Begin by defining a surface named Board for the circuit board.
Select Both sides in the prompt area to specify that the surface is
double-sided. In the Model Tree, double-click the Constraints container; define a tie constraint named
TopChip. Select Board as the
main surface and TopChip as the secondary node region. Toggle
off Tie rotational DOFs if applicable in the Edit
Constraint dialog box since only the effects of the chip masses are of interest,
and click OK. Yellow circles appear on the model to represent the
constraint. Similarly, create tie constraints named MidChip and
BotChip for the middle and bottom chips.