Singularity Analysis of Single-dof Spherical Mechanisms Using Instantaneous Poles
نویسندگان
چکیده
Instantaneous poles are the spherical counterparts of instant centers; however, they are not completely used to study the kinematic behavior of spherical mechanisms. Instantaneous kinematics of a mechanism becomes undetermined when it is in a singular configuration (singularities); this indeterminacy has undesirable effects on static and motional behavior of the mechanism, so these configurations must be found and avoided. This paper presents a new geometrical method to find singularities of single-dof spherical mechanisms. First, mechanical advantage of singledof spherical mechanisms is obtained using the concept of instantaneous poles; and then it is used to find geometric conditions corresponding to each type of singularities, occurring in this class of mechanisms.
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