Parallel kinematic machine design with kinetostatic model

Abstract

In this paper, a new method – named lumped kinetostatic modeling – to analyze the effect of the link flexibility on the mechanism's stiffness is provided. A new type of mechanism whose degree of freedom (dof) is dependent on a passive constraining leg connecting the base and the platform is introduced and analyzed. With the proposed kinetostatic model, a significant effect of the link flexibility on the mechanism's precision has been demonstrated. The influence of the change in structure parameters, including material properties, on the system behavior is discussed. In the paper, the geometric model of this kind of mechanism is first introduced. Then, a lumped kinetostatic model is proposed in order to account for joint and link compliances; some results and design guidelines are obtained. Finally, the optimization of the precision is addressed using a genetic algorithm.

A novel calibration method of parallel kinematic manipulators based on multi-population coevolutionary neural network

“…(1-r (l-tIT)b) (11) where, r is a random between [0, 1], T is the maximal evolutionary generation, b is a system parameter which is usually equal to 2.…”

“…Due to their intrinsic advantages in the factors of pay load, stiffiless, accuracy, operational velocity and acceleration compared with the traditional serial counterpart [1][2][3][4][5][6][7][8], parallel manipulators have been applied to various industrial fields such as machine tools, motion simulators, micro robots, medical devices and physical sensors [9][10][11][12][13][14][15]. However, the mechanical structure of parallel robotic manipulator is considerably complicated since it is constituted with many independent motion chains rather than one single link, thus increasing the error sources and error probability.…”

Stiffness analysis and comparison of a Biglide parallel grinder with alternative spatial modular parallelograms

“…Generally, the link flexibilities have been taken into account during the development of the VJM approach, where the link is simplified as a flexible-link lumped parametric model. [6][7][8] Combining the advantages of the foregoing approaches, Pashkevich et al proposed a stiffness modeling method named as virtual spring approach, which can be applied to the manipulator at both unloaded equilibrium condition 9 and loaded case. 10 In this approach, the link flexibility is replaced by localizing a n-dofs virtual spring that is associated with the mobilities describing both the translational and rotational deflections and the coupling between them, where the spring compliance is evaluated based on the concept of the Finite Element Analysis (FEA) approach.…”

Design, analysis, and stiffness optimization of a three degree of freedom parallel manipulator

“…[1][2][3][4][5][6] Examples of this type of robot can be found in the motion platform for pilot training simulators and the positioning device for high-precision surgical tools. Recently, researchers have been trying to utilize these advantages to develop parallel robot-based multi-axis machining tools and precision assembly tools.…”