CGT 163 Exam 1

**In modern design and manufacturing organizations, which of the following items tends to be used to communicate design information between groups?**

3D Models

**Which of the following statements best characterizes the current state of engineering documentation?**

It is used throughout the product lifestyle in various forms

**Which of the following best describes the needs for engineering documentation?**

Specification of technical and procedural information, archival of design ideas and legal status, and standardized forms of communication and information presentation

**Which of the following items best describes the role of CAD in an organization?**

CAD enables communication and collaboration between groups

**Which of the following is NOT a key characteristic of a model-based enterprise?**

Drawings are used as a basis of communication

**Which of the following is an advantage of working with 3D models over 2D drawings?**

3D models are easier to understand and interpret, facilitate communication with non-technical audiences, and faciliate identification and remediaiton of errors.

**Models with gaps, openings and edges that have only one face merging with them are examples of which type of geometry?**

Non-manifold

**In feature-based modeling, geometry that describes certain aspects of the shape of the 3D model, with no implied relationship to any function or manufacturing method is called ____**

Form feature

**Which of the following is NOT a common technique to create swept solids from 2D sketches?**

Constant Sweep

**When planning a modeling strategy, an important factor that should be considered to determine design intent is _____**

anticipated changes, how the part will be manufactured, how the part will interact with other components of the assembly

Which of the following is not part of a typical CAD interface?

Coding space

Before beginning a new design, it is important to consider ___

Measurment system, engineering standard, system preferences

High-end and high-performance CAD systems are great but have drawbacks too. Which is biggest drawback?

They are expensive, require high-end harware, and have a steep learning curve

Which of the following is a typical predefined view in a CAD system?

Isometric view

How many orthographic views are there in 3D space?

6

Which of the following statements about parametric sketching is FALSE?

When defining the shape of a sketch, before the application of constraints, sketches must be drawn accurately

Which of the following is NOT a common tool for editing sketch entities in CAD?

Wrap

The first step to create a sketch is to ____

Select a sketch plane

A sketch in which a line is drawn tangent to an arc will only be parametric if…

The coordinates of the tangency point are determineda t the moment the geometric contraint is established, and the tangency condition itself is also saved

Which of the following statements about parametric sketching is FALSE?

Adding a redundant contstrain to a fully defined sketch will always over-define the sketch

A 2D sketch can be used to generate ____

Extrusions, revolutions, and sweeps

Which feature uses multiple 2D sketches and a guide curve to create or remove geometry?

Loft

In parametric solid modeling, the operation known as revolution is a particular case of _____

Fixed profile non-linear sweep

Which of the following statement about modeling best practices is FALSE?

When multiple options are availible to create a particular feature, the strategy that minimizes portability should be selected

Which of the following commands is designed to make a molded part easier to remove for its mold?

Draft

Which industrial revolution is characterized by the use of computers and new communication technologies?

Third industrial revolution

A digital enterprise ____

uses digital technology

Which of the following terms describes the communication framework that connects digital data flows and provides a complete view of an asset’s data throughout its entire lifecycle.

digital thread

Which of the following systems track digital data used for manufacturing primarily on the plant floor

MES

The decision to determine whether a part will be manufactured in-house or purchased from a supplier is known as ____

Make-Buy

Which of the following statements about product data files is FALSE?

Product data files are limited to geometry

All of the following are primary functions of PDM except…

Manage product structures

Third generation PDM systems appeared in the ____.

2000s

Where do Physical files stored in an enterprise PDM system reside?

Vault server

What process is used to identify the list of all the parts, assemblies, and projects in an enterprise that might be affected by an engineering change order?

Impact analysis

First Industrial Revolution

Transition from manual production methods to mechanical production equipment fueled by new power sources

Second industrial revolution

Electricity became available and mass produciton became widespread

Third industrial revolution

Expansion of computers, new communicaiton technologies, and their effect on production

Fourth industrial revolution

emergence of digitalization (internet)

Digital Enterprise

Organizaiton managing and controlling data in digital formats for a competitive advantage

Enterprise Resource Planning (ERP)

manages digital data such as cash, materials, and human resources

Customer relationship managment (CRM)

handles digital data ralated to attracting and retaining customers

Supply Chain Managment (SCM)

coordinates digital data involved with vendors

Manufacturing Execution Stystems (MES)

track digital data used for manufacturing primarily on the plant floor

Product Data Managment (PDM)

controls and manages digital product data throughout a product’s lifestyle

PLM

extends the scope of PDM to include each physical product produced from a design

Make decision

Parts made in house

Buy decision

Parts purchased from a supplier

First generation of PDM software

1980s

Primary functions of PDM system

Organize and control data, search and retrieve data, manage and track changes, manage data repositories, manage security

Secondary functions of PDM

Relate data by project, manage product structure, workflows, metrics and reporting, data sharing and visualization

Data repository/vault

part of PDM system where physical files are stored

Workflow

used to implement, automate, and document business processes in a PDM system

Digital thread

combination of the information flowing through the enterprise, the software used to create and edit the information, and the computing and networking architecture to move, secure, and store it

product lifestyle managment

idea of actuvely managing and curating the digital product and process data that is created and used during the product lifecycle

Model Based definition (MBD)

Requires the 3D model to be used as the authorotative source for geometry definition of the product

Advantages of 3D over 2D drawings

Easier to understand/interpret, more flexible, richer and facilitate the identification and remediation of design errors, reusable

Solid model

Includes information about the inside and outside of the object (does not represeent as an empty shell with no thickness)

Manifold geometry

3D shaoe where every edge always has two faces merging into it and all normal vectors point the same direction

Normal vector

a vector which is always perpendicular to the face

Types of non-manifold geometry

Open solids, dangling faces, invalid connected geometry, self-intersecting geometry, opposite normals

Types of boolean operations

Union, difference/subtraction, intersection

Union boolean

combines two overlapping solids to make one solid

Difference boolean

removes overlapping volume between two solids

intersection boolean

creates solid model out of the overlapping volume of two solids

Modeling/specification/design/feature tree

mechanism used to represent the modeling sequence in history-based CAD systems

Linear sweep

3D solid created by sweeping a 2D sketch along a straight path

Non-linear sweep

3D solid created by sweeping a 2D sketch along a curved path

Revolution

Type of non-linear sweep where path is defined as a full/partial circle

Fixed profile sweep

3D solid created by sweeping a single profile (identical cross-sections)

Variable profile sweep/ loft

3D solid created by specifying at least two of its cross sections

Feature based modeling

geometric contruciton method where models are created by defining and combining higher-level entities

Design feature

geometric characteristics which serve a particular purpose related to the funciton of an object

Geometric/form features

geometry that defines certain aspects of the shape of the 3D model, with no implied relationship to any function of manufacturing method

Manufacturing features

geometric characteristics that result from specific machining operations (ex. draft)

parametric modeling

ability of a CAD system to use dimensions, properties, and relationships to define, manipulate, and drive the geometry of a model

Three main types of cosntraints

Dimensional, geometric, algebraic

Five basic elements of a CAD user interface

Menus, toolset, model tree, viewport, message area

Parametric sketching

the creation of 2D geometry which will be used as the basis for generating 3D solid geometry

Parametric vs non parametric drawings

Parametric drawings are constrained so that all geometry will update when parameters are changed

In a fully defined sketch, the number of contrained relationships ___ the degrees of freedom (DoF)

equals