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基于可操作性指标的6R操作臂型综合方法 总被引:1,自引:1,他引:0
串联操作臂的性能不但与拓扑结构,而且与尺度参数密切相关,在研究拓扑选型时有必要考虑尺度参数对其运动学性能的影响。提出一种包含拓扑结构和尺度参数的6R串联操作臂构型优选方法。通过枚举相邻关节轴线的可能组合得到6种构型,构造出一种位于中间轴线连体坐标系下的速度雅可比矩阵通用算法,并对上述各种拓扑构型分别构造包含结构参数的雅可比矩阵及其行列式,以使雅可比矩阵行列式为零的结构参数数目最小,且所包含正交轴线关系最多为构型优选评价指标。据此综合出一种符合上述优选指标的构型。利用该方法综合出的6R串联操作臂构型具有灵活度好、便于电动机装配、且折叠性好等优点。 相似文献
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针对空间4R冗余度机械臂活动关节工作空间进行了定量研究,并且对其容错空间做了进一步探讨。首先推导出空间4R冗余度机械臂不同关节锁定时工作空间的解析表达式,并且根据表达式对工作空间进行了三维造型;然后,进一步分析了机械臂的D-H参数对工作空间的影响;最后,给出3 sigm a型机械臂容错空间的计算方法及三维造型,分析了其容错空间的影响因素。研究结果表明:当机械臂结构参数一定时,一个活动关节(关节2)在一定范围内锁定,工作空间不变,并且此锁定范围与结构参数一一对应;机械臂的臂长之和一定时,各机械臂长度越接近,机械臂的工作空间越大;机械臂关节2偏置的存在使机械臂工作空间不会出现薄壳,另一活动活动关节(关节3)的偏置的存在也可以增大工作空间;关节工作空间增大,容错空间也会相应增大。 相似文献
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提出了1种并联机构工作空间的几何求解及尺度优化方法。首先,借助闭环矢量法构造了线性驱动6自由度并联机构的位置逆解模型;推导得出并联机构定姿态可达工作空间的边界曲面方程,获得精确的3维可达空间;提出"有效工作空间比"概念,以刻画可达工作空间的有效尺度域;最后,在考察归纳机构关键尺度参数对有效工作空间比的影响规律的基础上,以包络已知任务空间的可达空间体积最小作为目标函数,结合有效工作空间比取值范围、驱动关节位移范围、构件干涉及尺度约束等约束条件,联合应用模拟退火+模式搜索算法进行了机构关键尺度参数的优化设计。研究成果可为并联机构的结构设计奠定必要理论基础。 相似文献
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采用一种球坐标变步长迭代快速搜索算法,分析求解了一种3T1R并联机构的可达工作空间,并用天牛须搜索算法对其机构尺寸进行了优化设计。首先,对机构进行位置分析,得到其运动学逆解;然后,采用一种球坐标变步长迭代快速搜索算法求解得到了该3T1R并联机构的可达工作空间,并以工作空间体积大小为衡量指标,定量分析了并联机构各结构参数对工作空间体积的影响;最后,以工作空间体积最大值为目标,利用天牛须搜索算法对并联机构结构参数进行了优化,得到了最优值。该求解算法运算步骤少,求解速度快,为此类并联机构的实际应用提供了理论依据。 相似文献
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A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load. 相似文献
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针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。 相似文献
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针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。 相似文献
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交通荷载作用下桥梁结构参数识别方法 总被引:2,自引:1,他引:1
应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别. 相似文献
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The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci... 相似文献
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针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。 相似文献
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RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication. 相似文献
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For robot interaction control,the interaction force between the robot and the manipulated object or environment should be monitored.Impedance control is a type ... 相似文献
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CHEN Guangyuan DU Libin HE Haijing LEI Zhuo WU Chengxuan ZHANG Qisheng 《Instrumentation》2015,(2):18-27
This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%. 相似文献
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ZHOU Jianfeng GU Boqin 《机械工程学报(英文版)》2007,20(6):54-61
In order to investigate the sealing performance variation resulted from the thermal deformation of the end faces, the equations to calculate the fluid film pressure distribution, the bearing force and the leakage rate are derived, for the fluid film both in parallel gap and in wedgy gap. The geometrical parameters of the sealing members are optimized by means of heat transfer analysis and complex method. The analysis results indicate that the shallow spiral grooves can generate hydrodynamic pressure while the rotating ring rotates and the bearing force of the fluid film in spiral groove end faces is much larger than that in the flat end faces. The deformation increases the bearing force of the fluid film in flat end faces, but it decreases the hydrodynamic pressure of the fluid film in spiral groove end faces. The gap dimensions which determine the characteristics of the fluid film is obtained by coupling analysis of the frictional heat and the thermal deformation in consideration of the equilibrium condition of the bearing force and the closing force. For different gap dimensions, the relationship between the closing force and the leakage rate is also investigated, based on which the leakage rate can be controlled by adjusting the closing force. 相似文献