Computer-aided mobility analysis of parallel mechanisms

Abstract

To determine mobility properties is one of the most challenging issue in the analysis and synthesis of parallel manipulators (PMs). However, currently, the most used methods mainly rely on experiences and manual analysis, which led to inefficient implementation. The motivation of this paper is to present an automatic mobility analysis algorithm and software package for the researchers and designers with an effective and practical means. According to the topological design theory of PMs based on position and orientation characteristic (POC) equations, this paper proposes a set of computer algorithmic rules and procedures for automated mobility analysis of PMs in the most user-friendly and efficient way. Firstly, a complete digital information model for topological structures which has a mapping relationship with the POC of a PM is proposed. This model not only describes the dimension of the motion outputs, but also includes the mapping relationship between the output orientation and the axes of the kinematic joints. Secondly, algorithmic rules are established that convert the union and intersection operations of POC into binary logical operations and then the detailed algorithmic procedures for an automatic mobility analysis are presented. In what follows, a corresponding software for automatic mobility analysis is described. The software package is equipped with a GUI that facilitates the input and allows the visualization of the results. Finally, four typical examples are provided to show the effectiveness of the software package for most of parallel mechanisms (not including some paradoxical mechanisms).

Computer aided design of a single degree-of-freedom six-bar mechanism via Monte Carlo layered optimization method

“…Given the escalating intricacy of mechanism design, it is increasingly challenging for regular engineers to autonomously accomplish the design process. Hence, the imperative is to develop software that aids engineers in expeditiously designing mechanisms meeting specified requirements [ 28 ] and fostering the creative inclinations of designers [ [29] , [30] , [31] ]. The use of computer-aided design software is prevalent in the design of transmission mechanisms [ [32] , [33] , [34] ].…”

Power Flow in Coupled Three-Row Series-Parallel Planetary Gear System, Part I: Without Power Losses

“…They consist of at least two subsystems (units) in the form of elementary 2KH planetary gears connected in parallel and possibly in series. Each of the subsystems connected in parallel has a mobility equal to two [1][2][3][4][5][6]. This means that all of the gears are moving along with the carriers.…”

An approach for mobility and force/motion transmissibility analysis of parallel mechanisms based on screw theory and CAD technology

“…Gile et al 27 developed a teaching system focusing on the inverse and forward kinematic analysis of PMs, LABEL, by using the Easy Java Simulations. More recently, according to the topological design theory of PMs based on position and orientation characteristic (POC) equations, Zhu et al 28 proposed an automatic mobility analysis algorithm and software package for the researchers and designers with an effective and practical means. The authors developed a complete digital information model and algorithmic rules for mapping the topological structure of a limb or a PM into their POC, thus the mobility analysis can be performed by a computer program without manual intervention.…”