Citation: | HUANG Xiguang, HUANG Xu. Direct kinematics of a spatial parallel mechanism based on conformal geometric algebra[J]. Journal of Beijing University of Aeronautics and Astronautics, 2017, 43(12): 2377-2381. doi: 10.13700/j.bh.1001-5965.2016.0917(in Chinese) |
An algorithm is proposed for the direct kinematics analysis of a spatial general 3-RPS parallel mechanism based on conformal geometric algebra (CGA). The angle between the axis of an arbitrary kinematic chain and the plane of the fixed platform can be regarded as the unknown variable. The mathematical expression of the position of the spherical joint connecting the moving platform with the kinematic chain can be expressed in the unknown variable based on CGA. The outer product of two space balls and a flat surface are constructed two times, and the corresponding points of the remaining two vertices of the moving platform are obtained respectively. The 16th degree input-output polynomial equation in the unknown variable is straightforwardly obtained by distance formula and all 16 sets of closed-form solutions can be achieved. The algorithm avoids the use of rational angles or matrices, and complex computations for nonlinear and multivariable equations. A numerical example is given to demonstrate geometric characteristics of the motion and the algorithm is intuitive.
[1] |
黄真, 赵永生, 赵铁石, 等.高等空间机构学[M].北京:高等教育出版, 2006:141-166.
HUANG Z, ZHAO Y S, ZHAO T S, et al.Advanced spatial mechanism[M].Beijing:Higher Education Press, 2006:141-166(in Chinese).
|
[2] |
HUNT K H.Structural kinematics of in-parallel-actuated robot-arms[J].ASME Journal of Mechanisms Transmissions and Automation in Design, 1983, 105(4):705-712. doi: 10.1115/1.3258540
|
[3] |
LEE K M, SHAH D.Kinematic analysis of a three-degree-of-freedom in-parallel actuated manipulator[J].IEEE Journal of Robotics and Automation, 1988, 4(2):354-360. http://ieeexplore.ieee.org/document/796/
|
[4] |
NANUA P, WALDRON K J, MURTHY V.Direct kinematic solution of a Stewart platform[J].IEEE Journal of Robotics and Automation, 1990, 6(4):438-444. doi: 10.1109/70.59354
|
[5] |
FANG Y, HUANG Z.Kinematics of a three-degree-of-freedom in-parallel actuated manipulator mechanism[J].Mechanism and Machine Theory, 1997, 32(7):789-796. doi: 10.1016/S0094-114X(97)00008-6
|
[6] |
李树军, 王阴, 王晓光.3-RPS并联机器人机构位置正解的杆长逼近法[J].东北大学学报, 2001, 22(3):285-287. doi: 10.3321/j.issn:1005-3026.2001.03.014
LI S J, WANG Y, WANG X G.Forward position analysis of 3-RPS in-parallel manipulator using self-modified successive approximation method[J].Journal of Northeastern University, 2001, 22(3):285-287(in Chinese). doi: 10.3321/j.issn:1005-3026.2001.03.014
|
[7] |
韩方元, 赵丁选, 李天宇.3-RPS并联机构正解快速数值算法[J].农业机械学报, 2011, 42(4):229-233. http://industry.wanfangdata.com.cn/dl/Detail/Periodical?id=Periodical_nyjxxb201104046
HAN F Y, ZHAO D X, LI T Y.A fast forward algorithm for 3-RPS parallel mechanism[J].Transactions of the Chinese Society for Agricultural Machinery, 2011, 42(4):229-233(in Chinese). http://industry.wanfangdata.com.cn/dl/Detail/Periodical?id=Periodical_nyjxxb201104046
|
[8] |
王进戈, 范丽华, 徐礼钜.3-RPS并联平台机构的位置正解与奇异构形分析的数值-符号解[J].机械设计, 2005, 22(5):15-19. http://www.cqvip.com/QK/93364X/200505/15632355.html
WANG J G, FAN L H, XU L J.Positional forward solution and numeric-symbolic solution of singular configuration analysis for 3-RPS parallel platform mechanism[J].Journal of Machine Design, 2005, 22(5):15-19(in Chinese). http://www.cqvip.com/QK/93364X/200505/15632355.html
|
[9] |
SCHADLBAUER J, WALTER D R, HUSTY M L.The 3-RPS parallel manipulator from an algebraic viewpoint[J].Mechanism and Machine Theory, 2014, 75:161-176. doi: 10.1016/j.mechmachtheory.2013.12.007
|
[10] |
LI H, HESTENES D, ROCKWOOD A.Generalized homogeneous coordinates for computational geometry[M].Berlin:Springer, 2001:27-76.
|
[11] |
LI H, HESTENES D, ROCKWOOD A.Spherical conformal geometry with geometric algebra[M].Berlin:Springer, 2001:61-76.
|
[12] |
LEO D, DANIEL F, STEPHEN M.Geometric algebra for computer science, an object-oriented approach to geometry[M].Burlington:Morgan Kaufmann, 2007:15-30.
|
[13] |
HESTENES D.New foundations for classical mechanics[M].Dordrecht:Kluwer Academic Publishers, 2002:53-96.
|
[14] |
倪振松, 廖启征, 魏世民, 等.空间一般6R机械手位置反解的新方法[J].北京邮电大学学报, 2009, 32(2):29-32. http://www.buptjournal.cn/CN/abstract/abstract506.shtml
NI Z S, LIAO Q Z, WEI S M, et al.New algorithm for inverse kinematics analysis of general 6R serial robot[J].Journal of Beijing University of Posts and Telecommunications, 2009, 32(2):29-32(in Chinese). http://www.buptjournal.cn/CN/abstract/abstract506.shtml
|
[15] |
JAIME G, HPRACIO O, JOSE M R.Kinematics of 3-RPS parallel manipulators by means of screw theory[J].International Journal Advance Manufacture Technology, 2008, 36(5):598-605. doi: 10.1007/s00170-006-0851-5.pdf
|