RESEARCH ON ZERO CLEARANCE CYCLOID BALL TRANSMISSION

ＲＥＳＥＡＲＣＨＯＮＺＥＲＯＣＬＥＡＲＡＮＣＥＣＹＣＬＯＩＤＢＡＬＬＴＲＡＮＳＭＩＳＳＩＯＮＱｕＪｉｆａｎｇＡｎＺｉｊｕｎＹａｎｓｈａｎＵｎｉｖｅｒｓｉｔｙＡｂｓｔｒａｃｔ：Ｔｈｅｓｔｅｅｌｂａｌｌｔｒａｎｓｍｉｓｓｉｏｎｏｆｚｅｒｏｇｅａｒｃｌｅａ...     

ANALYSIS AND RESEARCH OF COMPUTER-AIDED MODEL OF HIP JOINT BASED ON REVERSE ENGINEERING

Former research work about the modeling of hip joint focus on the upper segment of femoral, and assumes the acetabulum cup is sphere concave, and the acetabulum prostheses is semisphere. A method of acquiring the point data on the surface of the hipbone using the reverse engineering technology is presented. After analyzing the acetabulum surface fitting error, a rotation ellipsoid CAD model is applied to fit the acetabulum surface, and then optimization technique is used to find the geometric parameters of the model. The fitting error between the sphere and rotation ellipsoid is compared and gets the result that the fitting error of rotation ellipsoid is smaller than sphere, and the rotation ellipsoid can describe the shape of the acetabulum better.     

齿轮系统动态传递误差和振动稳定性的数值研究

建立了计及轮齿时变啮合刚度、啮合阻尼、支承刚度和阻尼的齿轮系统扭转-横向振动耦合的3自由度动力学模型。用数值仿真方法,研究了重合度、支承刚度、啮合阻尼和支承阻尼对齿轮动态传递误差和动力稳定性的影响。研究结论对于高速、精密齿轮传动的动力学设计具有积极意义。     

ROBOT＇S MOTION ERROR AND ONLINE COMPENSATION BASED ON FORCE SENSOR

Robot's dynamic motion error and on-line compensation based on multi-axis force sensor are dealt with.It is revealed that the reasons of the error are formed and the relations of the error are delivered.A motion equation of robot's termination with the error is established,and then,an error matrix and an error compensation matrix of the motion equation are also defined.An on-line error's compensation method is put forward to decrease the displacement error,which is a degree of millimeter,shown by the result of simulation of PUMA562 robot.     

基于GPS的圆度、圆柱度误差数字化计量方法研究

基于对数字化计量过程中关键操作技术的研究,给出圆度、圆柱度误差计量的操作算子构成策略及选用原则,并针对传统的几何误差评定中随意性大、评定参数单一、效率低下等不足,提出现代几何误差计量中以"高效、规范"为目标的多元化评定思想.并通过实例说明该数字化计量思想的运作模式及其工程价值,进一步明确基于GPS(geometrical product specification)的数字化计量方法对于实现误差评定的数字化、规范化和高效化是至关重要的,同时,对于促进国家(际)标准的发展及有效应用也具有十分重要的意义.     

MODELING METHOD FOR PRODUCT STRUCTURE MAPPING BASED ON REVERSE SOLVING OF LOCUS AND MOTION

Aiming at the problem of structure design in reverse-design of mechanism, a structure mapping method based on reverse solving of locus and motion (RSLM) is presented. The mechanism scheme meeting the requirements of geometric and structural features is obtained through RSLM. The element instance subsets related to component are established based on the element type mapping, pair structure type mapping and design knowledge mapping between components and elements layer by layer. The assembly position mapping of elements is established based on the topological structure information of mechanism scheme, and the product modeling of structure mapping is realized. The algorithm program and prototype system of product structure mapping based on RSLM are developed. Application samples show that the method implements the integration of scheme design, assembly design and structure design, and modeling for product structure mapping based on RSLM. The feasibility of assembly is analyzed in scheme design that contributes to reducing the design error, and raising the design efficiency and quality.     

机器人力控制系统稳定性分析及振动抑制

利用Ｌａｇｒａｎｇｅ动力学方程对普通机器人和ＭＡＣＲＯ／ＭＩＣＲＯ组合式机器人两种力控制系统的稳定性进行了分析，分析表明后者更稳定。由于ＭＡＣＲＯ机器人结构动态和力传感器动态的影响，组合式机器人在高频时存在着共振与反共振，为了提高系统的高频性能，提出了一种优化粘性阻尼系数的方法，结果表明，当驱动力为０．５Ｎ时，采用此方法可以使机器人与环境的接触力的变化范围由０．１９～１．１２Ｎ减小为０．４４～０．５０Ｎ。     

搅拌摩擦焊径向阻力的动态测量与分析

利用压力传感器对聚氯乙稀塑料搅拌摩擦焊时搅拌头受到的径向阻力进行动态测量,对引起搅拌头径向阻力变化的原因及相关因素的影响规律进行分析.结果表明,搅拌摩擦焊过程开始后,径向阻力要经过一个先急剧上升,达到峰值后又迅速下降,到某一定值后稳定下来的过程.在其他条件不变的前提下,仅提高搅拌头的旋转速度使径向峰值阻力和稳态阻力都下降,达到峰值和稳态阻力的时间都缩短;仅提高焊接速度使峰值阻力大幅度上升,而稳态阻力却有升有降,但幅度不大,达到峰值阻力的时间变化不大,而达到稳态阻力的时间延长;搅拌头直径的变化会同时引起摩擦发热功率和散热功率的变化,它对径向阻力的影响比较复杂.     

考虑阀口误差的阀控非对称液压缸系统建模、仿真与试验

从解决比例阀控制非对称缸系统存在的超压问题入手,分析因加工误差引起的各阀口重叠量不一致这一非线性因素对系统性能的影响,建立考虑阀口误差的阀控非对称缸系统的非线性状态方程模型和键图模型。应用这两种非线性数学模型分析一实际非对称阀控制非对称缸系统的压力特性,与试验结果的对比分析验证了所建的非线性数学模型的正确性。仿真和试验研究揭示比例阀控制非对称缸系统的阀口误差对系统性能影响较大,往往是引起有杆腔压力超过供油压力的主要原因。通过大量仿真研究获得了阀口误差与系统超压之间的关系,研究表明适当提高比例阀阀口的加工精度有利于消除超压现象和提高系统的性能,进而建议将某些比例阀阀口误差控制在最大阀位移的0.5%以内。给出的两种非线性数学模型具有通用性,可用于对各类阀控缸系统进行系统仿真、设计和控制策略等方面的理论研究工作。     

高精度RV传动的受力分析及传动效率

为了给新型ＲＶ传动的优化设计提供科学依据，论述了其原理和特点，提出了该传动名义力分析计算模型并给出了计算实例，最后进行了效率分析计算。     

THEORETICAL ANALYSIS AND EXPERIMENTAL STUDY OF CARBON NANOTUBE PROBE AND CONVENTIONAL ATOMIC FORCE MICROSCOPY PROBE ON SURFACE ROUGHNESS

In this paper, three different tips are employed, i.e., the carbon nanotube tip, monocrystalline silicon tip and silicon nitride tip. Resorting to atomic force microscope （AFM）, they are used for measuring the surface roughness of indium tin oxide （ITO） film and the immunoglobulin G （IgG） proteins within the scanning area of 10 μm×10 μm and 0.5 μm×0.5 μm, respectively. Subsequently, the scanned surface of the ITO film and IgG proteins are analyzed by using fractal dimension. The results show that the ffactal dimension measured by carbon nanotube tip is biggest with the highest frequency components and the most microscopic information. Therefore, the carbon nanotube tip is the ideal measuring tool for measuring super-smooth surface, which will play a more and more important role in the high-resolution imaging field.     

综合传动装置变速机构振动频率与敏感度分析

为了避免综合传动装置在扭转振动时发生共振，需要对传动装置的结构参数进行重新设计、修改。一个复杂的传动装置中，修改哪些结构参数才能有效地改变系统的固有频率是不易确定的。文中建立某综合传动系统的多自由度质量－弹性－阻尼动力学模型，根据复模态振动理论求解该系统在某一挡位下的振动模态，并进行振动频率对系统结构参数的敏感度分析，从33个结构参数中选出4个进行修改，可以有效地改变系统的固有频率。