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两自由度工业机器人 三自由度工业机器人设计篇一
patricia ben-horin和moshe shoham,会员,ieee
摘要
本文研究了奇异性条件大多数的六自由度并联机器人在每一个腿上都有一个球形接头。首先,确定致动器螺丝在腿链中心。然后用凯莱代数和相关的分解方法用于确定哪些条件的导数(或刚度矩阵)包含这些螺丝是等级不足。这些工具是有利的,因为他们方便操纵坐标-简单的表达式表示的几何实体,从而使几何解释的奇异性条件是更容易获得。使用这些工具,奇异性条件(至少)144种这类的组合被划定在四个平面所相交的一个点上。这四个平面定义为这个零距螺丝球形关节的位置和方向。指数terms-grassmann-cayley代数,奇点,三条腿的机器。
一、介绍
在过去的二十年里,许多研究人员广泛研究并联机器人的奇异性。不像串联机器人,失去在奇异配置中的自由度,尽管并联机器人的执行器都是锁着但是他们的的自由度还是可以获得的。因此,这些不稳定姿势的全面知识为提高机器人的设计和确定机器人的路径规划是至关重要的。
主要的方法之一,用于寻找奇异性并行机器人是基于计算雅可比行列式进行的。gosselin和安杰利斯[1]分类奇异性的闭环机制通过考虑两个雅克比定义输入速度和输出速度之间的关系。当圣鲁克和gosselin[2]减少了算术操作要求定义的雅可比行列式高夫·斯图尔特平台(gsp),从而使数值计算得到多项式。
另一个重要的工具,为分析螺旋理论中的奇异性,首先阐述了1900的论文[6]和开发机器人应用程序。几项研究已经应用这个理论找到并联机器人的奇异性,例如,[11]-[14]。特别注意到情况,执行机构是线性和代表螺丝是零投的。在这些情况下,奇异的配置是解决通过使用几何,寻找可能的致动器线依赖[15]-[17]。其他分类方法闭环机制可以被发现在[18]-[22]。
在本文中,我们分析了奇异点的一大类三条腿的机器人,在每个腿链有一个球形接头上的任何点。我们只关注了正运动学奇异性。首先,我们发现螺丝相关执行机构的每个链。因为每一个链包含一个球形接头,自致动器螺丝是相互联合的,他们是通过球形关节的零螺距螺杆螺丝。然后我们使用grassmann-cayley代数和相关的发展获得一个代数方程,它源于管理行机器人包含的刚度矩阵。直接和高效检索的几何意义的奇异配置是最主要的一个优点,在这里将介绍其方法。
虽然之前的研究[53]分析7架构普惠制,各有至少三条并发关节,本文扩展了奇点分析程度更广泛的一类机器人有三条腿和一个球形关节。使用降低行列式和grassmann-cayley运营商我们获得一个通用的条件,这些机器人的奇异性提供在一个简单的几何意义方式计算中。
本文的结构如下。第二节详细描述了运动学结构的并联机器人。第三节包含一个简短的在螺丝和大纲性质的背景下驱动器螺丝,零距螺丝作用于中心的球形关节。第四部分包含一个介绍grassmann-cayley代数的基本工具用于寻找奇异性条件。这部分还包括刚度矩阵(或导数)分解成坐标自由表达。第五节中一个常见的例子给出了这种方法。最后,第六章比较了使用本方法结果与结果的其他技术。
二、运动构架
本文阐述了6自由度并联机器人有六间连通性基础和移动平台。肖海姆和罗斯[54]提供了调查可能的结构,产生基于流动公式6自由度的grubler和kutzbach。他们寻找了所有的可能性,满足这个公式对关节的数目和任何链接。gsp和三条腿的机器人结构的一个子集所列出的6自由度shoham和罗斯。一个类似的例子也证实了了podhorodeski和pittens[55],他发现了一个类的三条腿的对称并联机器人,球形关节、转动关节的平台在每个腿比其他结构潜在有利。正如上面所讨论的,大多数的报告文献限制他们的分析结构和球形关节位于移动平台和棱柱关节作为驱动的关节。在这个分类,我们包括五种类型的关节和更多的可选职位的球形关节。
我们处理机器人有三个链连接到移动平台,每个驱动有两个1自由度关节或一个二自由度关节。这些链不一定是平等的,但都有移动和连接六个基地和之间的平台。除了球形接头(s),关节考虑是棱镜(p),转动(r)、螺旋(h)、圆柱(c)和通用(u),前三个是1自由度关节和最后两个二自由度的关节。所有的可能性都显示在表i和ii。该列表只包含机器人,有平等的连锁,总计144种不同的结构,但是机器人与任何可能的组合链也可以被认为是membersof这类方法。组合的总数,大于500 000,计算方式如下:
三、管理方法
本节涉及螺丝和平台运动的确定。因为考虑机器人有三个串行链,每个驱动器螺丝的方向可以由其互惠到其他关节螺钉固定在链条。被动球形接头在每个链部队驱动器螺丝为零距(行)并且通过它的中心。因此,三个平面是创建中心位于自己的球形关节。
以下简要介绍了螺旋理论,广泛的解决[7],[73],[75];我们解决在第二节中列出相互的所有关节螺钉系统。
上述类的机器人的几何结果奇点现在相比其他方法获得的结果要准确。首先,我们比较奇异条件在上述3 gsp平台与结果报告线几何方法。
根据相对几何条件的他行方法区分不同的几种类型沿着棱镜致动器[81]的奇异性。我们表明,所有这些奇异点是特定情况下的条件通过(17 c)提供,这是有效的三条腿以及6:3 gsp平台的机器人的考虑。这种结构的奇异的配置根据线几何分析包括五种类型:3 c、4 b、4 d,5 a和5 b[17],[36]。
四、奇异性分析
本节确定奇异性条件定义在第二节的机器人。第一部分包括寻找方向的执行机构的行动路线,基于解释第三节中介绍。他行通过球形接头中心,而他们的方向取决于关节的分布和位置。第二部分包括应用程序的方法使用了grassmann-cayley代数在第四节定义奇点。因为每对线满足在一个点(球形接头),所有例子的解决方案是象征性地平等,无论点位置的腿或腿的对称性。我们从文献中举例说明使用三个机器人的解决方案。
1.方向的致动器螺丝
第一个例子是3-prps机器人提出behi[61][见图3(a)]。对于每个腿驱动螺丝躺在这家由球形接头中心和转动关节轴。特别是,致动器螺杆是垂直于轴的,和致动器螺杆是垂直于轴的,这些方向被描绘在图3(b)。第二个例子是the3-usr机器人提出simaan et al。[66][见图4(a)]。每条腿有驱动器螺丝躺在通过球形接头中心和包含转动关节轴中。驱动器螺丝穿过球形接头中心并与转动关节轴相连。这些方向被描绘在图4(b)。
第三个例子是3-ppsp byun建造的机器人和[65][见图5(一个)]。每条腿,驱动螺丝躺在飞机通过球形接头中心和正常的棱镜接头轴。驱动器螺丝垂直于轴的,和致动器螺杆是垂直于轴的,这些方向被描绘在图5(b)。
图3(a)3-prps机器人提出behi[61]
(b)飞机和致动器螺丝
图4(a)3自由度机器人提出simaan和shoham[66]
(b)飞机和致动器螺丝的3自由度机器人
图5(a)3-ppsp机器人提出byun[65]
(b)飞机和致动器螺丝
2、.奇异性条件
雅克(或superbracket)的机器人是分解成普通支架monomials使用麦克米兰的分解,即(16)。解释部分3—b机器人,本文认为每个链有两个零距驱动器螺丝通过球形接头。拓扑,这个描述等于行6:3 gsp(或在[53]),这三条线,每经过一个双球面上的接头平台(见图6)。这意味着每对线共享一个公共点(这些点在图6中)。因此类的机器人被认为是在本文中,我们可以使用相同的标记点的至于6:3 gsp。六线与相关各机器人通过双点,并且,用同样的方式在图6。
图6 6-3 gsp
五、结果
本文提出一个广义奇异性分析并联机器人组成元素。这些是有一个球形接头在每个腿链的三条腿的6自由度机器人。因为球形关节需要驱动器,螺丝是纯粹的力量作用于他们的中心,他们的位置沿链是不重要的。组成元素包括144机制不同类型的关节,每个都有不同的联合装置沿链。提出并建立描述几个机器人出现在列表中。大量的机器人相关的分析组合不同被认为是。奇点的分析是由第一个找到的执行机构使用互惠的螺丝。然后,借助组合方法和grassmann-cayley方法,得到刚度矩阵行列式在一个可以操作的协调自由形式,可以翻译成一个简单的几何条件之后。其定义是几何条件由执行机构位置的线条和球形接头,至少有一个相交点。这个有效的奇异点条件考虑所有组成元素中的机器人。一个比较的结果与结果的奇点证明了其他技术所有先前描述奇异条件实际上是特殊情况下的几何条件的四架飞机交叉在一个点,一个条件获取的方法直接在这里提出。
singularity condition of six-degree-of-freedom three-legged parallel robots based on grassmann–cayley algebra patricia ben-horin and moshe shoham, associate member, ieee
abstract this paper addresses the singularity condition of a broad class of six-degree-of-freedom three-legged parallel robots that have one spherical joint somewhere along each , the actuator screws for each leg-chain are grassmann–cayley algebra and the associated superbracket decomposition are used to find the condition for which the jacobian(or rigidity matrix)containing these screws is tools are advantageous since they facilitate manipulation of coordinate-free expressions representing geometric entities, thus enabling the geometrical interpretation of the singularity condition to be obtained more these tools, the singularity condition of(at least)144 combinations of this class is delineated to be the intersection of four planes at one four planes are defined by the locations of the spherical joints and the directions of the zero-pitch terms—grassmann–cayley algebra, singularity, three-legged uction during the last two decades, many researchers have extensively investigated singularities of parallel serial robots that lose degrees of freedom(dofs)in singular configurations, parallel robots might also gain dofs even though their actuators are ore, thorough knowledge of these unstable poses is essential for improving robot design and determining robot path of the principal methods used for finding the singularities of parallel robots is based on calculation of the jacobian determinant in and angeles [1] classified the singularities of closed-loop mechanisms by considering two jacobians that define the relationship between input and output -onge and gosselin [2] reduced the arithmetical operations required to define the jacobian determinant for the gough–stewart platform(gsp), and thus enabled numerical calculation of the obtained polynomial in ov et al.[3]–[5] expanded the classification proposed by gosselin and angeles to define six types of singularity that are derived using equations containing not only the input and output velocities but also explicit passive joint r important tool that has served in the analysis of singularities is the screw theory, first expounded in ball’s 1900 treatise [6] and developed for robotic applications by hunt [7]–[9] and sugimoto et al.[10].several studies have applied this theory to find singularities of parallel robots, for example, [11]–[14].special attention was paid to cases in which the actuators are linear and the representing screws are these cases, the singular configurations were solved by using line geometry, looking for possible actuator-line dependencies [15]–[17].other approaches taken to classify singularities of closed-loop mechanisms can be found in [18]–[22].in this paper, we analyze the singularities of a broad class of three-legged robots, having a spherical joint at any point in each individual focus only on forward kinematics , we find the screws associated with the actuators of each every chain contains a spherical joint, and since the actuator screws are reciprocal to the joint screws, they are zero-pitch screws passing through the spherical we use grassmann–cayley algebra and related developments to get an algebraic equation which originates from the rigidity matrix containing the governing lines of the direct and efficient retrieval of the geometric meaning of the singular configurations is one of the main advantages of the method presented the previous study [53] analyzed only seven architectures of gsp, each having at least three pairs of concurrent joints, this paper expands the singularity analysis to a considerably broader class of robots that have three legs with a spherical joints somewhere along the the reduced determinant and grassmann–cayley operators we obtain one single generic condition for which these robots are singular and provide in a simple manner the geometric meaning of this structure of this paper is as n ii describes in detail the kinematic architecture of the class of parallel robots under n iii contains a brief background on screws and outlines the nature of the actuator screws, which are zero-pitch screws acting on the centers of the spherical n iv contains an introduction to grassmann–cayley algebra which is the basic tool used for finding the singularity section also includes the rigidity matrix(or jacobian)decomposition into coordinate-free section v a general example of this approach is y, section vi compares the results obtained using the present method with results obtained by other tic architecture this paper deals with 6-dof parallel robots that have connectivity six between the base and the moving and roth [54] provided a survey of the possible structures that yield 6-dof based on the mobility formula of grübler and searched for all the possibilities that satisfy this formula with respect to the number of joints connected to any of the gsp and three-legged robots are a subset of the structures with 6-dof listed by shoham and roth.a similar enumeration was provided also by podhorodeski and pittens [55], who found a class of three-legged symmetric parallel robots that have spherical joints at the platform and revolute joints in each leg to be potentially advantageous over other discussed above, most of the reports in the literature limit their analysis to structures with spherical joints located on the moving platform and revolute or prismatic joints as actuated or passive additional ions are the family of 14 robots proposed by simaan and shoham [28] which contain spherical-revolute dyads connected to the platform, and some structures mentioned below which have revolute or prismatic joints on the this classification, we include five types of joints and more optional positions for the spherical deal with robots that have three chains connected to the moving platform, each actuated by two 1-dof joints or one 2-dof chains are not necessarily equal, but all have mobility and connectivity six between the base and the s the spherical joint(s), the joints taken into consideration are prismatic(p), revolute(r), helical(h), cylindrical(c), and universal(u), the first three being 1-dof joints and the last two being 2-dof the possibilities are shown in tables i and list contains only the robots that have equal chains, totaling 144 different structures, but robots with any possible combination of chains can also be considered as membersof this total number of combinations, , is larger than 500 000, calculated as follows:
ing lines this section deals with the screws that determine the platform the robots under consideration have three serial chains, the direction of each actuator screw can be determined by its reciprocity to the other joint screws in the passive spherical joint in each chain forces the actuator screws to have zero-pitch(lines)and to pass through its ore, three flat pencils are created having their centers located at the spherical ing a brief introduction to the screw theory that is extensively treated in [7], [73]–[75];we address the reciprocal screw systems of all the joints listed in section geometric result for the singularity of the aforementioned class of robots is now compared with the results obtained by other approaches in the , we compare the singularity condition described above for the 6-3 gsp platform with the results reported for the line geometry line geometry method distinguishes among several types of singularities, according to the relative geometric condition of he lines along the prismatic actuators [81].we show that all these singularities are particular cases of the condition provided by(17c), which is valid for the three-legged robots under consideration as well as for the 6-3 gsp singular configurations of this structure according to line geometry analysis include five types: 3c, 4b, 4d, 5a, and 5b [17], [36].arity analysis this section determines the singularity condition for the class of robots defined in section first part consists of finding the direction of the actuator lines of action, based on the explanation introduced in section lines pass through the spherical joint center while their directions depend on the distribution and position of the second part includes application of the approach using grassmann–cayley algebra presented in section iv for defining singularity when considering six lines attaching two every pair of lines meet at one point(the spherical joint), the solution for all the cases is symbolically equal, regardless of the points’ location in the leg or the symmetry of the exemplify the solution using three robots from the ion of the actuator screws the first example is the 3-prps robot as proposed by behi [61] [see fig.3(a)].for each leg the actuated screws lie on theplane defined by the spherical joint center and the revolute joint particular,the actuator screw is perpendicular to the axis of , and the actuator screw is perpendicular to the axis of , these directions being depicted in fig.3(b).the second example is the3-usr robot as proposed by simaan et al.[66][see fig.4(a)].every leg has the actuator screws lying on the plane passing through the spherical joint center and containing the revolute joint actuator screw passes through the spherical joint center and intersects the revolute joint axis rly, the actuator screw passes through the spherical joint center and intersects the revolute joint axis and , these directions being depicted in fig.4(b).the third example is the 3-ppsp robot built by byun and cho [65] [see fig.5(a)].for every leg the actuated screws lie on the plane passing through the spherical joint center and being normal to the prismatic joint actuator screw is perpendicular to the axis of , and the actuator screw is perpendicular to the axis of , these directions being depicted in fig.5(b).fig.3.(a)the 3-prps robot as proposed by behi [61].(b)planes and actuator .4.(a)the 3-usr robot as proposed by simaan and shoham [66].(b)planes and actuator
screws of the 3-usr .5.(a)3-ppsp robot as proposed by byun and cho [65].(b)planes and actuator arity condition
the jacobian(or superbracket)of a robot is decomposed into ordinary bracket monomials using mcmillan’s decomposition, namely(16).as explained in section iii-b, all the robots of the class considered in this paper have two zero-pitch actuator screws passing through the spherical joint of each gically, this description is equivalent to the lines of the 6-3 gsp(or in [53]), which has three pairs of lines, each passing through a double spherical joint on the platform(see fig.6).this means that each pair of lines share one common point(in fig.6 these points are , , and).therefore for the class of robots considered in this paper, we can use the same notation of points as for the 6-3 six lines associated with each robot pass through the pairs of points,and , in the same way as in to the common points of the pairs of lines ,and ,denoted , and respectively, many of the monomials of(16)vanish due to(4).fig.6.6-3 sion
this paper presents singularity analysis for a broad family of parallel are 6-dof three-legged robots which have one spherical joint in each the spherical joints entail the actuator screws to be pure forces acting on their centers, their location along the chain is not family includes 144 mechanisms incorporating diverse types of joints that each has a different joint arrangement along the l proposed and built robots described in the literature appear in this list.a larger number of robots are relevant to this analysis if combinations of different legs are singularity analysis was performed by first finding the lines of action of the actuators using the reciprocity of , with the aid of combinatorial methods and grassmann–cayley operators, the rigidity matrix determinant was obtained in a manipulable coordinate-free form that could be translated later into a simple geometric geometric condition consists of four planes, defined by the actuator lines and the position of the spherical joints, which intersect at least one singularity condition is valid for all the robots in the family under consideration.a comparison of this singularity result with results obtained by other techniques demonstrated that all the previously described singularity conditions are actually special cases of the geometrical condition of four planes intersecting at a point, a condition that was obtained straightforwardly by the method suggested here
两自由度工业机器人 三自由度工业机器人设计篇二
沈阳航空工业学院学士学位论文
机 器 人
工业机器人是在生产环境中以提高生产效率的工具,它能做常规乏味的装配线工作,或能做那些对于工人来说是危险的工作,例如,第一代工业机器人是用来在 核电站中更换核燃料棒,如果人去做这项工作,将会遭受有害的放射线的辐射。工业机器人亦能工作在装配线上将小元件装配到一起,如将电子元件安放在电路印制板,这样,工人就能从这项乏味的常规工作中解放出来。机器人也能按程序要求用来拆除炸弹,辅助残疾人,在社会的很多应用场合下履行职能。
机器人可以认为是将手臂末端的工具、传感器和(或)手爪移到程序指定位置的一种机器。当机器人到达位置后,它将执行某种任务。这些任务可以是焊接、密封、机器装料、拆卸以及装配工作。除了编程以及系统的开停之外,一般来说这些工作可以在无人干预下完成。如下叙述的是机器人系统基本术语:
1.机器人是一个可编程、多功能的机械手,通过给要完成的不同任务编制各种动作,它可以移动零件、材料、工具以及特殊装置。这个基本定义引导出后续段落的其他定义,从而描绘出一个完整的机器人系统。
2.预编程位置点是机器人为完成工作而必须跟踪的轨迹。在某些位
沈阳航空工业学院学士学位论文
置点上机器人将停下来做某些操作,如装配零件、喷涂油漆或焊接。这些预编程点贮存在机器人的贮存器中,并为后续的连续操作所调用,而且这些预编程点想其他程序数据一样,可在日后随工作需要而变化。因而,正是这种编程的特征,一个工业机器 人很像一台计算机,数据可在这里储存、后续调用与编译。
3.机器手是机器人的手臂,它使机器人能弯曲、延伸和旋转,提供这些运动的是机器手的轴,亦是所谓的机器人的自由度。一个机器人能有3~16轴,自由度一词总是与机器人轴数相关。
4.工具和手爪不是机器人自身组成部分,但它们是安装在机器人手臂末端的附件。这些连在机器人手臂末端的附件可使机器人抬起工件、点焊、刷漆、电弧焊、钻孔、打毛刺以及根据机器人的要求去做各种各样的工作。
5.机器人系统还可以控制机器人的工作单元,工作单元是机器人执行任务所处的整体环境,该单元包括控制器、机械手、工作平台、安全保护装置或者传输装置。所有这些为保证机器人完成自己任务而必须的装置都包括在这一工作单元中。另外,来自外设的信号与机器人通讯,通知机器人何时装配工件、取工件或放工件到传输装置上。机器人系统有三个基本部件:机械手、控制器和动力源。
a.机械手
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机械手做机器人系统中粗重工作,它包括两个部分:机构与附件,机械手也用联接附件基座,图21-1表示了一机器人基座与附件之间的联接情况。
机械手基座通常固定在工作区域的地基上,有时基座也可以移动,在这种情况下基座安装在导轨回轨道上,允许机械手从一个位置移到另外一个位置。
正如前面所提到的那样,附件从机器人基座上延伸出来,附件就是机器人的手臂,它可以是直动型,也可以是轴节型手臂,轴节型手臂也是大家所知的关节型手臂。
机械臂使机械手产生各轴的运动。这些轴连在一个安装基座上,然后再连到拖架上,拖架确保机械手停留在某一位置。
在手臂的末端上,连接着手腕(图21-1),手腕由辅助轴和手腕凸缘组成,手腕是让机器人用户在手腕凸缘上安装不同的工具来做不同的工作。
机械手的轴使机械手在某一区域内执行任务,我们将这个区域为机器人的工作单元,该区域的大小与机械手的尺寸相对应,图21-2列举了一个典型装配机器人的工作单元。随着机器人机械结构尺寸的增加,工作单元的范围也必须相应的增加。
机械手的运动有执行元件或驱动系统来控制。执行元件或驱动系统
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允许各轴力经机构转变为机械能,驱动系统与机械传动链相匹配。由链、齿轮和滚珠丝杠组成的机械传动链驱动着机器人的各轴。
b.控制器
机器人控制器是工作单元的核心。控制器储存着预编程序供后续调用、控制外设,及与厂内计算机进行通讯以满足产品更新的需要。
控制器用于控制机械手运动和在工作单元内控制机器人外设。用户可通过手持的示教盒将机械手运动的程序编入控制器。这些信息储存在控制器的储存器中以备后续调用,控制器储存了机器人系统的所有编程数据,它能储存几个不同的程序,并且所有这些程序均能编辑。
控制器要求能够在工作单元内与外设进行通信。例如控制器有一个输入端,它能标识某个机加工操作何时完成。当该加工循环完成后,输入端接通,告诉控制器定位机械手以便能抓取已加工工件,随后,机械手抓取一未加工件,将其放置在机床上。接着,控制器给机床发出开始加工的信号。
控制器可以由根据事件顺序而步进的机械式轮鼓组成,这种类型的控制器可用在非常简单的机械系统中。用于大多数机器人系统中的控制器代表现代电子学的水平,是更复杂的装置,即它们是由微处理器操纵的。这些微处理器可以是8位、16位或32位处理器。它们可以使得控制器在操作过程中显得非常柔性。
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控制器能通过通信线发送电信号,使它能与机械手各轴交流信息,在机器人的机械手和控制器之间的双向交流信息可以保持系统操作和位置经常更新,控制器亦能控制安装在机器人手腕上的任何工具。
控制器也有与厂内各计算机进行通信的任务,这种通信联系使机器人成为计算机辅助制造(cam)系统的一个组成部分。
存储器。给予微处理器的系统运行时要与固态的存储装置相连,这些存储装置可以是磁泡,随机存储器、软盘、磁带等。每种记忆存储装置均能贮存、编辑信息以备后续调用和编辑。
c.动力源
动力源是给机器人和机械手提供动力的单元。传给机器人系统的动力源有两种,一种是用于控制器的交流电,另一种是用于驱动机械手各轴的动力源,例如,如果机器人的机械手是有液压和气压驱动的,控制信号便传送到这些装置中,驱动机器人运动。
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液压与气压系统
仅有以下三种基本方法传递动力:电气,机械和流体。大多数应用系统实际上是将三种方法组合起来而得到最有效的最全面的系统。为了合理地确定采取哪种方法。重要的是了解各种方法的显著特征。例如液压系统在长距离上比机械系统更能经济地传递动力。然而液压系统与电气系统相比,传递动力的距离较短。
液压动力传递系统涉及电动机,调节装置和压力和流量控制,总的来说,该系统包括:
泵:将原动机的能量转换成作用在执行部件上的液压能。阀:控制泵产生流体的运动方向、产生的功率的大小,以及到达执行部件流体的流量。功率大小取决于对流量和压力大小的控制。
执行部件:将液压能转成可用的机械能。
介质即油液:可进行无压缩传递和控制,同时可以润滑部件,使阀体密封和系统冷却。
联接件:联接各个系统部件,为压力流体提供功率传输通路,将液体返回油箱(贮油器)。
油液贮存和调节装置:用来确保提供足够质量和数量并冷却的液体。
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液压系统在工业中应用广泛。例如冲压`钢类工件的磨削几一般加工业、农业、矿业、航天技术、深海勘探、运输、海洋技术,近海天然气和石油勘探等行业,简而言之,在日常生活中有人不从液压技术中得到某种益处。
液压系统成功而又广泛使用的秘密在于它的通用性和易操作性。液压动力传递不会象机械系统那样受到机器几何形状的制约,另外,液压系统不会像电气系统那样受到材料物理性能的制约,它对传递功率几乎没有量的限制。例如,一个电磁体的性能受到钢的磁饱和极限的限制,相反,液压系统的功率仅仅受材料强度的限制。
企业为了提高生产率将越来越依靠自动化,这包括远程和直接控制生产操作、加工过程和材料处理等。液压动力之所以成为自动化的组成部分,是因为它有如下主要的特点:
1.控制方便精确
通过一个简单的操作杆和按扭,液压系统的操作者便能立即起动,停止、加减速和能提供任意功率、位置精度为万分之一英寸的位置控制力。图13-1是一个使飞机驾驶员升起和落下起落架的液压系统,当飞行向某方向移动控制阀,压力油流入液压缸的某一腔从而降下起落架。飞行员向反方向移动控制阀,允许油液进入液压缸的另一腔,便收回起落架。
2.增力 一个液压系统(没有使用笨重的齿轮、滑轮和杠杆)能简单
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有效地将不到一盎司的力放大产生几百吨的输出。
3.恒力或恒扭矩
只有液压系统能提供不随速度变化而变化的恒力或恒扭矩,他可以驱动对象从每小时移动几英寸到每分钟几百英寸,从每小时几转到每分钟几千转。
4.简便、安全、经济
总的来说,液压系统比机械或电气系统使用更少的运动部件,因此,它们运行与维护简便。这使得系统结构紧凑,安全可靠。例如 一种用于车辆上的新型动力转向控制装置一淘汰其他类型的转向动力装置,该转向部件中包含有人力操纵方向控制阀和分配器。因为转向部件是全液压的,没有方向节、轴承、减速齿轮等机械连接,使得系统简单紧凑。
另外,只需要输入很小的扭矩就能产生满足极其恶劣的工作条件所需的控制力,这对于因操作空间限制而需要小方向盘的场合很重要,这也是减轻司机疲劳度所必须的。
液压系统的其他优点包括双向运动、过载保护和无级变速控制,在已有的任何动力、系统中液压系统也具有最大的单位质量功率比。
尽管液压系统具有如此的高性能,但它不是可以解决所有动力传递问题的灵丹妙药。液压系统也有缺点,液压油有污染,并且泄露不可能完全避免,另外如果油液渗漏发生在灼热设备附近,大多数液压油能引起火灾。
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气压系统
气压系统是用压力气体传递和控制动力,正如名称所表明的那样,气压系统通常用空气(不用其他气体)作为流体介质,因为空气是安全、成本低而又随处可得的流体,在系统部件中产生电弧有可能点燃泄露物的场合下(使用空气作为介质)尤其安全。
在气压系统中,压缩机用来压缩并提供所需的空气。压缩机一般有活塞式、叶片式和螺旋式等类型。压缩机基本上是根据理想气体法则,通过减小气体体积来增加气体压力的。气压系统通常考虑采用大的中央空气压缩机作为一个无限量的气源,这类似于电力系统中只要将插头插入插座边可获得电能。用这种方法,压力气体可以总气体源输送到整个工厂的各个角落,压力气体可通过空气滤清器除去污物,这些污染可能会损坏气动组件的精密配合部件如阀和汽缸等,随后输送到各个回路中,接着空气流经减压阀以减小气压值适合某一回路使用。因为空气不是好的润滑油,气压系统需要一个油雾器将细小的油雾注射到经过减压阀减压空气中,这有帮助于减少气动组件精密配合运动件的磨损。
由于来自大气中的空气含不同数量的水分,这些水分是有害的,它可以带走润滑剂引起的过分磨损和腐蚀,因此,在一些使用场合中,要用空气干燥器来除去这些有还的水分。由于气压系统直接向大气排
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气,会产生过大的噪声,因此可在气阀和执行组件排气口安装销声器来降低噪声,以防止操作人员因接触噪声及高速空气粒子有可能引发的伤害。
用气动系统代替液压系统有以下几条理由:液体的惯性远比气体大,因此,在液压系统中,当执行组件加速减速和阀突然开启关闭时,油液的质量更是一个潜在的问题,根据牛顿运动定律,产生加速度运动油液所需的力要比加速同等体积空气所需的力高出许多倍。液体比气体具有更大的粘性,这会因为内摩擦而引起更大的压力和功率损失;另外,由于液压系统使用的液体要与大气隔绝,故它们需要特殊的油箱和无泄露系统设计。气压系统使用可以直接排到周围环境中的空气,一般来说气压系统没有液体系统昂贵。
然而,由于空气的可压缩性,使得气压系统执行组件不可能得到精确的速度控制和位置控制。气压系统由于压缩机局限,其系统压力相当低(低于250psi),而液压力可达1000psi之高,因此液压系统可以是大功率系统,而气动系统仅用于小功率系统,典型例子有冲压、钻孔、夹紧、组装、铆接、材料处理和逻辑控制操作等。
两自由度工业机器人 三自由度工业机器人设计篇三
the development of industrial robots
industrial robot is a robot, it consists of a drive system and detection sensor device composition, it is a kind of humanoid operating automatic control, can repeat programming, can finish all kinds of assignments in three difficulties in authorship space the electromechanical integration automation production equipment, especially suitable for many varieties, become batch flexible to stabilize and improve the product quality, raise efficiency in production, improve working conditions of the rapid renewal plays an extremely important used industrial robots can gradually improve working conditions, stronger and controllable production capacity, speed up product updating and e production efficiency and guarantee the quality of its products, eliminate dull work, save labor, provide a safe working environment, reduces the labor intensity, and reduce labor risk, improve the machine tool, reduce the workload and reduce process production time and inventory, enhance the competitiveness of technology advances, the development of industrial robot, the process can be divided into three generations--generation, for demonstration reproduce, and it mainly consists of robot hand controller and demonstration teaching machines composed, can press advance box to record information guide action, the current industry repeated reappearance application of execution second to feel robot, such as powerful sleep touch and vision, it has for some outside information feedback adjustment ability, currently has entered the application generation of intelligent robot it has sense and understanding ability, in the external environment for the working environment changed circumstances, can also successfully complete the task, it is still in the experimental research united states is the birthplace of the robot, as early as in 1961, america's consolidedcontrolcorp and amf companies developed the first practical demonstration emersion 40 years of development, the united states in the world of robotics has been in the lead its technology comprehensive, advanced, adaptability is imported from america in 1967, the first robot in 1976 later, with the rapid development of the microelectronics and the market demand has increased dramatically, japan was labor significant deficiencies in
enterprise, industrial robots by “savior”'s welcome, make its japanese industrial robots get fast development, the number of now whether robots or robot densities are top of the world, known as the “robot kingdom,” robot introduced from germany time than britain and sweden about late 1956, but the labour shortages caused by war, national technical level is higher social environment, but for the development and application of industrial robot provides favorable addition, in germany, for some dangerous prescribed, poisonous or harmful jobs, robot instead of ordinary people to the is the use of robots exploit a wide range of markets, and promote the development of the industrial robot present, the german industrial robots total of the world, which only behind to french government has been more important robot technology, and through a series of research program, support established a complete science and technology system, make the development of the french robot government organization project, pay special attention to the robot research based technique, the focus is on the application research on in by industry support the development application and development of work, both supplement each other, make robots in france enterprises develop rapidly and popularize and make france in the international industrial machine with indispensable if h jamie since the late 1970s, promote and implement a department measures listed support the development of policies and make robots british industrial robots than today's robot powers started to early, and once in japan has made the early r, at this time the government for industrial robots implemented the constraining mistake in britain dust, the robot industry in western europe was almost in the bottom of recent years, italy, sweden, spain, finland, denmark and other countries because of its own domestic robots market in great demand, development at a very fast present, the international on industrial robot company mainly divided into japanese and european anchuan of japanese are mainly the ethical products, the otc, panasonic, fanluc, not two more, products of the company kawasaki the main asiatic kuka, german cloos, sweden's abb, italy co work pelatiah u and austria gm rial robot in china started in early 1970s, after 30 years development, roughly experienced three stages: in the 1970s and 1980s budding transplanter and the application of the 1990s initialization the 20th century 70's world technology rapid development, the application of industrial robots in world created a climax, in this context, our country in 1972 start developing their industrial after the 1980s, with the further reform and opening, in high technology waves pound, our research and development of robot technology from the government's attention and support, “during the seventh state funds, thanked the parts were set robot and research, completed demonstration emersion type industrial robot complete technology development, developed spray paint, welding, arc welding and handling robot., the national high technology research and development program begin to carry out, after several years research and made a large number of scientific sfully developed a batch of special 9o 2o century since the early, china's national economy achieve two fundamental period of transformation into a a new round of economic restructuring and technological progress, china's industrial robots upsurge in practice and have made strides, and have developed spot welding, welding, assembling, paint, cutting, handling, palletizing etc various uses of industrial robot, and implement a batch of robot application engineering, formed a batch of industrial robots for our country industrialization base, the industrial robot soar laid a compared with the developed countries, china also has the very big disparity of industrial with the development of industrial robot depth and the breadth and raise the level of robot, industrial robots are has been applied in many the traditional automobile manufacturing sector to the manufacturing as mining robots, building robots and hydropower system used for maintenance robots, defense of military, medicine and health, food processing and life service areas such as the application of industrial robots will be more and manufacturing of automobiles is a technology and capital intensive industry, is also the most widely used of industrial robots, accounting for almost to the industry for more than half of the industrial china, the industrial robot first is also used in automobile and engineering machinery car production of industrial robot is a major in the equipment, the brake parts and whole production of arc welding, spot welding, painting, handling, glue, stamping process used in large country is forecast to rise period, entered the automobile ownership in the next few years, car will still growing at around 15 percent the next few years the industrial robot demand will show high growth trend, about 50% in growth, industrial robots in our automobile industry application will get a rapid rial robot in addition to the wide application of in the automotive industry in electronic, food processing, nonmetal processing, daily consumer goods and wood furniture processing industries for
industrial robots demand is growing asia, 2005 72,600 sets, installation industrial robots, compared with 2004 grew by 40%, and application in electronic industry accounted for about 31%.in europe, according to statistics, since 2004 and 2005 in l: ti industry robot in the food processing industry increased 17% the application of left and right sides, in the application of nonmetal processing industry increased 20%, and daily necessities in consumption industries increased by 32% in wood furniture processing industry, up 18% or rial robot in oil has a wide application in, such as sea oil drilling, oil platforms, pipeline detection, refinery, large oil tank and tank welding etc all can use robots to the next few years, sensing technology, laser technology, engineering network technology will be widely used in industrial robots work areas, these technologies can cause the industrial robot application more efficient, high quality, lower is predicted that future robots will in medical and health care, biological technology and industry, education, relief, ocean exploitation, machine maintenance, transportation and agriculture and aquatic products applied china, the industrial robot market share are mostly foreign industrial robots enterprise the gunman in the international, domestic industrial robots enterprise facing great pressure of china is from a ”manufacturing power“ to ”manufacturing power forward,“ chinese manufacturing industry faces and the international community, participate in the international division of labor in the great challenge of industrial automation increase immediate, government must can increase the funds for robots and policy support, will give the industry of industrial robots development into new independent brand ”devil robot" moshi special technology company dedicated to providing solutions to the mainboard and robot, is willing with all my colleagues a build domestic industrial robot happy tomorrow!
references electronic measurement and intrumenttations,cambridge university press,1996
工业机器人的发展
工业机器人是机器人的一种,它由操作机.控制器.伺服驱动系统和检测传感器装置构成,是一种仿人操作自动控制,可重复编程,能在三难空间完成各种作业的机电一体化的自动化生产设备,特别适合于多品种,变批量柔性生产。它对稳定和提高产品质量,提高生产效率,改善劳动条件的快速更新换代起着十分重要作用。
广泛的应用工业机器人,可以逐步改善劳动条件,更强与可控的生产能力,加快产品更新换代。提高生产效率和保证产品质量,消除枯燥无味的工作,节约劳动力,提供更安全的工作环境,降低工人的劳动强度,减少劳动风险,提高机床,减少工艺过程中的工作量及降低停产时间和库存,提高企业竞争力。
随着科技的不断进步,工业机器人的发展过程可分为三代,第—代,为示教再现型机器人,它主要由机器手控制器和示教盒组成,可按预先引导动作记录下信息重复再现执行,当前工业中应用最多。第二代为感觉型机器人,如有力觉触觉和视觉等,它具有对某些外界信息进行反馈调整的能力,目前已进入应用阶段。第三代为智能型机器人它具有感知和理解外部环境的能力,在工作环境改变的情况下,也能够成功地完成任务,它尚处于实验研究阶段。
美国是机器人的诞生地,早在1961年,美国的consolidedcontrolcorp和amf公司联合研制了第一台实用的示教再现机器人。经过40多年的发展,美国的机器人技术在国际上仍一直处于领先地位。其技术全面、先进,适应性也很强。
日本在1967年从美国引进第一台机器人,1976年以后,随着微电子的快速发展和市场需求急剧增加,日本当时劳动力显著不足,工业机器人在企业里受到了“救世主”般的欢迎,使其日本工业机器人得到快速发展,现在无论机器人的数量还是机器人的密度都位居世界第一,素有“机器人王国”之称。德国引进机器人的时间比英国和瑞典大约晚了五六年,但战争所导致的劳动力短缺,国民的技术水平较高等社会环境,却为工业机器人的发展、应用提供了有利条件。此外,在德国规定,对于一些危险、有毒、有害的工作岗位,必须以机器人来代替普通人的劳动。这为机器人的应用开拓了广泛的市场,并推动了工业机器人技术的发展。目前,德国工业机器人的总数占世界第二位,仅次于日本。
法国政府一直比较重视机器人技术,通过大力支持一系列研究计划,建立了一个完整的科学技术体系,使法国机器人的发展比较顺利。在政府组织的项目中,特别注重机器人基础技术方面的研究,把重点放在开展机器人的应用研究上。而由工业界支持开展应用和开发方面的工作,两者相辅相成,使机器人在法国企业界得以迅速发展和普及,从而使法国在国际工业机器人界拥有不可或缺的一席之地。
英国纪70年代末开始,推行并实施了一系措施列支持机器人发展的政策,使英国工业机器人起步比当今的机器人大国日本还要早,并曾经取得了早期的辉煌。然而,这时候政府对工业机器人实行了限制发展的错误。这个错误导致英国的机器人工业一蹶不振,在西欧几乎处于末位。近些年,意大利、瑞典、西班牙、芬兰、丹麦等国家由于自身国内机器人市场的大量需求,发展速度非常迅速。目前,国际上的工业机器人公司主要分为日系和欧系。日系中主要有安川、otc、松下、fanluc、不二越、川崎等公司的产品。欧系中主要有德国的kuka、cloos、瑞典的abb、意大利的co毗u及奥地利的工gm公司。
我国工业机器人起步于20世纪70年代初期,经过30多年发展,大致经历
了3个阶段:70年代萌芽期,80年代的开发期和90年代的应用化期。随着20世纪70年代世界科技快速发展,工业机器人的应用在世界掀起了一个高潮,在这种背景下,我国于1972年开始研制自己的工业机器人。进入20世纪80年代后,随着改革开放的不断深入,在高技术浪潮的冲击下,我国机器人技术的开发与研究得到了政府的重视与支持,“七五”期间,国家投入资金,对工定机器人及零部件进行攻关,完成了示教再现式工业机器人成套技术的开发,研制出了喷漆,点焊,弧焊和搬运机器人。,国家高技术研究发展计划开始实施,经过几年研究,取得了一大批科研成果。成功地研制出了一批特种机器人。
从2o世纪9o年代初期起,我国的国民经济进入实现两个根本转变期,掀起了新一轮的经济体制改革和技术进步热潮,我国的工业机器人又在实践中迈进了一大步,先后研制了点焊,弧焊,装配,喷漆,切割,搬运,码垛等各种用途的工业机器人,并实施了一批机器人应用工程,形成了一批工业机器人产业化基地,为我国机器人产业的腾飞奠定了基础。但是与发达国家相比,我国工业机器人还有很大差距。
随着工业机器人发展的深度和广度以及机器人智能水平的提高,工业机器人已在众多领域得到了应用。从传统的汽车制造领域向非制造领域延伸。如采矿机器人、建筑业机器人以及水电系统用于维护维修的机器人等。在国防军事、医疗卫生、食品加工、生活服务等领域工业机器人的应用也越来越多。汽车制造是一个技术和资金高度密集的产业,也是工业机器人应用最广泛的行业,几乎占到整个工业机器人的一半以上。在我国,工业机器人最初也是应用于汽车和工程机械行业中。在汽车生产中工业机器人是一种主要的制动化设备,在整车及零部件生产的弧焊、点焊、喷涂、搬运、涂胶、冲压等工艺中大量使用。据预测我国正在进入汽车拥有率上升时期,在未来几年里,汽车仍将每年15%左右的速度增长。所以未来几年工业机器人的需求将会呈现出高速增长趋势,年增幅达到50%左右,工业机器人在我国汽车行业的应用将得到快速发展。
工业机器人除了在汽车行业的广泛应用,在电子,食品加工,非金属加工,日用消费品和木材家具加工等行业对工业机器人的需求也快速增长。在亚洲,2005年安装工业机器人72,600台,与2004年相比,增长了40%,而应用在电子行业的就占了31%左右。在欧洲地区,据统计2005年与2004年相l:ti业机器人在食品加工行业的应用增长了17%左右,在非金属加工行业的应用增长了20%左右,在日用品消费行业增长了32%,在木材家具加工行业增长了18%左右。工业机器人在石油方面也有广泛的应用,如海上石油钻井、采油平台、管道的检测、炼油厂、大型油罐和储罐的焊接等均可使用机器人来完成。在未来几年,传感技术,激光技术,工程网络技术将会被广泛应用在工业机器人工作领域,这些技术会使工业机器人的应用更为高效,高质,运行成本低。据预测,今后机器人将在医疗、保健、生物技术和产业、教育、救灾、海洋开发、机器维修、交通运输和农业水产等领域得到应用。
在我国,工业机器人市场份额大部分被国外工业机器人企业占据着。在国际强手面前,国内的工业机器人企业面临着相当大的竞争压力。如今我国正从一个“制造大国”向“制造强国”迈进,中国制造业面临着与国际接轨、参与国际分工的巨大挑战,对我国工业自动化的提高迫在眉睫,政府务必会加大对机器人的资金投入和政策支持,将会给工业机器人产业发展注入新的动力。拥有自主品牌“妖怪机器人”的莫士特科技公司致力于提供机器人主板和解决方案,愿与各界同仁一道打造国产工业机器人的美好明天!
两自由度工业机器人 三自由度工业机器人设计篇四
外 文 翻 译
introduction to robotics
mechanics and control
机器人学入门
力学与控制
系
别: 机械与汽车工程系 专学业生
名姓
称: 机械设计制造及其自动化 名: 郭仕杰
学
号:
06101315 指导教师姓名、职称: 贺秋伟 副教授
完成日期 2014 年2 月28日 introduction to robotics
mechanics and control
abstract this book introduces the science and engineering of mechanical branch of the robot has been in several classical field main related fields such as mechanics, control theory, computer this book, chapter 1 through 8 topics ranging from mechanical engineering and mathematics, chapter 9 through 11 cover control theory of material, and twelfth and 13 may be classified as computer science addition, this book emphasizes the computational aspects of the problem;for example, each chapter it mainly mechanical has a brief section book is used to teach the class notes introduction to robotics, stanford university in the fall of 1983 to first and second versions have been through 2002 in use from 1986 the third version can also benefit from the revised and improved due to feedback from many to all those who modified the author's book is suitable for advanced undergraduates the first grade students have contributed to the dynamics and linear algebra course in advanced language program in a basic course of addition, it is helpful, but not absolutely necessary, let the students finish the course control purpose of this book is a simple introduction to the material, intuitive ically, does not need the audience mechanical engineer strict, although much of the material is from the the stanford university, many electrical engineers, computer scientists, mathematicians find this book very we only on the important part to main content
1、background
the historical characteristics of industrial automation is popular during the period of rapid as a cause or an effect of automation technology, period of this change is closely linked to the world of industrial robots, can be identified in a unique device 1960's, with the development of computer aided design(cad)system and computer aided manufacturing(cam)system, the latest trends, automated manufacturing technology is the leading industrial automation through another transition, its scope is still the northern america, machinery and equipment used in early 80's of the 20th century, the late 80's of the 20th century a short then, the market more and more(figure 1.1), although it is affected by economic fluctuations, all the 1.2 shows the robots were installed in a large number of annual world industrial y, the number of japan's report is different from other areas: they count the number of machine of robot in other parts of the world are not considered robot(instead, they would simply be considered “factory machines”).therefore, the reported figures for the japanese of the main reason for the growth in the use of industrial robots is that they are falling .1.3 shows that, in the last century 90's ten years, robot prices dropped although human labor the same time, the robot is not only cheaper, they become more effective and faster, more accurate, more we factor these quality adjusted to the number, the use of robots to decrease the cost of even than their price tag cost-effective in the robot they become, as human labor to become more expensive, more and more industrial work become robot automation is the most important trend to promote the industrial robot market second trend is, in addition to the economic, as robots become more can become more tasks they can do, may have on human workers engaged in dangerous or rial robots perform gradually get more complex, but it is still, in 2000, about 78% installation welding or material handling robot in usa robot.a more challenging field, industrial robots, accounted for 10% book focuses on the dynamics and control of the most important forms of industrial robot, is the industrial robot is sometimes ent, as shown in figure 1.4 is always included, and cnc milling machine(nc)is usually difference lies in the programmable complex place if a mechanical device can be programmed to perform a variety of applications, it may be an industrial is the part of a limited class of tasks are considered fixed the purpose of this difference, do not need to be discussed;the basic properties of most materials suitable for various programmable general, the mechanical and control research of the mechanical hand is not a new science, but a collection of the theme from the “classic” ical engineering helps to machine learning methods for static and dynamic mathematical description of movement of the tool manipulator space supply and other e design evaluation tool to realize the motion and force the desired algorithm control ical engineering technology applied in the design of electrical engineering technology for sensor applied in design and industrial robot interface sensor, are programmed to perform the required task of basic computer science and the s:
figure 1.1: shipments of industrial robots in north america in millions of us
dollars
figure 1.2: yearly installations of multipurpose industrial robots for 1995-2000 and
forecasts for 2001-2004
figure 1.3: robot prices compared with human labor costs in the 1990s
figure 1.4:the adept 6 manipulator has six rotational joints and is popular in many sy of adept technology, inc.2、control of mechanical arm in the study of robots, 3d spatial position we constantly to the object of objects are all manipulator links, parts and tools, it deals, and other objects in the robot's a coarse and important level, these objects are described by two attributes: the position and course, a direct interest in the topic is the attitude in which we represent these quantities and manipulate their order to describe the human body position in space and direction, we will always highly coordinate system, or frame, rigid we continue to describe the position and orientation of the reference frame of the coordinate framework can be used as a reference system in the expression of a body position and direction, so we often think of conversion or transformation of the body of these properties from one frame to another 2 chapter discusses the convention methods of dealing with job descriptions discussed method of treating and post convention described positioning and manipulation of coordinate system the quantity and mathematics developed skills relevant to the position and rotation of the description and is very useful in the field of rigid tics is the science of sports, the movement does not consider the force which resulted in the scientific research of kinematics, a position, velocity, acceleration, and the location variable high order derivative(with respect to time of all or any of the other variables(s)).therefore, the kinematics of manipulator is refers to the geometric and temporal characteristics of all manipulator comprises nearly rigid connection, which is the relative movement of the joint connection of adjacent nodes are usually instrument position sensor, so that adjacent link is a relative position the case of rotating or rotary joint, the displacement is called the joint robots including sliding(or prism)connection, in which the connection between the relative displacement is a translation, sometimes called the joint manipulator has a number of independent position variables are specified as the mechanism to all parts of is a very general term, any example, a four connecting rod mechanism has only one degree of freedom(even with three members of the movement).in the case of the typical industrial robots, because the robots is usually an open kinematic chain, because each joint position usually define a variable, the node is equal to the number of degrees of free end of the link chain consisting of the manipulator end ing to the application of robot, the end effector can be a starting point, the torch, electromagnet, or other usually by mechanical hand position description framework description tool, which is connected to the end effector, relative to the base, the base of the mobile the study of mechanical operation of a very basic problem is the is to compute the position of mechanical static geometric problems in hand terminal ically, given a set of joint angles, the forward kinematics problem is to compute the position and orientation relative to the base of the tool mes, we think this is a change from the joint space is described as a manipulator position that cartesian space description.“this problem will be discussed in the 3 the 4 chapter, we will consider the inverse kinematics problems are as follows: the end effector position and direction of the manipulator, computing all possible joint angle, can be used to achieve the position and direction of a given.(see figure 1.7.)this is a practical problem of manipulator is is quite a complex geometry problem, the conventional solution in tens of thousands of humans and other biological systems time every a case like a robot simulation system, we need to create computer control algorithm can make the some ways, the solution to this problem is the most important element in the operating is quite a complex geometry problem, the conventional solution in tens of thousands of humans and other biological systems time every a case like a robot simulation system, we need to create computer control algorithm can make the some ways, the solution to this problem is the most important element in the operating can use this problem as a mapping on 3d descartes ”position“ space ”position“ in the robot joint need will occur when the 3d spatial objects outside the specified of this kind of algorithm some early robot, they just transfer(sometimes by hand)required for the position, and then be recorded as a common set of values(i.e., as a position in joint space for later playback).obviously, if the playback position and motion pattern recording and joint of the purely robot in cartesian space, no algorithm for the joint space is r, the industrial robot is rare, the lack of basic inverse kinematics inverse kinematics problem is not a simple forward kinematics of equation of motion is nonlinear, their solution is not always easy(or even possible in a closed form).at the same time, the existing problems of solutions and multiple solutions study of these problems provides an appreciation of what the human mind nervous system is achieved when we, there seems to be no conscious thought, object movement and our arms and hands lator is a solution of the presence or absence of a given definition of work area.a solution for the lack of means of mechanical hands can not reach the desired position and orientation, because it is in the manipulator working addition to static positioning problem, we can analyze the robot y, the analysis in the actuator velocity, it is convenient to define a matrix called the jacobi matrix of the speed of jacobi matrix specified in descartes from the velocity mapping space and joint space.(see figure 1.8.)this mapping configuration of the manipulator changes the natural some point, called a singularity, this mapping is not to make the phenomenon are important to the understanding of the mechanical hand designers and s:
figure 1.5: coordinate systems or ”frames“ are attached to the manipulator and to
objects in the 1.6: kinematic equations describe the tool frame relative to the base frame
as a function of the joint 1.7: for a given position and orientation of the tool frame, values for the joint variables can be calculated via the inverse 1.8: the geometrical relationship between joint rates and velocity of the end-effector can be described in a matrix called the jacobian.3、symbol symbol is always the problems in science and this book, we use the following convention: first: usually, uppercase variables vector or lowercase :tail buoy use(such as the widely accepted)indicating inverse or transposed :tail buoy not subject to strict conventions, but may be that the vector components(for example, x, y, z)or can be used to describe the pbo / p in a position of the :we will use a lot of trigonometric function, we as a cosine symbol angle e1 can adopt the following methods: because the e1 = ce1 = the vector sign note general: many mechanics textbook treatment number of vector at a very abstract level and often used vector is defined relative to expression in different coordinate most obvious example is, in addition to vector is relative to a given or known a different frame of is usually very convenient, resulting in compact structure, elegant example, consider the angular velocity, connected in series with the last body ° w4 'four rigid body(such as the manipulator links)relative to the fixed seat to the angular velocity vector addition, angular velocity equation at last link we can write a very simple vector:
however, unless the information is relative to a common coordinate system, they cannot be concluded, therefore, although elegant, equation(1.1) of the ”work“.a case study of the manipulator, such statements,(1.1)work coordinate system hidden bookkeeping, which is often we need to ore, in this book, we put the symbol reference frame vectors, we don't and carrier, unless they are in the same coordinate this way, we derive expressions for computing numerical solution, ”bookkeeping" problem can be directly applied to the y the robot is a typical electromechanical integration device, it uses the latest research results of machinery and precision machinery, microelectronics and computer, automation control and drive, sensor and information processing and artificial intelligence and other disciplines, with the development of economy and all walks of life to the automation degree requirements increase, the robot technology has been developing rapidly, the emergence of a variety of robotic utility of robot products, not only can solve many practical problems difficult to solve by manpower, and the promotion of industrial automation present, the research and development of robot relates to many aspects of the technology, the complexity of system structure, development and development cost is generally high, limiting the application of the technology, to some extent, therefore, the development of economic, practical, high reliability of robot system with a wide range of social significance and economic on the design of mechanical structure and drive system, the kinematics and dynamics of the cleaning robot is tics analysis is the basis of path planning and trajectory control of the manipulator, the kinematics analysis, inverse problem can complete the operation of space position and velocity mapping to drive space, using the homogeneous coordinate transformation method has been the end of manipulator position and arthrosis transform relations between the angle, geometric analysis method to solve the inverse kinematics problem of manipulator, provides a theoretical basis for control system robot dynamics is to study the relationship between the motion and force of science, the purpose of the study is to meet the need of real-time control, this paper use straightaway language introduced the related mechanical industrial robots and control knowledge for us, pointing the way for our future research is a very complicated learning, in order to go into it, you need to constantly learn, the road ahead is long, i shall search.机器人学入门
力学与控制
摘要
本书介绍了科学与工程机械操纵。这一分支学科的机器人已经在几个经典的领域为基础的。主要的相关的领域是力学,控制理论,计算机科学。在这本书中,第1章通过8个主题涵盖机械工程和数学,第9章通过11个盖控制理论材料,第12和13章可能被归类为计算机科学材料。此外,这本书强调在计算方面的问题;例如,每章这方面主要以力学有一个简短的章节计算考虑。这本书是从课堂笔记用来教机器人学导论,斯坦福大学在1983的秋天到1985。第一和第二版本已经通过2002在从1986个机构使用。第三版也可以从中受益的使用和采用的修正和改进由于许多来源的反馈。感谢所有那些谁修正了作者的朋友们。这本书是适合高年级本科生一年级的课程。如果学生已经在静力学的一门基础课程有助于动力学和线性代数课程可以在高级语言程序。此外,它是有帮助的,但不是绝对必要的,让学生完成入门课程控制理论。本书的目的是在一个简单的介绍材料,直观的方式。具体地说,观众不需要严格的机械工程师,虽然大部分材料是从那场。在斯坦福大学,许多电气工程师,计算机科学家,数学家发现这本书很易读。在这里我们仅对其中重要部分做出摘录。
主要内容
1、背景
工业自动化的历史特点是快速变化的时期流行的方法。无论是作为一个原因或一个效果,这种变化的时期自动化技术是紧密联系在一起的世界经济。利用工业机器人,成为可识别在1960年代的一个独特的装置,随着计算机辅助设计(cad)系统和计算机辅助制造(cam)系统的特点,最新的趋势,制造业的自动化过程。这些技术是领先的工业自动化 通过另一个过渡,其范围仍然是未知的。在美国北部,在早期有机器设备多采用世纪80年代,其次是上世纪80年代后期一个简短的拉。自那时起,市场越来越多的(图1.1),虽然它是受经济波动,是所有市场。图1.2显示的机器人被安装在大数每年世界各国的工业区。值得注意的是,日本的报告数量有所不同从其他地区一样:他们算一些机器的机器人在世界的其他地方都没有考虑机器人(而不是,他们会简单地认为是“工厂的机器”)。因此,该报告的数字为日本有些夸大。
在工业机器人的使用增长的一个主要原因是他们正在下降成本。图1.3表明,在上世纪90年代的十年中,机器人的价格下降了虽然人类的劳动成本增加。同时,机器人不只是越来越便宜,他们变得更有效更快,更准确,更灵活的。如果我们的因素这些质量调整成数,使用机器人的成本下降甚至比他们的价格标签更快。在他们的工作机器人变得更具成本效益的,作为人类劳动继续变得更加昂贵,越来越多的工业工作成为机器人自动化的候选人。这是最重要的趋势推动了工业机器人的市场增长。第二个趋势是,除了经济,随着机器人变得更能成为他们能够做的更多以上的任务,可能对人类工人从事危险的或不可能的。工业机器人执行逐步得到更多的应用复杂的,但它仍然是,在2000年,大约78%安装在美国进行焊接或材料搬运机器人的机器人。
一个更具挑战性的领域,工业机器人,占10%装置。这本书着重于力学和最重要的形式控制的工业机器人,机械手。到底什么是工业机器人是有时辩论。设备,如图1.4所示是总是包括在内,而数控(nc)铣床通常不。区别在于的可编程的复杂的地方如果一个设备机械设备可以被编程为执行各种应用程序,它可能是一个工业机器人。这是最机部分有限的一类的任务被认为是固定的自动化。为目的本文的区别,不需要讨论;大多数材料的基本性质适用于各种可编程机。
总的来说,其力学和控制机械手的研究不是一个新的科学,而只是一个收集的主题从“经典”的领域。机械工程有助于机器学习方法静态和动态的情况下。数学描述空间供应工具机械手的运动和其他属性。控制理论提供了工具以实现所期望的运动和力的应用评价算法设计。电气工程技术施加在传感器的设计电气工程技术施加在传感器的设计和工业机器人接口,与计算机科学的基础这些设备进行编程以执行所需任务。
附图:
图1.1在数以百万计的人在美国北部的工业机器人的出货量美元
图1.2 年安装的多用途的工业机器人1995-2000年和2001年至2004年预测
图1.3 机器人的价格与上世纪90年代的人类劳动成本的比较
图1.4 娴熟的6臂有六个转动关节(流行于众多制造行业)
2、力学和机械臂的控制
机器人的研究中,我们不断的关注对象的位置三维空间。这些对象是机械手的链接,零件和工具,它的交易,并在机器人的环境的其他对象。在一个粗而重要的水平,这些对象是由两个属性描述:位置和方向。当然,一个直接感兴趣的话题是态度在我们所代表的这些量和操纵他们的数学。
为了描述人体在空间中的位置和方向,我们将始终高度坐标系统,或框架,严格的对 象。然后我们继续相对于一些参考描述该帧的位置和方向坐标系统。任何框架可以作为一个参考系统内的表达一个身体的位置和方向,所以我们经常认为转化或改变身体的这些属性从一帧到另一个的描述。2章讨论了公约的方法处理与职位描述讨论了公约的方法处理与职位描述定位和操纵这些量与数学不同的坐标系统。发展良好的技能有关的位置和旋转的描述甚至在刚体机器人领域是非常有用的。
运动学是科学的运动,对运动不考虑力这导致它。在运动学的科学研究,一个位置,速度,加速度,和所有的高阶导数的位置变量(相对于时间或任何其他变量(s))。因此,机械手的运动学研究是指所有的运动的几何和时间特性。机械手包括近刚性连接,这是由关节连接允许相邻链接的相对运动。这些节点通常仪表有位置传感器,使邻近的链接是相对位置测量。在旋转或旋转接头的情况下,这些位移被称为关节角度。一些机器人包含滑动(或棱镜)连接,其中之间的联系相对位移是一个翻译,有时也被称为联合偏移量。机械手具有数独立的位置的变量会被指定为定位该机制的所有部分。这是一个总称,任何机制。为例如,一个四连杆机构只有一个自由度(即使有三运动的成员)。在典型的工业机器人的情况下,因为机器人通常是一个开放的运动链,因为每个关节的位置通常定义一个变量,节点的数目等于自由度。
在链接组成的机械手的末端执行器的自由端链。根据机器人的应用,末端执行器可以是一个抓手,焊枪,电磁铁,或其他装置。我们一般通过描述工具的框架描述的机械手的位置,这是连接到端部执行器,相对于底座,所对移动机械手的基础。在机械操作的研究一个非常基本的问题就是了运动学。这是计算的位置的静态几何问题机械手的末端定位。具体而言,给定一组关节角,正向运动学问题是计算位置和方向工具架相对于底座。有时,我们认为这是改变从关节空间描述为一个机械手位置的表示笛卡尔空间的描述。“这个问题将在3章探讨。在4章中,我们将考虑的逆运动学问题。这个问题提出了如下:给出了末端执行器的位置和方向机械手,计算所有可能的关节角度,可以用来实现这个给定的位置和方向。(见图1.7。)这是一个根本性的问题机械手的实际应用。这是一个相当复杂的几何问题,常规的解决在人类和其他生物系统时间每天成千上万。在一个案例像一个机器人仿真系统,我们需要创建的控制算法计算机可以使这个计算。在某些方面,这个问题的解决方案是在操作系统中最重要的元素。
这是一个相当复杂的几何问题,常规的解决在人类和其他生物系统时间每天成千上万。在一个案例像一个机器人仿真系统,我们需要创建的控制算法计算机可以使这个计算。在某些方面,这个问题的解决方案是在操作系统中最重要的元素。
我们可以把这个问题作为一个映射在三维笛卡尔的“位置”空间的“位置”在机器人的关节内的空间。这需要自然会出现每当目标外部三维空间指定的坐标。一些早期的机器人缺乏这种算法,他们只是转移(有时用手)所需的的位置,然后被记录为一组共同的值(即,作为一个位置关节空间)用于以后回放。显然,如果机器人用纯粹的模式记录和关节的位置和运动的播放,没有算法有关的关节空间的笛卡尔空间是必要的。然而,是罕见的工业机器人,缺乏基本的逆运动学算法。逆运动学问题不是简单的正向运动学一个。由 于运动方程是非线性的,他们的解决方案并不总是容易(甚至可能在一个封闭的形式)。同时,对存在的问题解和多解的出现。这些问题的研究提供了一个欣赏什么人的心灵神经系统是实现当我们,似乎没有有意识的思考,移动和我们的双臂和双手操作的对象。一个解的存在或不存在的定义工作区一个给定的机械手。一个解决方案的缺乏意味着机械手不能达到所需的位置和方向,因为它在机械手的外工作区。
除了处理静态定位问题,我们不妨分析机器人的运动。通常,在执行机构的速度分析,它是方便的定义一个矩阵的数量称为机械手的雅可比矩阵.指定的速度雅可比矩阵在笛卡尔从关节空间的速度映射空间。(见图1.8。)这种映射配置的自然变化机械手的变化。在某些点,称为奇点,这映射是不使转化。这一现象的理解是设计师和用户的重要机械手。
附图:
图1.5 坐标系统或“帧”连接到机械手环境中的物体
图1.6运动学方程描述刀具架相对于底座作为一个联合变量的函数
图1.7 对于一个给定的位置和方向的工具框架,值为关节变量可以通过逆运动学计算
图1.8 联合率和速度之间几何关系端部执行器可以在一个矩阵描述了所谓的雅可比矩阵
3、标识符号
符号一直是科学和工程问题。在这本书中,我们使用以下公约: 第一、通常,大写变量表示的向量或矩阵。小写的变量的标量。第二、尾标使用(如被广泛接受的)指示逆或转置矩阵。
第三、尾标不受严格的公约,但可能表明向量的组件(例如,x,y,z)或可用于述在pbo / p一个螺栓的位置。
第四、我们将使用许多三角函数,我们为一个余弦符号角e1可以采用下列方式:因
为e1 = ce1 = c1。
在一般的矢量符号注:许多力学教材处理矢量在一个非常抽象的层次上的数量和经常使用向量定义相对于在表达不同的坐标系统。最明显的例子是,除了向量是给定的或已知的相对于不同的参考系。这是通常很方便,导致结构紧凑,有优雅的公式。为例如,考虑角速度,在串联连接的最后一次身体°w4 '四刚体(如机械手的链接)相对的固定座链。由于角速度矢量相加,我们可以写一个非常简单的向量的最后环节的角速度方程:
然而,除非这些量是相对于一个共同的坐标表示系统,他们不能总结,所以,虽然优雅,方程(1.1)隐藏大部分的“工作”的计算。为研究个案机械手,这样的陈述,(1.1)隐藏簿记的工作坐标系统,这往往是我们需要实践的想法。因此,在这本书中,我们把符号参考框架向量,我们不要和载体,除非他们在同一坐标系统。在这种方式中,我们推导出的表达式,解决“记账”问题可直接应用于实际的数值计算。
总结
机器人是典型的机电一体化装置,它综合运用了机械与精密机械、微电子与计算机、自动控制与驱动、传感器与信息处理以及人工智能等多学科的最新研究成果,随着经济的发展和各行各业对自动化程度要求的提高,机器人技术得到了迅速发展,出现了各种各样的机器人产品。机器人产品的实用化,既解决了许多单靠人力难以解决的实际问题,又促进了工业自动化的进程。目前,由于机器人的研制和开发涉及多方面的技术,系统结构复杂,开发和研制的成本普遍较高,在某种程度上限制了该项技术的广泛应用,因此,研制经济型、实用化、高可靠性机器人系统具有广泛的社会现实意义和经济价值。在完成机械结构和驱动系统设计的基础上,对物料抓取机械手运动学和动力学进行了分析。运动学分析是路径规划和轨迹控制的基础,对操作臂进行了运动学正、逆问题的分析可以完成操作空间位置和速度向驱动空间的映射,采用齐次坐标变换法得到了操作臂末端位置和姿态随关节夹角之间的变换关系,采用几何法分析了操作臂的逆向运动学方程求解问题,对控制系统设计提供了理论依据。机器人动力学是研究物体的运动和作用力之间的关系的科学,研究的目的是为了满足是实时性控制的需要,本文用通俗易懂的语言为我们介绍了工业机器人的相关力学与控制的知识,为我们以后的研究方向指明了道路。机器人的研究是一门非常复杂的学问,为了深入去探究它的方方面面,就需要不断的去学习,正所谓路漫漫其修远兮,吾将上下而求索。
两自由度工业机器人 三自由度工业机器人设计篇五
动态优化的一种新型高速,高精度的三自由度机械手
①
彭兰(兰朋)②,鲁南立,孙立宁,丁倾永
(机械电子工程学院,哈尔滨理工学院,哈尔滨 150001,中国)(robotics institute。harbin institute of technology,harbin 150001,p。r。china)
摘要
介绍了一种动态优化三自由度高速、高精度相结合,直接驱动臂平面并联机构和线性驱动器,它可以提高其刚度进行了动力学分析软件adams仿真模拟环境中,进行仿真模拟实验.设计调查是由参数分析工具完成处理的,分析了设计变量的近似的敏感性,包括影响参数的每道光束截面和相对位置的线性驱动器上的性能.在适当的方式下,模型可以获得一个轻量级动态优化和小变形的参数。一个平面并联机构不同截面是用来改进机械手的.结果发生明显的改进后的系统动力学仿真分析和另一个未精制一个几乎是几乎相等.但刚度的改进的质量大大降低,说明这种方法更为有效的。
关键词: 机械手、adams、优化、动力学仿真
0 简介
并联结构机械手(pkm)是一个很有前途的机器操作和装配的电子装置,因为他们有一些明显的优势,例如:串行机械手的高负荷承载能力,良好的动态性能和精确定位的优点等.一种新型复合3一dof臂的优点和串行机械手,也是并联机构为研究对象,三自由度并联机器人是少自由度并联机器人的重要类型。三自由度并联机器人由于结构简单,控制相对容易,价格便宜等优点,具有很好的应用前景。但由于它们比六自由度并联机器人更复杂的运动特性,增加了这类机构型综合的难度,因此对三自由度并联机器人进行型综合具有理论意义和实际价值。本文利用螺旋理论对三自由度并联机器人进行型综合,以总结某些规律,进一步丰富型综合理论,并为新机型的选型提供理论依据,以下对其进行阐述。
如图-1所示 机械手组成的平面并联机构(ppm)包括平行四边形结构和线性驱动器安装在ppm.两直接驱动电机c整合交流电高分辨率编码器的一部分作为驱动平面并联机械装置.线型致动器驱动的声音线圈发动机.这被认为是理想的驱动短行程的一部分.作为一个非换直接驱动类,音圈电机可以提供高位置敏感和完美的力量与中风的角色,高精密线性编码作为回馈部分保证在垂直方向可重复性。
另一方面,该产品具有较高的刚度比串行机械手,因为它的特点和低封闭环惯性转矩。同时,该系统可以克服了柔性耦合力学弹性、齿轮、轴承、被撕咬支持,连接轴和其他零件,包括古典驱动设备,因此该机械手是更容易得到动力学性能好、精度高。
图-1 3自由度的混合结构的机械手
当长度的各个环节的平面并联机时,构决定于运动学分析和综合[4-7],机械优化设计的首要任务,应加大僵硬、降低质量.关于几个参数模型.这是它重要和必要的影响,研究了各参数对模型表现以进一步优化。本文就开展设计研究工具,通过参数分析亚当斯,又要适当的方式来获得一个轻量级的优化和小变形系统。仿真模型
adams(automatic dynamic analysis 0f mechanical system)自动机械系统动力学分析是一个完美的软件,对机械系统动力学模拟可处理机制包括有刚性和灵活的部分,仿真模型可以创造出机械手的亚当斯环境 如图-2。oxyz是全球性的参考帧,并oxyz局部坐标系,两个直流驱动电机、交流和02m o1a表示,与线性驱动器ch被视为刚性转子转动惯量电机传动的120kg/cm2。大众的线性驱动器是1.5kg,连接ab、德、03f和lj被视为柔性体立柱、横梁gk,通用公司和公里,形成一个三角形,也被当作柔性传动长度的链接是决定提前运动学设计为ab =o3f = 7cm,de=ij=7cm,gk= 7cm,gm =11.66cm,= 8.338cm。其它维度,这个数字是01a = 02m =7cm,cb=cd=hj 2.5cm。ef=eg=jk= 3cm。
虽然总平面并联机构的运动都是在水平、垂直和水平刚度必须在竖向刚度特征通常低于水平僵硬,因为它的角色在垂直悬臂梁的截面尺寸计算每一束平面并联机构和相对位置的线性驱动器是两个非常僵硬的影响因素的系统。
运动支链可分为三类:“主动链(由驱动器赋予确定独立运动的支链。一般是单驱动器控制一个自由度的运动),从动链(不带驱动器、被迫作确定运动的支链。又分为以下两种:约束链:独立限制机构自由度的从动链。冗余链:重复限制机构自由度的从动链)复合链(有单驱动器、但限制一个以上的机构自由度的支链,实际是主动链与约束链的组合)-并联机构是由这几种支链用不同形式组合起来的。动链中的约束链除了可以提高机构刚度和作为测量链外,其更主要的作用是用来约束动平台的某一个或几个自由度,以使其实现预期的运动。
图-2 仿真模型 仿真模拟结果
在本节中,平均位移的末端是用来描述动态刚度,这是在不同的配置在不同的线性驱动器向前,从最初的位置的目的地,一般的竖向位移的机械手是作为目标来研究竖向刚度,平均差别的横坐标、纵坐标点之间有一个刚性数学模型,模型,作为目标来研究水平刚度。
并联机器人的构型设计即型综合是并联机器人设计的首要环节,其目的是在给定所需自由度和运动要求条件下,寻求并联机构杆副配置、驱动方式和总体布局等的各种可能组合。国内的许多学者正致力于这方面的研究,其中比较有代表性的有如下几种方法:”黄真为代表的约束综合法;杨廷力等人的结构综合法;代表的李代数综合法。以上各种方法自成体系,各有特点,都缺乏理论的完备性。本文提出添加约束法,是从限制自由度的角度出发,增加约束,去除不需要的自由度,因每条主动链只有一个驱动装置,让其控制一个自由度,其余自由度通过纯约束链去除,这样可以使主、从动运动链的作用分离,运动解耦,有利于控制。具有三自由度的并联机床,当采用条主动支链作为驱动时,机构就需要约束另三个自由度,通过选择无驱动装置的从动链来完成,则整个机构成为有确定运动的三自由度的并联机构。黄真等提出的约束综合法对完全对称的少自由度并联机器人机构进行了型综合,完全对称的支链结构相同,都属于复合链,每条支链除都有一个单驱动器,控制一个自由度外,还应约束一个以上自由度才能使机构的六个自由度全部受控,使机构有确定的运动。
2.1 截面效应
扭转变形位移的连结将会引起的,所以,扭转常数的横截面,重力是研究装系统来研究,采取扭转刚度的垂直切片lxx不变的各个环节和梁作为设计变量的变化,从 0.1 x 105mm4 与 3.5 x 105 mm4。
图-3 不断的效果在垂直变形扭转
图-3显示了平均位移与截面扭转常数末端的各个环节和梁,根据它的变化速率的环节,是最大的,ab是链接,lj依次分别gk梁和km有在竖向刚度性能。其他的仿真结果表明,水平位移之间的差异进行比较,结果表明该模型体育智力h和刚性模型变化小就改变了恒定不变的时候扭加载惯性力的线性驱动器,但是水平位移的变化,这意味着在这种模拟竖向变形的生产水平位移系统机械手。注意端面线性驱动器的主要原因是水平变形、线性驱动器机器人是由两个节点c和h.所以,我们计算了不同的z-coordinate摄氏度之间,如图所示,在图4-扭转常数的影响差别的链接德。其次是最有效的通用和连接梁,连接o3f,梁gk有效果。
因此,应采取ab和连接区段大扭常数的免疫力,竖向刚度较大并行扭转不变的链接德也使较少的均匀性,降低线性驱动器不可以降低水平变形。
图-4 在不影响扭不变
如图-
5、6所展示的影响是区域惯性转矩的设计变量是区域刚度和惯性转矩的各个环节和梁lz,图显示增加lw卡尔减少的速度高于垂直位移的不断增加ixx扭转。这个yxx ab、梁的链接,链接o3f是iyy三个主要因素决定了竖向刚度。
图-6 所示 链接的ab、梁公里,连接03f也是其中的三个主要因素决定的均匀性线性传动装置、不同的分析结果表明,izz效果好,具有至少两个垂直和水平刚度,这意味着这种结构,具有足够的水平,降低izz刚度的链接和增加iyy ab、梁的链接,链接o3f公里的好方法,优化系统。
图-5 瞬间的惯性效应对垂直位移
图-6 转动惯量不平衡的影响
2.2影响的线性驱动器的相对位置
线性执行器的惯性是主要载荷之一,在机械手的运动,不同的相对应的垂直位置产生不同的变形,图7显示了绝对平均的最终效应垂直位移时驱动马达以恒定的加速度旋转,我们可以看到,过低或过高的相对位置会造成比格变形,最好的位置是一对z = 24毫米的地方大概是从中间环节连接o3f到 ab.图-7
影响线性驱动器的相对位置
分析改进的机械手
根据上述模拟结果,所有改进的机械手的设计,时间如下:链接截面ab,de,lj 与30mm的基础和高度,10毫米的厚度;链接o3f和矩形空心梁与30mm的基础和高度工型钢,l0mm法兰和6mm网;梁竞,通用汽车与8mm的坚实基础和30mm高的矩形。
图-8 梯形运动姿态
图-9中回应的是机械手,相比之下,图-10中提高初始的反应,在其中所有的链接和机械手的矩形截面梁的坚实基础,用30毫米,高度的差异是曲线,c和h的曲线积分,二是垂直位移的末端,改进系统中最大位移0.7um最初的0.12um相比,争论的振动激励后仍停留在o.06um±0.15% s±o.05um相比的初始变形改善系统的初始小于前者具有较少的惯性,因为在相同的步伐不断加快,保持振动瓣膜差不多一样,它对这整个系统中来说,仍然改善系统的刚度,几乎相当于初始制度,针对大规模的平面并联机构在该系统相比下降了30%,这样的初始优化是有效的。
图-9、图-10 动态响应
结论
本文设计了一种新型三自由度机械手变量的敏感性进行了研究在adams环境中,可以得出以下结论:
1)机器人具有较大的水平刚度,最终水平位移,效应主要是由机械手垂直变形造成的,因此,更重要的是增加的幅度比刚度竖向刚度。
2)参数ixx,iyy并链接'截面刚度izz有不同的效应,iyy已经对垂直刚度的影响最大,ixx在第二位的是,ixx具有在垂直刚度的影响最小,他们都较少对水平比垂直刚度刚度。3)横截面的不同环节都有不同的影响,连线竖向刚度ab和德应该使用区扭转常数和惯性力矩大,如变形、长方形、横梁km,线 03f应该使用区段形梁等重大时刻转动惯量、横梁gk,和gm 可以使用尽可能的一小部分,从而降低了质量。4)最佳的线性驱动器的相对位置可以减少变形,最好的位置是垂直的平行结构。5)改进的机械手的动态分析表明该优化设计方法研究的基础上的效率。
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