齿条—齿轮连杆机构的运动综合

本文应用复数法给出了齿条—齿轮四杆机构的运动综合（函数生成、再现轨迹和运动生成）方程，研究了该机构的多任务综合问题，并用连续法求解综合方程组。文中给出了数值实例，求出了满足多任务设计要求的全部机构，并进一步考虑曲柄存在、运动干涉等实际约束问题，对综合所得机构进行了优选。     

平面连杆机构近似综合的连续—优化法

本文将连续法与优化法相结合，以平面铰链四杆机构函数综合为例，研究了平面连杆机构的近似综合问题，得到了能近似实现给定运动条件的多个机构方案，使机构运动综合的多方案优选成为可能。本文工作为平面及空间机构的近似综合研究开辟了新途径。     

连续法在机构运动综合中的应用

介绍连续法的基本理论，编制了通用求解软件，然后应用该方法对平面铰链四杆机构五位置刚体导引综合问题进行了研究，求出了满足给定运动要求的机构所有尺寸方案，并对其进行了优选。本文方法具有一般性，可以用于其它平面机构以及空间机构的运动综合研究。     

平面四杆机构近似导引综合的优化--混沌方法

将优化方法与混沌迭代算法相结合，以平面铰链四杆机构的近似导引综合为例，研究了平面连杆机构的近似导引综合问题的优化一混沌方法，得到了能近似实现给定运动条件的多个机构方案，使机构运动综合的多方案优选成为可能。     

平面连杆机构近似综合的连续－优化法

本文将连续法与优化法相结合,以平面铰链四杆机构函数综合为例,研究了平面连杆机构的近似综合问题,得到了能近似实现给定运动条件的多个机构方案,使机构运动综合的多方案优选成为可能。本文工作为平面及空间机构的近似综合研究开辟了新途径。     

平面连杆机构近似综合的混沌-优化方法

将混沌迭代算法与优化方法相结合 ,以平面铰链四杆机构的函数综合为例 ,研究了平面连杆机构的近似综合问题 ,得到了能近似实现给定运动条件的多个机构方案 ,使机构运动综合的多方案优选成为可能。本文的工作为平面及空间机构的近似综合研究开辟了新途径     

含四杆机构单元的重载转运机器人构型综合

针对用于轴类物料抓取及卸载的重载转运机器人机构形式单一、转运范围局限大等问题,进行了重载转运机器人新构型的研究。首先分析了重载转运机器人机构的结构特点和工作原理,发现含有四杆机构单元的重载转运机器人具有灵活性高、承载能力大等优势,为构型综合和新方案优选提供依据。其次基于图论对只含转动副的平面机构进行构型综合,得到七杆、九杆机构拓扑胚图,利用胚图插点法对拓扑胚图进行插点,建立拓扑图,进而转化成对应的运动链,得到构型图谱。然后根据重载转运机器人机构中的四杆机构单元和功能构件,对拓扑图进行特定化标记,提出重载转运机器人优选条件,分析和优选特定化标记的拓扑图,得到其最佳构型。最后,利用Adams软件对一种优选机构进行仿真分析,结果表明,该机构在平面运动过程中可以同时实现远距离抓取和大范围俯仰运动,从而验证了该机构构型设计的合理性。     

平面四杆机构近似运动综合的自适应方法

给出了具有二次鞍点意义的近似圆点、近似滑点和近似束点的新定义,提出了简单曲　线的自适应拟合方法和法向误差的统一评价模型,建立了平面四杆机构运动不变量优化综合　的统一数学模型和通用的鞍点规划求解方法。将实现给定位置、轨迹和函数的多种类型平面　四杆机构的近似尺度综合全部归结为寻求相对运动平面上的近似圆点、近似滑点和近似束点　及其组合问题,并在理论上阐明了平面四杆机构运动综合问题存在最优近似解和收敛性算法　。     

机构综合的牛顿优化迭代混沌方法研究

将基于混沌的牛顿优化迭代方法与机构学综合理论相结合,把机构学综合的非线性方程组转化为优化问题,然后构造排斥二周期点方程,通过逆像迭代求得排斥二周期点ZJ,利用点集ZJ出现的混沌分形特性求出机构综合的全部解。以平面铰链四杆机构的函数综合为例,研究了平面连杆机构的综合问题,得到了能实现给定运动条件的多个机构方案,使机构运动综合的多方案优选成为可能。本文的工作为平面及空间机构的综合与近似综合研究开辟了新途径。     

铰链四杆机构近似导向综合的完全解

应用优化连续法，研究了铰链四杆机构的近亿讯向综合问题，得到了能近似满足给定导向要求的全部机构方案，并对其进行了优选，此方法具有一般性，可用于其它机构所似运动综合的完全解研究。     

<Emphasis Type="Bold">CNC Rake Grinding for a Taper Ball-End Mill with a Torus-Shaped Grinding Wheel</Emphasis>

A new grinding method using a torus-shaped grinding wheel and a machining path generation method with a novel moving coordinate system are proposed. With this new grinding method, the smooth spiral rake surface of a taper ball-end mill with constant helical angle and constant normal rake angle can be formed during one grinding process and the normal rake angle can be obtained accurately. The novel moving coordinate system is established based on taking account of both the cutting edge curve and the cutter body surface. By means of the novel moving coordinate system, the machining path generation becomes very simple. The proposed grinding method and the machining path generation method are verified by 3D simulation results.     

可任意调节的拉普拉斯网格生成方法

提出采用网格调节项来修正拉普拉斯网格生成方法。算例表明，本文的网格生成方法既可以消除拉普拉斯网格有时产生畸变、有时向曲线边界堆聚的缺陷，又可进行局部网格加密或稀疏，从而为数值计算提供一种实用而有效的网格生成方法。     

Walking pattern generation employing DAE integration method

A stable walking pattern generation method for a biped robot is presented in this paper In general, the ZMP (zero moment point) equations, which are expressed as differential equations, are solved to obtain a stable walking pattern However, the number of differential equations is less than that of unknown coordinates in the ZMP equations It is impossible to integrate the ZMP equations directly since one or more constraint equations are involved in the ZMP equations To overcome this difficulty, DAE (differential and algebraic equation) solution method is employed The proposed method has enough flexibility for various kinematic structures Walking simulation for a virtual biped robot is performed to demonstrate the effectiveness and validity of the proposed method The method can be applied to the biped robot for stable walking pattern generation     

Grind-free tool path generation for five-axis surface machining

This paper discusses automatic tool path generation for five-axis filleted end mill finish-surface machining. A new method of automatic five-axis tool path generation is introduced called Grind-Free (GF) tool path generation. GF surfaces result from tool paths that avoid gouging and have scallops that are within the surface profile or waviness tolerances. New algorithms are presented for determining tool forward step and tool path step-over that produce a GF surface. Gouge-free tool paths can be generated directly from CAD data based solely on local and global machining constraints. The proposed methodology for GF tool path generation has been implemented in the C language using the CODE/Robline system. Surfaces were machined on a Boston Digital 505 five-axis milling machine to confirm this method.     

锥面砂轮磨齿机的等粗糙度磨削法

提出了采用变速展成原理的锥面砂轮等粗糙度磨齿法,该方法可使齿面理论粗糙值处处相等,与通用的匀速展成磨齿法相比,可显著减小理论粗糙度值或缩短磨齿时间。     

Solution region synthesis method of planar one-dof six-bar linkages for specifying 4-positions of a 3R open chain

This paper addresses the synthesis problem of one-dof six-bar linkage motion generation for four precision points. A novel and convenient synthesis approach is introduced. With our method, a 3R chain that guides the movement of its end-effector through a set of four specified task positions is given. We then attach two RR links to this 3R chain to obtain a six-bar linkage. Motion generation can produce an infinite number of solutions for four desired positions. It is difficult for designers to synthesize defect-free linkages and synthesize the best linkage through rapidly and precisely selecting curve points that satisfy every design condition. To solve this problem, a solution region method is given in this paper. With this method an infinite number of mechanism solutions can be expressed on a coordinate plane. In addition, the paper still puts forward a distinguishing method for testing circuit and branch defects for Watt-I six-bar linkages. The feasible mechanism solution regions without any defects are obtained by using the solution region method.     

Heat energy harvesting by utilizing waste heat with small temperature differences between heat source and sink

In this review work, energy harvesting methods for waste heat with small temperature differences between heat source and sink are discussed. At present, many methods are tried and employed to utilize this type of waste heat. A typical example is found in a conventional power generation system. By utilizing this type of waste heat, additional energy can be produced in regular power generation systems. Up to this point, two energy harvesting methods have been introduced and applied for the use with this type of waste heat. One is a method using an organic Rankine cycle (ORC) while the other is a method using a thermoelectric generation (TEG). An ORC is a Rankine cycle that can be applied to this type of waste heat using organic fluids such as refrigerants as working fluids instead of water used in a typical Ranking cycle. On the other hand, a TEG utilizes Peltier, Seebeck, and Thomson effects caused by the temperature difference between the heat source and sink for energy harvesting. In this work, various aspects associated with the use ORC and TEG for waste heat harvesting with small temperature differences between the heat source and sink.

     

Numerically Controlled Machining of Freeform Curves Using Biarc Approximation

To machine a shape incorporating freeform curves, the free-form curves must be approximated and represented in a form suitable for numerically controlled (NC) tool-path generation. Instead of the commonly used line segment approximation, a new method using biarc approximation is presented here. The purpose is to reduce sudden changes in tool movement and increase continuity and smoothness. A biarc can be described as two consecutive circular arcs with an identical tangent at the connecting point. Therefore, tangent continuity can be maintained. Furthermore, curvature continuity can be improved if the difference between the two curvatures is minimised. In this research, biarc segments are used to approximate the freeform curves by controlling the largest deviation distance between the curves and the biarcs. The test results show that the biarc approximation method generates fewer tool-path segments than the traditional line approximation. The definitions of the biarcs are used to generate NC tool paths. A new tool-path generation method is developed for processing rough cutting and finish cutting paths. Example parts modelled with B-spline curves are tested and machined.     

新型游动坐标法及其在复杂形状刀具数控磨削中的应用

通过分析复杂形状刀具的几何角度和数控磨削工艺 ,提出一种新型游动坐标系的刀位计算方法 ,应用该方法可简便地进行复杂形状刀具数控磨削的刀位计算 ,并可实现复杂形状刀具几何角度的精确磨削。通过三维仿真及实际磨削加工试验验证了该刀位计算方法的实用性。     

摆动从动件圆柱凸轮数控加工

阐述了摆动从动件圆柱凸轮廓形曲面的特殊性及由此带来的加工困难;在分析摆动件滚子运动规律以及凸轮槽成型方法的基础上,介绍了利用VB直接生成数控代码的具体步骤.所生成代码可输入四轴联动加工中心用于凸轮加工,使该类凸轮的制造效率、精度、及智能化程度大为提高.