Abstract: Based on the pseudo-rigid-body model and unitary dimension of the kinematic parameters, the dimensional model of the 3-RUU micro-motion parallel mechanism is established, on which all the possible dimensional parameter combinations of the 3-RUU micro-motion parallel mechanism are expressed in a closed region and each point in the region corresponds a cognation of mechanisms having the same or similar kinematic characters. The motion property of the micro-manipulation is analyzed, three kinematic evaluation indexes of the micro-motion mechanism including the workspace volume value, workspace shape value and condition number of the constant Jacobian matrix are presented, and the performance index atlas describ- ing the relationships between the dimensional parameter combi- nations and mechanism performances are protracted based on the proposed dimensional model and evaluation indexes.

Key words: 3-RUU micro-motion parallel mechanism, Dimensional model, Performance atlas, Performance index