基于多粒度共进化功能能推理的机械运动方案设计新方法

提出了基于多粒度共进化功能推理的机械运动方案设计方法.首先分析了共进化功能推理模型和多粒度设计模型的特点,并结合二者的优点构造了一种多粒度的共进化功能推理模型;然后将该推理模型应用于机械运动方案设计,提出了一种面向机械运动方案设计的共进化功能推理方法,该方法采用分类功能来描述机构单元及机械系统的运动特征信息,将机构单元和机械系统都采用运动功能变换函数进行抽象表达,通过功能推理来生成机械运动变换单元的串联组合方案;随即给出了相应的功能推理算法流程,通过与已有算法的比较详细分析了该算法的特性,并讨论说明了该算法所具有的效率高、可精确描述运动功能变换特性等优点;最后通过电线进给机构运动方案设计实例验证了该方法的有效性.     

数字式光栅测长仪温度测量定标系统

为满足数字式光栅测长仪测量精度进一步提高的需要,为数字式光栅测长仪测温系统设计制作了一种高精度多路温度定标系统。根据热传导理论,分析了系统设计的合理性。同时通过实验检测证实了该系统的实用性。该系统具有成本低、精度高、操作方便、易于在现场推广应用等优点。用该系统定标的多路温度测量仪送法定计量部门检定,检定结果表明该系统达到预定的标准。     

Transmission Index Research of Parallel Manipulators Based on Matrix Orthogonal Degree

Performance index is the standard of performance evaluation, and is the foundation of both performance analysis and optimal design for the parallel manipulator. Seeking the suitable kinematic indices is always an important and challenging issue for the parallel manipulator. So far, there are extensive studies in this field, but few existing indices can meet all the requirements, such as simple, intuitive, and universal. To solve this problem, the matrix orthogonal degree is adopted, and generalized transmission indices that can evaluate motion/force transmissibility of fully parallel manipulators are proposed. Transmission performance analysis of typical branches, end effectors, and parallel manipulators is given to illustrate proposed indices and analysis methodology. Simulation and analysis results reveal that proposed transmission indices possess significant advantages, such as normalized finite (ranging from 0 to 1), dimensionally homogeneous, frame-free, intuitive and easy to calculate. Besides, proposed indices well indicate the good transmission region and relativity to the singularity with better resolution than the traditional local conditioning index, and provide a novel tool for kinematic analysis and optimal design of fully parallel manipulators.     

套管扶正器位移检测系统下位机设计

本文详细介绍了套管扶正器位移检测系统下位机部分的设计过程,包括增量式编码器的选用及其原理介绍、位移量显示与PC机通信等电路的设计和软件的编制。本系统采用精度很高的增量式编码器,选用通用外围电路,硬件结构简单,软件编程容易实现,测量精度高,可在其它短距离、高精度的位移测量中推广。     

化妆品自动装盒机取盒-开盒机构的设计与仿真

通过对化妆品装盒机取盒-开盒机构的分析,研究了实现内摆线运动轨迹的行星轮式取盒-开盒机构。确定了两旋转中心距离和吸头半径等关键参数对取盒效率的影响,建立了数学模型,分析了机构运动的速度和加速度,利用Matlab软件对机构中的吸头的运动轨迹、位移、速度、加速度进行仿真并绘制出相应的曲线,为机构的优化提供理论依据。最终设计出能够实现高取盒效率的取盒机构。该机构有易于制造、运行平稳、结构紧凑等特点。     

Practical and intuitive controller design method for precision positioning of a pneumatic cylinder actuator stage

The present paper describes a practical and intuitive controller design method for precision positioning of pneumatic cylinder actuator stages. Pneumatic actuators are easy to use and have numerous advantages, which has led to these actuators having a wide variety of applications. However, pneumatic actuators have notable nonlinear characteristics, which make precision positioning difficult to achieve. The purpose of the present study is to clarify a practical and intuitive controller design procedure for precision positioning of a pneumatic cylinder actuator. In addition to positioning performance, the present study focuses on the realization of easy controller design without the need for the exact model parameters or knowledge in control theory for general-industrial-use pneumatic cylinder actuators with friction characteristics. These considerations are important in order to fully exploit the advantages of pneumatic cylinder actuators in a wide variety of applications. As such, three elements are added to the conventional continuous-motion nominal characteristic trajectory following (CM NCTF) controller. A new design procedure of the improved CM NCTF controller for pneumatic cylinder actuator stages is introduced, and the positioning performance of the designed control system is examined experimentally under several conditions. The positioning results generally indicate a positioning error of 50 nm, which is equal to the sensor resolution.     

Backward-motion control of a mobile robot with n passive off-hooked trailers

A passive multiple-trailer system provides various practical advantages for multi-functional service robots. However, motion control is difficult because the kinematic model is highly nonlinear. The kinematic design of a trailer system was proposed in prior research of ours. In this paper, it is shown how the backward motion of a robot with n passive trailers can be controlled. Once the desired trajectory of the last trailer is computed, the control input of the pushing robot is obtained through the proposed control scheme. Some experimental issues on reversing the trailer system are addressed. This paper provides an answer to the following question: “Does the system work well even if there are sensing or modeling errors?” Although it is difficult to obtain general analytic solutions for the above research question, a practical answer will be explored though simplified analysis and experiments. Experimental verifications are carried out using a mobile robot with three passive trailers. The experimental results show that backward-motion control can be successfully carried out by applying the proposed control scheme.     

6R操作臂逆运动学分析与轨迹规划

提出一种依赖初始位形的6R串联操作臂运动学逆解模型与轨迹规划方法。以折叠状态下6R串联操作臂各关节轴线方向单位矢量和位置矢量为基础,运用旋量理论与指数积方法建立该操作臂在初始状态下的运动学模型,以解析法得到该操作臂的16组运动学逆解,通过规划末端执行器在全局坐标系下的位置和姿态运动轨迹,应用运动学逆解得到各关节的运动轨迹。仿真结果表明该操作臂运动学模型、逆解方法与轨迹规划结果正确。该方法建立的6R串联操作臂运动学模型及逆解方法具有建模简单、易于求解、便于轨迹规划等优点。     

Optimal dynamic design of anthropomorphic robot module with redundant actuators

In this paper, a study on the optimal dynamic design for an anthropomorphic robot module with redundant actuators is performed. Musculoskeletal structure of human body is a typical example of redundantly actuated mechanism, and provides superior features than general robotic mechanisms. An anthropomorphic robot module that resembles the structure of human upper limb is introduced to utilize the advantages of redundant actuation system. Optimal dynamic design of the proposed robot module that follows optimal kinematic design is carried out to maximize the advantages. Five design indices are introduced, which are associated with inertia matrix, inertia power array representing nonlinear terms and gravity terms of the dynamic modeling equation. A concept of composite design index based on max-min principle of fuzzy theory is employed to deal with multi-criteria based design. As a result of dynamic optimization, a set of dynamic parameters, representing optimal mass distribution of the manipulator is obtaind. It is shown that the dynamic optimization yields a notable enhancement in dynamic performances, as compared to the case of kinematic optimization only.     

基于试验与仿真联合分析的喷涂机器人轨迹精度可靠性研究

采用链驱动的喷涂机器人易于实现本体的轻量化、末端高灵活度与正压防爆系统设计,从而满足家具、钢结构等一般涂装行业对喷涂机器人工作空间与腕部灵活度的要求,深入分析链驱动机器人的运动可靠性对喷涂质量和效率的提高具有重要意义。针对链驱动喷涂机器人的运动可靠性问题,采用一种基于试验与仿真联合分析的机器人末端轨迹精度可靠性分析方法。以旋量法为基础建立了喷涂机器人本体和喷枪的运动学模型,从工业机器人的操作臂性能和运动规律的角度出发,研究了喷涂机器人运动精度的影响因素。分析了链驱动喷涂机器人的优缺点和末端轨迹精度的影响状况,并结合机器人本体的运动学参数,建立了基于随机变量的喷涂机器人运动误差模型。通过试验结果的分析来确定影响喷涂机器人运动误差的随机变量的分布特征,从而对机器人末端轨迹精度的运动可靠性进行更加精确的仿真分析。最后,通过喷涂机器人工作平台对末端轨迹精度的运动误差进行试验验证并与传统的仿真分析方法进行对比,结果显示该分析方法更准确。研究成果为进一步分析喷涂机器人的机构优化、轨迹规划和漆膜质量提供试验基础和理论依据。     

机载主被动一体化微波探测仪结构设计与分析

利用机载主被动一体化微波探测仪进行土壤湿度的探测对高精度土壤水分反演具有重要意义。文中根据探测任务需求以及机载试验复杂的力学振动环境和温度环境,开展了探测仪的结构设计,并对系统结构开展了力学仿真分析和热设计,验证了结构设计的合理性。经过机载校飞试验的实际考核,样机满足机载环境使用要求,探测仪系统工作正常。该探测仪结构具有布局紧凑、精度高、工作稳定、安装方便等优点,可为同类机载校飞载荷的结构设计提供参考。     

虚拟现实系统头盔与数据手套的三维精确定向与定位系统与设计

讨论了一种新型的基于超声波测距的高精度三维定痊定向系统的原理与设计。这种三维定位定向系统采用波头计数与零交叉点检测的方法来提高超声波测距精度,并通过三角形方法来实现三点所在平面的位置与姿态。     

Higher-order continuation method for the rigid-body kinematic design of compliant mechanisms

Compliant mechanisms are of great interest in precision engineering. In this paper, we propose a higher-order continuation method to help their rigid-body kinematic design. The method helps to investigate the choice of a mechanism configuration through the whole exploration of the workspace, and eases the kinematic analysis to avoid, or take advantage of, the vicinity of kinematic singularities. Such approach is relevant for planar and quasi-planar mechanisms that can be obtained with micro-manufacturing processes adapted to precision applications. The higher-order continuation method allows for a direct and accurate plotting of the input–output relationship of any mechanism by considering only its geometrical closed-loop equations, i.e. without the complex derivation of any analytical model. We show that these plots, called bifurcation diagrams, reveal essential information such as the joint velocity profile and the presence of singular configurations. Moreover, the continuous and accurate computation of the mechanism configuration in the vicinity of singularities provides detailed information about the kinematic behavior of the mechanism in its extreme positions. For the design of compliant mechanisms, the designer can advantageously use the bifurcation diagrams to evaluate the relevance of the selected mechanism, then to identify a configuration in order to obtain desired kinematic properties without the derivation of the inverse kinematic model (IKM) or the direct kinematic model (DKM). The method is exemplified with a 3 universal-joint and 3 spherical-joint mechanism (3-US), the IKM and DKM of which cannot be derived analytically. The latter has a large workspace and special kinematic behaviors consisting of a screw-like motion and a platform gyration, which have not been studied before and could lead to novel compliant devices.     

Automatic Design Theory and Realization of Kinematic Schemes for Mechanism System

Based on an analysis of mechanism combination methods of a current mechanism system kinematic scheme, input/output kinematic behavior and their constraint relations were proposed to represent the kinematic behavior knowledge of a mechanism system. Furthermore, a tree structure of a kinematic behavior decomposition process for a mechanism system was provided. Considering multiple outputs for a mechanism system, the matching algorithm and the attributes propagation method of kinematic behavior were used to generate a mechanism combination scheme. Its intermediate design solution and the constraint relations between input and output are generated to fill the common blackboard. Moreover, using information in the blackboard as input motion, the behavior attributes of other process actions are transmitted to attribute items of the blackboard, which finally enables a computer-aided automatic design process of a mechanism system kinematic scheme. To avoid the problem of schemes combination explosion caused by unbounded depth in the search process, bounded depth-first search was used to control the number of expanded hierarchies for a design tree. Finally, an example was given to show its feasibility and solution efficiency. Translated from the Journal of Shanghai Jiaotong University, 2004, 38(6) (in Chinese) This work was supported by the National Natural Science Foundation of China (grant 59875058)     

多关节测量臂的小生境混沌优化校准

多关节测量臂是一种便携式的坐标测量设备,它由一系列的旋转关节组成。为了提高多关节测量臂的测量精度和可重复性水平,必须对其运动学参数进行校准。首先,利用小生境的混沌优化算法提出了一种新的运动学校准方法以及一种混合目标的运动学校准函数,它考虑了诸如单点测量实验、容积性测量实验等多种性能测量实验的实验结果,然后,采用Levenberg Marquardt(L-M)算法和小生境混沌优化算法应用于运动学参数校准。小生境混沌优化算法显示出了优于L-M算法的性能。实验结果表明:使用NCOA算法校准后,测量误差的标准差始终优于LMA算法,并且校准前后多关节测量臂的测量精度提高了40倍。采用L-M算法和小生境混沌优化算法应用于运动学参数校准。小生境混沌优化算法显示出了优于L-M算法的性能。     

2自由度高速高精度并联机器人的运动学优化设计

提出一种基于工作空间综合和灵巧度、速度和几何精度等性能指标分析的2自由度并联机器人运动学优化设计方法,构造一种由灵巧度、运动速度和运动分辨率等变量组合而成的工作空间全局评价指标。优化过程分为两步进行：首先以灵巧度、力传递特性和避免奇异位形的几何条件为约束,综合出具有良好特性的工作空间,在此基础上研究不同杆长比下实现目标工作空间所需的尺度参数;然后根据全局运动学性能评价指标从第一步的优化结果中遴选出最合适的杆长比,从而实现了对机构的几何尺度参数优化。并给出了算例以说明方法的有效性。     

数控研磨机研磨去除量的在线监控系统试验研究

将光栅测量系统和数控技术用于高速研磨机上,从而给研磨机增加监控功能,这是新型高速研磨机的发展方向。光栅测量系统具有数字化、精度高和安装方便等优点,故选用光栅测量系统测量压头的位移,并利用计算机实现相应的控制。介绍了光栅测量系统的组成、工作原理及主要技术参数,并对数控研磨机监控装置的组成和监控原理进行了分析,对高速研磨机的设计优化具有参考价值。     

锡膏印刷机印刷系统的误差分析与补偿

为了减小或消除全自动视觉锡膏印刷机的印刷系统误差,在介绍了锡膏印刷机系统的组成和功能的基础上,通过分析运动机构产生系统误差的原因和作用过程,针对平台运动机构误差做了定量分析,并对平台运动机构进行了误差测试,根据测试得到的结果数据,设计了一种减小印刷系统误差的补偿方案。实验结果表明,对印刷系统的误差测试与分析是合理的,所建立的印刷系统的误差模型准确可靠,对运动精度的分析和实际生产装配有一定的指导意义。     

基于DSP的双闭环可逆PWM直流调速系统设计与实现

以DSP微处理器为核心的直流调速系统具有调速精度高、稳定性好和调试过程容易等优点。本设计采用TI公司的TMS320LF2407A芯片作为主控制器,和其它外围电路一起,来完成集电机调速、保护、报警和转速在线监测与显示等多功能在一起的直流电机调速系统设计。