Miscellaneous

Question 1

What are the industrial benefits of using parameterization to reuse engineering knowledge?

Answer 1

Shorter time – means more iterations. More iterations means better products because:
Larger amount of designs considered and evaluated in concept phase
Knowledge related to lifecycle aspects (design for: assembly, manufacturing, serviceability, environment…) can
be integrated in detail design phase
Synthesis – analysis loops can be shortened – verification feedback instant

Question 2

The Method of Influence Coefficients can be used to perform Monte Carlo variation simulations on non-rigid parts.
How does it work?

Answer 2

When doing a Monte Carlo variation simulation more than 1000 iterations have to be done
To do this with traditional FE methods would take too long time
Therefore, a FE solver is used to create a linearized model of the assembly
The linearized model is then used in the simulations
This gives a very large reduction of the simulation time (~ a factor 1000)
If the locators or support points are moved, a new linearization has to be done

Question 3

What does perceived geometrical quality depend on?

Answer 3

Visual sensitivity
geometrical form
split-line placement
Geometrical sensitivity (locator placement)
Tolerances/distributions

Question 4

What characterizes a geometrically robust assembly concept?

Answer 4

Geometrically robust concepts are insensitive to manufacturing variation

Question 5

What are the advantages of a geometrically robust assembly concept?

Answer 5

Easier process adjustment and tuning
Shorter start and ramp-up times
Global production with high and equal quality level

Question 6

What are the three types of modeling components in a multi-body system dynamic simulation?

Answer 6

Rigid bodies
Constraints (joints, motions)
Forces (gravity, spring/dampers, friction etc.)

Question 7

Mention four of the essential tasks for a PDM-system

Answer 7

Capture information at the source
Organize information
Run the information flow – when, where, what, to whom
Search and re-use information
Secure storage of information over a long time

Question 8

What is virtual geometry assurance?

Answer 8

Using computer tools to perform geometry assurance tasks on virtual product models

Question 9

Describe how virtual geometry assurance can be used in some task in the geometry development process.

Answer 9

Analyse different assembly concepts
Analyse and define robust locating systems
Simulate and verify the final demands
Virtual matching for trimming the production process

Question 10

Three different types of coordinate systems are used in virtual reality models (and also in CAD models). Specify
these and what they are used for.

Answer 10

1. World coordinate system
   Only one in each model
   The position of other objects are related to this
2. Object coordinate system
   One coordinate system per object in the model
   Positions the object relative to the world coordinate system or relative to a superseding object
3. The coordinate system of the observer (Virtual Observer)
   Makes it possible to travel around in the model