In this paper, a novel spherical parallel manipulator and its isotropic design is introduced. This manipulator has good accuracy and relatively a larger workspace which is free of singularities. Utilizing spherical configuration the forward position problem is solved by equivalent angle– axis representation and Bezout’s method which leads to a polynomial of degree 8. Two examples are given, one for isotropic and one for nonisotrpoic design. The first case results in eight real solutions, therefore, the polynomial being minimal. Using invariant form, acceleration analysis, Q2 conditions for singularity, and find infinite isotropic structures are performed. Accuracy and workspace analysis are performed and are shown to have good global conditioning index and relatively larger workspace. Using isotropic design and singularity requirements, we show the workspace of isotropic design is free of singularity.

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