【作者】 张伟；

【导师】 周毅钧；

【作者基本信息】 安徽理工大学 ， 机械工程， 2020， 硕士

【摘要】 作为机器人的一部分,并联机构具有精度高,承载能力强,柔韧性好等特点,越来越受到许多专家的重视。最初的并联机构一般拥有六个支链的六自由度机构,最为典型的为Steward并联机构,由于它本身构型特点,其在工作时会产生支链之间相互干涉与奇异性等问题,而少自由度并联机构是并联机构的一个重要分支,由于少自由度并联机构结构简单、工作空间相对而言较大,在特定场合可以完成六自由度无法完成的工作。针对少自由度并联机构优点与可研究的价值性,提出了 2RPS/2SPC与2RPS/2SPU两种并联机构,这两种并联机构自由度都为两平移两转动(2T2R),其相同构型对称布置,并对两种机构进行自由度分析、运动学分析、工作空间分析,并把两种机构应用于液压支架并进行模态分析与围岩耦合分析,得出两种机构设计的合理性与可行性。首先,运用拓扑结构理论对两种机构构型进行分析,得出两种机构自由度特性都为两平移与两转动(2T2R),并对两种机构是否存在消极运动副进行判断,确定了两种机构的移动副都可以作为驱动副,根据基本运动链理论,进行机构的耦合度计算;运用螺旋理论分析两种机构自由度特性,并利用修正的G-K公式计算出两种机构的自由度,三种方法求出的自由度数都相同。其次,进行机构运动学分析,首先利用空间坐标变换矩阵对2RPS/2SPC并联机构进行位置反解,在位置反解的基础上得到已知四条支链的长度,然后进行位置正解;利用封闭矢量法对2RPS/2SPU并联机构进行位置反解,接着同样进行机构的正解。再运用Adams软件对并联机构进行运动学仿真,并利用并联机构反解公式在MATLAB中进行仿真,仿真得到的图形与在Adams中反解得到的图形进行比较,验证了理论求解的正确性。接着,通过极限边界搜索法求出了 2RPS/2SPC与2RPS/2SPU两种并联机构工作空间,生成工作空间三维图形与投影在坐标平面上的二维图形,两种机构工作空间都是呈对称结构,这与机构构型布置相一致。最后,把两种并联机构应用于液压支架,对2RPS/2SPC与2RPS/2SPU并联机构进行了模态分析、预应力模态分析与瞬态动力学分析,得出两种机构共振频率、变形量及围岩耦合情况,为两种机构在少自由度并联液压支架上的应用提供一定理论仿真依据,少自由度并联液压支架增加了自由度数,增大了抗侧向载荷的能力,稳定性更好。图[101]表[8]参[82]更多还原

【Abstract】 As a part of the robot,the parallel mechanism is paid more and more attention by many ex-perts because of its high precision,strong bearing capacity and good flexibility.Because of its configuration characteristics,the steward parallel mechanism will produce problems such as in-terference and singularity,and the less freedom parallel mechanism is an important branch of the parallel mechanism.Two RPS/2SPC and two RPS/2SPU parallel mechanisms are proposed,both of which are two translation and two rotation(2T2R),and the same configuration is symmetrical ar-rangement structure.The configuration analysis,kinematics analysis and workspace analysis of the two parallel mechanisms are carried outThe two mechanisms are analyzed by topological structure theory structure theory,and the degrees of freedom of the two mechanisms are two translations and two rotations(2T2R),and the existence of negative motion pairs of the two mechanisms is judged motion chain theory,the coupling degree of the two mechanisms is calculated.Secondly,the kinematics analysis of the mechanism is carried out Firstly,the spatial co-ordinate transformation matrix is used to solve the position inverse of the two RPS/2SPC parallel mechanisms,and the length of the known four branches is obtained on the basis of the position inverse solution,and then the position inverse solution of the two RPS/2SPU parallel mecha-nisms is carried out by closed vector method Then the Adams software is used to simulate the reverse solution and positive solution of the parallel mechanism,and the inverse solution formu-la of the parallel mechanism and the data calculated in the Adams of the parallel mechanism are used to simulate the MA TLAB.The simulation figure is compared with the inverse solution in the Adams to verify the correctness of the theoretical solution.Then,two kinds of parallel mechanism workspace are obtained by limit boundary search method,two RPS/2SPC and two RPS/2SPU are generated,and the three-dimensional graphics of the workspace and the two-dimensional graphics projected on the coordinate plane are gener-ated The workspace of the two mechanisms is symmetrical,which is consistent with the con-figuration of the mechanism.The two parallel mechanisms are applied to the hydraulic support The modal analysis,prestressing modal analysis and transient dynamic analysis of the two RPS/2SPC and two RPS/2SPU parallel mechanisms are carried out The resonance frequency,deformation and sur-rounding rock coupling of the two mechanisms are obtained.Figure[101]table[8]reference[82]更多还原