This contribution presents a mobility criterion applicable to parallel platforms based on an analysis of the Jacobian matrices associated with the platform legs. It is important to note that this criterion is based on an analysis of the subalgebras of the Lie algebra, se(3), also known as screw algebra, of the Euclidean group, SE(3). The mathematical foundations of the method have been already presented in [1]. In this contribution it is shown that, employing a basic knowledge of linear algebra, it is possible to compute the correct mobility of a wider class of parallel manipulators, including the mobility of kinematically deficient parallel platforms and platforms with inactive pairs. Moreover, the criterion computes the passive degrees of freedom in parallel platforms. Finally, it should be emphasized that, unlike other attempts to develop a mobility criterion, the criterion developed in this contribution does not require any consideration of reciprocal screws.
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