ABSTRACT
C H A P T E R 6
This chapter is devoted to the kinematic analysis of planar mechanisms that employ turning and sliding joints only, also known as linkage mechanisms or linkages in short. Numerous such mechanisms can be analyzed by decomposing them into input link(s), plus subassemblies of links and joints that stand alone have zero degrees of freedom (DOFs). ¬ese subassemblies are known as Assur groups, named a®er the Russian engineer L. V. Assur who discovered them at the turn of the twentieth century. When such a zero DOF subassembly consists of two links and three joints, known as dyad, the corresponding kinematic equations can be solved analytically rather than numerically, and therefore allow for very fast computer implementations. ¬e kinematic equations of all known dyads are derived in this chapter. ¬ey were also programmed in a number of Pascal procedures gathered in unit LibAssur available with the book. By calling these procedures in the same order in which the actual linkage mechanism has been formed, starting with the input member(s), the position, velocity, and acceleration of any moving link or point of the mechanism can be calculated, while supplementary, the whole mechanism can be animated over a given motion range.
