Designing End-Effectors Calculation example : When calculating the moment of inertia of a complicated shape, divide it into simple parts as much as possible for easier calculations. As shown in the figure below, divide the end-effector into three parts ( , , ). (1) Moment of inertia around J6 Moment of inertia around J6 of : I 1 (from 3 and 5 in Table 2-3) Table 3-5 Center of gravity of Moment of inertia around J6 of : I 2 (from 1 and 5 in Table 2-3) Table 3-5 φ Moment of inertia around J6 of : I 3 (from 1 and 5 in Table 2-3) Table 3-5 Center of gravity of Center of gravity of Moment of inertia around J6 of entire end-effector: I J6 Unit:
mm (2) Moment of inertia around J4 and J5 For the end-effector shown below, the moment of inertia around J4 and J5 can be calculated according to the same formula. Moment of inertia around J4 and J5 of : I 1 (from 3 and 5 in Table 2-3) Table 3-5 ((0.08 + 0.005) 2 +0.01) Moment of inertia around J4 and J5 of : I 2 (from 2 and 5 in Table 2-3) 1.03 Ч 10 -3 [kgm 2 ] Table 3-5 80 ((0.08 + 0.01 + 0.02) 2 +0.04 2 ) 1.39 Ч 10 -3 [kgm 2 ] Moment of inertia around J4 and J5 of : I 3 (from 2 and 5 in Table 2-3) ((0.08 + 0.01 + 0.05) 2 +0.05 2 ) Table 3-5 2.30 Ч 10 -3 [kgm 2 ] 80 Moment of inertia around J4 and J5 of entire end-effector: I J4 , I J5 2.54 Ч 10 -2 [kgm 2 ] Figure 2-7.
Moment of Inertia Calculation Examples Adept Viper s1300 Robot User’s Guide, Rev B 31 Robot flange center 0 0 Around J6