的抛磨路径。然后,将工件位姿从工件坐标系转换到TCP坐标系。最后,搭建了柔性抛磨系统仿真平台生成机器人控制程序。实验结果表明,此方法规划的路径可用于叶片复杂曲面的机器人抛磨加工。分别用本文规划所得路径和CAM软件规划所得路径对叶片进行抛磨加工,测得表面粗糙度分别为0.695~0.930μm和2.803~3.243μm。本文提出的抛磨位姿规划方法可用于复杂曲面工件的抛磨路径规划,使工具和工件保持最大接触,从而避免了位姿不合理所产生的过抛和欠抛。