Part III: Working with Assemblies
Resolved versus unsuppressed
The terminology becomes a little convoluted here because of the relationship between the five dif-
ferent states. In parts, the feature states are easy to remember because features can be either sup-
pressed or unsuppressed. However, in assemblies, there are five states instead of two, and so
unsuppressed could mean anything that is not suppressed, which still leaves three states. For this
reason, resolved is used instead of unsuppressed when dealing with components in an assembly.
Configurations for positions
When you use configurations to display an assembly in various positions, you can do it a couple of
ways: by changing mates or by changing a layout sketch. Mates are configurable in two ways:
mates can be suppressed and unsuppressed, and angle and distance mate values are configurable
in the same way that sketch dimensions are configurable. Although creating a mate scheme that
enables you to reposition the assembly using mate suppression states and values is essential to this
method, it may not be the best approach.
Using a skeleton or layout sketch to mate parts may be a better approach, although this also has its
drawbacks. If you mate to a layout sketch, you cannot make use of Dynamic Assembly Motion. If
you use the mate scheme discussed previously, this generally means having a fully defined assem-
bly, and this also does not allow for Dynamic Assembly Motion.
As a compromise, a good way to handle this is by using one configuration for Dynamic Assembly
Motion, with one or more open degrees of freedom. You can use other configurations to fully
define the mechanism and show it in particular positions using either method. Probably the best
way to demonstrate this is with an example using the robot arm assembly.
Positioning with mates
First, take a look at positioning with mates. On an assembly such as this one, the goal is to position
the grippers. You can do this a couple of ways, both directly and indirectly. In the assembly used
for this chapter, the grippers have been rebuilt as a subassembly, which allows different types of
control. Notice that the subassembly has a configuration for the closed position and one that
allows Dynamic Assembly Motion. Also, the subassembly is being solved as Flexible. Figure 14.9
shows the assembly and the FeatureManager.
Driving the position directly
A sketch point has been added to the subassembly to precisely identify the point on the gripper
that is to be positioned. Sketch points have also been added to the main assembly to represent
parts that need to be picked up by the robotic arm.
Check the derived configurations under the default config. Notice that when you switch between
certain configurations, the parts seem to separate. Moving one of the links causes the parts to snap
back together again. This is probably because there are so many options when moving between
configurations that the software has difficulty choosing a final position. This is definitely one of the
potential problems when using configured mates to show an assembly in various positions.
