应用内置传感器信号的工业机器人末端运动特性检测方法研究

工业机器人作业过程中末端运动特性对加工质量有着重要影响。其关节运动特性在一定程度上决定了机器人末端的运动精度和运动特性。提出一种基于工业机器人内置传感器信号的检测方法。工业机器人关节电机的内置传感器信号能够实时反映关节运动信息,通过关节运动信息可以对机器人末端的运动特性进行检测和评估。经过与球杆仪的对照试验和负载、速度变化对末端运动特性的影响实验,验证了该方法的可行性和有效性,能够方便、快捷地实现工业机器人作业过程中末端运动特性的检测。     

箱型钢结构轨道式焊接机器人D-H模型与连续轨迹规划

针对箱型钢的结构特征和焊接过程特点,设计了一款5自由度的轨道式焊接机器人,用于箱型钢结构安装现场的自动化焊接. 采用D-H法,建立了机器人运动学模型,并通过特定的代数方法进行了逆运动学求解,推导出了焊枪末端的空间位姿参数与焊接机器人各关节变量的解析关系模型. 在此基础上,采用连续路径运动的轨迹规划法,在给定焊枪末端轨迹时,对各关节的运动情况进行了MATLAB仿真研究. 结果表明,导出的逆运动学求解模型可用于箱型钢结构焊接机器人的连续运动轨迹和姿态规划和控制,为实施机器人的运动控制奠定了基础.     

基于正交双目视觉的研磨工具位姿引导方法

为解决Eye-in-Hand的自主研磨作业机器人在完全未知的非结构化环境中,能够感知作业空间的三维信息、识别作业空间中的目标及该目标与研磨工具末端的位姿等问题,提出一种基于正交双目视觉实时反馈研磨工具末端的位姿并引导其实时运动的方法。将视觉传感器的测量坐标系(待加工曲面坐标系)建立在对应的激光平面上,并将两个正交相机的光轴交点作为引导研磨工具末端位姿的参考点,从该参考点开始迭代逐步逼近实际加工点。对两个正交相机采集的图像进行处理,可以得到研磨工具末端在两个相机图像坐标系的位置和姿态,再对两组正交立体位置信息进行融合得到其三维位姿。实验结果表明:利用两个正交CCD相机构成的Eye-in-Hand结构能够实时反馈和引导研磨工具末端三维位姿,提供了通过机器视觉引导机器人进行待加工曲面轮廓研磨的解决方案。     

沉井基础取土作业机器人设计与研究

针对传统沉井基础施工设备取土效率低、地层适应性较差、作业区域存在盲区等问题，设计一款沉井基础取土作业机器人。结合施工需求，对机器人进行结构设计，并对其伸缩臂进行有限元静力学分析，验证了伸缩臂结构设计的合理性和可靠性；基于D-H法和几何法分别建立了机器人正、逆运动学模型，基于几何法建立了机器人关节空间到驱动空间的运动学模型，将铣挖头位姿控制最终转换为各关节液压驱动器的位置控制；设计了机器人关节驱动电液比例控制系统，采用PID控制器对其进行校正，通过仿真验证了控制策略的有效性；通过现场试验对机器人整机使用性能进行分析。试验结果表明：沉井基础取土作业机器人满足沉井施工需求，达到预期目标。     

双机器人协同焊接的轨迹优化

提出一种双机器人协同焊接轨迹优化方法.基于弗莱纳-雪列矢量理论,建立并修正复杂焊缝离散点坐标系.在双机器人协同焊接有效工作空间内,以最佳焊位、焊接速度恒定、无碰撞以及一定焊枪工作位姿为约束条件,确定双机器人初始焊接点可行域.基于焊接平稳性思想,以焊接全过程双机器人各关节角位移变化总量最小化为优化目标,获取最优初始焊接点和其对应的最优焊接轨迹.搭建试验平台,比较最优初始焊接点和其它可行点的协同焊接轨迹.对各关节的平均角速度、角速度波动性、峰值和焊接时间四个方面分析.结果表明,提出轨迹优化方法是有效的.     

基于NURBS算法的工业机器人轨迹规划研究

轨迹规划是工业机器人研究领域的重要内容之一。为解决使用直线与圆弧逼近不规则曲线方法带来较大误差的问题,提出使用NURBS拟合自由曲线,并使用S形速度曲线来控制机器人末端的运动速度和加速度,使各个插补点的位置、速度和加速度能够连续,将之反推到关节空间可以得到各个关节的角度、角速度和角加速度。最后以IRB2600工业机器人为仿真本体,通过MATLAB仿真证明:NURBS和S形速度曲线相结合的方法可以得到在关节空间连续、平稳的运行轨迹、速度曲线、加速度曲线,减弱了因各关节角度、角速度、角加速度突变带来的冲击影响,优化了机器人运行轨迹。     

光伏板清洁机器人运动学建模与仿真

为实现光伏板清洁机器人的精准运动控制,运用D-H法建立光伏板清洁机器人臂架机构运动学数学模型。根据变量的性质,将光伏板清洁机器人臂架机构的运动学问题用驱动空间、关节空间、位姿空间之间的映射关系描述,根据机构的几何特征,分别推导出各工作空间之间的映射关系。在MATLAB环境下对臂架机构数学模型进行运动学仿真并绘制清洗装置末端轨迹包络图,验证光伏板清洁机器人臂架机构运动学数学模型的正确性。研究结果为光伏板清洁机器人轨迹规划、运动仿真与动力学分析等提供了理论依据。     

基于几何不变性和滑动模态算法的冗余机器人运动控制研究

冗余机器人可以通过冗余自由度实现额外的优化目的。针对受空间约束条件下机器人运动控制问题,采用几何不变性和滑动模态算法,实现冗余机器人的有效控制,并对控制效果进行仿真验证。通过建立冗余机器人系统数学模型,给出冗余机器人轨迹跟踪典型控制方案,优化了冗余机器人控制目标。设计推导出能确保机器人关节位置向量在约束空间内,且冗余机器人关节能平滑到达约束边界的几何不变性和滑动模态算法。采用数学软件MATLAB对平面3R冗余机器人系统进行仿真。同时,与不采用文中算法的计算结果进行对比和分析。仿真结果显示:冗余机器人关节在受到外部约束时,采用几何不变性和滑动模态算法所有关节能保持在约束空间内,同时关节能够平滑地接近约束边界,关节误差在3.2 s就能够快速收敛。     

机器人作两圆柱相贯线运动的一种轨迹规划方法

针对作两圆柱相贯线运动的机器人提出了一种有效的轨迹规划方法；用作图法完成了空间位姿的描述，减少了因解代数方程而带来的大量计算，使位姿的描述形象、明了；利用运动学方程完成笛卡尔坐标空间与关节坐标空间的相互转换；利用变角速度实现稳定的运动效果；在比较多种插值函数的基础上，对关节变量作了多项式插值；提出了计算算法及具体情况的解决方法，并作了综合分析。     

基于导航路径约束的多模块柔性检测机器人运动规划研究

连续体机器人运动规划复杂且控制精度低是制约其深入研究和快速应用的重要难题。基于几何分析法对连续体机器人进行运动学建模研究，构建关节空间与末端笛卡尔空间的映射模型，在此基础上对其工作空间进行分析。为满足柔性检测机器人在狭小空间的快速介入和准确探测需求，提出一种基于导航路径约束的机器人运动规划方法，以连续体机器人各弯曲单元前后端点与理想轨迹间的最小距离作为目标函数，通过逆向递推的方法逐节求出各弯曲单元关节参数，从而控制机器人沿着预设导航路径进行介入运动。最后分别通过平面C形弯曲曲线和空间路径的运动规划仿真实验对所提路径规划算法进行验证，同时研究该规划方法下机器人关节长度及单元个数变化时机器人的跟随效果。仿真结果表明：所提运动规划方法能够有效控制连续体机器人沿着预设路径进行介入运动，并具有较高的控制精度和较强的适应性。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

THERMODYNAMICS STUDY ON THE DECOMPOSITION OF CHROMITE WITH KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

INFLUENCE OF HEAT TREATMENT ON DAMPING BEHAVIOUR OF THE MAGNESIUM WROUGHT ALLOY AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Theoretical Analysis for the Motion and Temperature of Melt Droplets in Spray Degassing Process

The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.     

An Easy Way to Quantify the Adhesion Energy of Nanostructured Cu/X(X=Cr,Ta,Mo,Nb,Zr) Multilayer Films Adherent to Polyimide Substrates

An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films(NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be *5.0 J/m2 for Cu/Cr, *4.1 J/m2 for Cu/Ta,*2.8 J/m2 for Cu/Mo, *1.1 J/m2 for Cu/Nb, and *1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.     

High-Speed Friction Stir Welding of SiC_p/Al–Mg–Si–Cu Composite

A 17 vol% SiCp/Al–Mg–Si–Cu composite plate with a thickness of 3 mm was successfully friction stir welded(FSWed) at a very high welding speed of 2000 mm/min for the first time. Microstructural observation indicated that the coarsening of the precipitates was greatly inhibited in the heat-affected zone of the FSW joint at high welding speed, due to the significantly reduced peak temperature and duration at high temperature. Therefore, prominent enhancement of the hardness was achieved at the lowest hardness zone of the FSW joint at this high welding speed, which was similar to that of the nugget zone. Furthermore, the ultimate tensile strength of the joint was as high as 369 MPa, which was much higher than that obtained at low welding speed of 100 mm/min(298 MPa). This study provides an effective method to weld aluminum matrix composite with superior quality and high welding efficiency.     

A STUDY OF TEMPERATURE-DEPENDENT VALENCE BOND STRUCTURE OF TITANIUM

On the basis of energy and shape method for the determination of the valence bond (VB) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is e_c~(2.9907) · (s_c~(0.4980) d_c~(2.4927)) ef1.0093 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。