Through dynamic simulation of the cross-hinge four-bar mechanism. it is found the primary reason for unbalance of the mechanism results from the unequal swing angle of driving link and driven link. To simplify analysis and calculation. a spatial switching approach was proposed to switch nonlinear problem into linear problem. https://www.bekindtopets.com/mega-grab-Freetress-Crochet-Braid-DEEP-TWIST-14-Inch-save-more/