Kinetostatic Modeling of N-DOF Parallel Mechanisms With a Passive Constraining Leg and Prismatic Actuators

Abstract

This paper introduces several new types of parallel mechanisms with prismatic actuators whose degree of freedom is dependent on a constraining passive leg connecting the base and the platform. A general kinetostatic model is established for the analysis of the structural rigidity and accuracy of this family of mechanisms. The geometric model of this class of mechanisms is first introduced. Then, a lumped kinetostatic model is proposed in order to account for joint and link compliances. Additionally, the inverse kinematics and velocity equations are given for both rigid-link and flexible-link mechanisms. Finally, a few examples are given to illustrate the results.

Stiffness Analysis of Planar Parallel Manipulators with Serially Connected Legs

“…반면, 저자유도 공간 및 평면 병렬형 기구의 강성해석은 그 중요성에 비하여 많은 연구가 진행되고 있지 않다. Zhang 등 [11] 은 저자유도 병렬형 기구 다리에 가상 조인트를 추가하는 방법을 제시하였다. 그러나 이 방법은 가 상 조인트를 추가하는 방법이 체계적이지 못한 단점을 갖는다.…”

“…이 방법은 모델 [8][9][10] 과 달리 링크 및 베어링 의 강성도 고려할 수 있고, 역나선 방향으로 스프링이 위치해야하 는 가정이 필요 없고 [8][9][10][11][12]15] 다리가 특이 위치에 있을 경우에도 특 이값 분해를 사용 [16] 하지 않고 강성해석을 수행할 수 있다. 특히, [17] .…”

KINEMATICS, STATICS AND STIFFNESS ANALYSIS OF n(4-SPS+SP) S-PM

“…叫]. The kinematics, singularity, stiffness and dynamics of this class of PMs have been deeply i口vestigated [10]- [12]. This paper proposes a novel n( 4-SPS 十 SP) serial-PM formed by n 4-SPS 十 SP PMs connected in series.…”

Kinematics/statics and workspace analysis of a 3-leg 5-DoF parallel manipulator with a UPU-type composite active constrained leg

“…In this aspect, Zhang and Gosselin proposed n-DoF PMs with a central passive constrained leg. 8 Huang et al studied two 3-DoF PMs, i.e., a Tricept with a central UP passive constrained leg and a TriVariant with a UP active constrained leg. 24 Güursel and Bijan analyzed a 3-SPS PM with a central passive constrained spherical joint.…”

“…1,2 Among them, some 5-DoF PMs have attracted a lot of attentions for their merits, such as large workspace, larger capability of load bearing, and suitable for 3D free-form surface normal machining. [3][4][5][6][7][8][9][10][11] Generally, a conventional n-DoF PM (n < 6) includes a moving platform m, a fixed base B, n active legs, and 6-n couple structure constraints which are formed from two legs or more. Therefore, some conventional PMs may be highly sensitive to the manufacturing error due to 6-n couple structure constraints, and an unnecessary tiny self-motion of platform may be generated.…”