http://www.mcmaster.com/#
WHAT IS A WELDMENT?
http://www.voisard.com/albums/products/slides/Weldment.html
WHAT IS A WELDMENT?
http://winman.ca/portfolio/weldments.htm
WHAT IS A WELD?
WELDMENTS IN SOLIDWORKS
ROPS.SLDPRT
TRUSS.SLDPRT
WHAT IS SHEETMETAL?
support bracket.SLDPRT
WHERE ARE WE IN THE DESIGN PROCESS?
FUNCTIONAL DECOMPOSITION
DECISION MATRIX
CAD
Engineering
Simulation
ENGINEERING
SIMULATION AND
ANIMATION
QFD
ENGINEERING SIMULATION
OR
ENGINEERING ANALYSIS
OR
ENGINEERINNG MODELING
EVOLUTION OF DESIGN PROCESS
TRADITIONAL PRODUCT
SIMULATION DRIVEN PRODUCT
DESIGN PROCESS
DESIGN PROCESS
DESIGN
CAD
solid
CAD
FEA
PROTOTYPING
PROTOTYPING
TESTING
TESTING
affordable
computers
PRODUCTION
SIMULATION
Windows OS
PRODUCTION
ENGINEERING DESIGN MODELS
STRUCTURE
Descriptive and graphical
e.g. diagrams of how elements are connected and arranged
FUNCTION
Generally abstract
e.g. mathematical models
FORM
Descriptive and graphical
e.g. drawings of parts and assemblies
FORM, FUNCTION AND STRUCTURE
CAE models
STRUCTURE
Power
Supply
MIC
+9V
C1
+ R4
R3
3
2
+
4
R1
B
741
6
7
R8
R5
C
Q1
E
R2
C2
+
R6
LED
R7
LENS
Components:
741 OP AMP
R1 = 50 kW (Variable)
R2 = 1 MW
R3 = 5.6 kW
R4 = 5.6 kW
R5 = 1 kW
R6 = 50 kW (Variable)
R7 = 1 kW
R8 = 220 W
C1 = 0.1 mF
C2 = 10 mF
Q1 = 2N3904
LED
MIC : Microphone
Vcc = 9 V
MICROPHONE with two wires:
1
MIC
2
AM Light Wave Transmitter
2.2 kW
Power Supply
Output
1 mF
Ground
STRUCTURE
Pneumatic Logic Diagram
STRUCTURE
Pneumatic Logic Diagram
FUNCTION
System diagram of a sensor system
FUNCTION
Differential amplifier
INPUT
Reference value
OUTPUT
Amplifier
Motor
Rotating Shaft
Constant speed shaft
Measurement
Tachnogenerator
Shaft Speed Control
System diagram of a shaft speed control
FUNCTION
Io  cl   kl   mee lm cos  t
2
d
2
k
2
Vibration of a single degree of freedom system
3
Pl
f 
3EI y
Deflection of a cantilever beam
FUNCTION
System diagram of a car steering
FUNCTION
Ackerman steering geometry is defined by angling the steering arms so that a line drawn between both the
king pin and steering arm pivot points intersects with the centre line of the rear axle.
System diagram of a car steering
FUNCTION
Model captures FUNCTION but not FORM
Ackerman.SLDASM
FUNCTION
Transfer Function - is the input-output relationship of a system (or subsystem).
OUTPUT = TRANSFER FUNCTION X INPUT
Example:
For a gear box: output angular velocity = C X input angular velocity
where C is some constant (i.e. transfer function).
Model captures FUNCTION but not FORM
transfer function.SLDASM
FUNCTION
Model captures FUNCTION but not FORM
Oldham coupling.SLDASM
FORM – Engineering Drawings
Layout Drawing – drawn to scale but does not show tolerances, and is subject to
change as the design process continues.
FORM – Engineering Drawings
Detail Drawing – includes tolerances and indicates materials & lists special
processing requirements. Drawn in conformance with ANSI drawing standards.
FORM – Engineering Drawings
Detail Drawing – includes tolerances and indicates materials & lists special
processing requirements. Drawn in conformance with ANSI drawing standards.
FORM – Engineering Drawings
Assembly Drawing – uses an exploded view to show how some of the individual
parts fit together. Components are identified by a part number or entry on an
attached bill of materials.
FORM – Engineering Drawings
Information on a Bill of Materials:
1.
The item number or letter.
This is a key to the components on the assembly drawing.
2.
The part number.
This number is used throughout the purchasing, manufacturing, inventory
control, and assembly system to identify the component.
3.
The quantity needed in the assembly.
4.
The name or description of the component.
This must be a brief, descriptive title for the component.
5.
The material from which the component is made.
If the item is a subassembly, then this does not appear in the BOM.
6.
The source of the component.
If the component is purchased, then the name of the company is listed.
BILL OF
MATERIALS
(BOM)
Typical assembly drawing with parts list.
FORM, FUNCTION AND STRUCTURE
CAE models
COMPUTER AIDED ENGINEERING (CAE) TOOLS IN MME2259a
CAD
•
•
•
geometric modeling of parts and assemblies
drafting
visualization (eg. shading, photo-rendering)
Use of Motion Analysis is
SIMULATION TOOLS
•
Motion animation (SOLIDWorks)
•
Structural analysis (Simulation Express)
required in the Design Project
The use of Simulation Express is not
required in the Design Project.
Familiarity with Simulation Express is
required to pass CSWA (10% bonus) exam.
MOTION ANALYSIS
Deciding Which Type of Study to Use
Use Animation to create presentation-worthy
animations for motion that does not require
accounting for mass or gravity.
Use Physical Simulation to create
presentation-worthy approximate simulations of
motion that account for mass, collisions, or
gravity.
Use Motion Analysis to run computationally
strong simulations that take the physics of the
assembly motion into account. This tool is the
most computationally intensive of the three
options. The better your understanding of the
physics of the motion you require, the better
your results. You can use Motion Analysis to run
impact analysis studies to understand
component response to different types of forces.
MOTION ANALYSIS
DIFFERENCE BETWEEN A MECHANISM AND A STRUCTURE
Structure is firmly supported, mechanism is not.
Mechanism moves without having to deform its components.
Mechanism components move as rigid bodies. Generally, a
mechanism is designed to move. Mechanism has Rigid Body
Motions (RBM).
Structure does not have Rigid Body Motions, any movement of a
structure must involve deformation.
It may be one time deformation when the static load is applied or
vibration about its neutral position (point of equilibrium). Generally
a structure is designed to stand still.
DIFFERENCE BETWEEN A MECHANISM AND A STRUCTURE
STRUCTURES
MECHANISMS
COMMON KINEMATIC PAIRS
(MECHANISM COMPONENTS)
Revolute
cylindrical
Spherical
1 DOF left
2 DOF left
3 DOF left
Translational (prismatic)
Planar
1 DOF left
3 DOF left
RIGID BODY MOTION
RIGID BODY MOTION
How many rigid body motions?
MOTION ANALYSIS: ANIMATION OF MOTION
quick return.SLDASM
STRUCTURAL ANALYSIS IS NOT NECESSARILY STATIC ANALYSIS
STRUCTURAL ANALYSIS: ANIMATION OF MODES OF VIBRATION
tunning fork.SLDPRT
MOTION ANALYSIS: ANIMATION OF MOTION
http://www.eng.uwo.ca/designcentre/FEA%20resources/
STRUCTURAL ANALYSIS – Simulation Xpress
In class demonstration
HUMAN FACTORS IN DESIGN
ANTHROPOMETRIC DATA
Vast amount of information is available on-line
WHAT IS A PERCENTILE?
Percentile
One of a set of points on a scale arrived at by dividing a group into parts in
order of magnitude.
For example, a score equal to or greater than 97 percent of those attained
on an examination is said to be in the 97th percentile.
Estimates proportions of the data that should fall above and below a given
value.
SIZE VARIATIONS IN A POPULATION
Taller than 97.5%
of population
Taller than 50% of
population
Taller than 2.5% of
population
In general body heights and body lengths do vary uniformly in
a population because they depend upon bone structure.
WEIGHT VARIATIONS IN A POPULATION
In general weights and widths may not vary uniformly since these
measurements depend upon age, amount of body fat, musculature, etc.
ANTHROPOMETRIC DATA
ANTHROPOMETRIC DATA
Civilian populations:
97.5 percentile
50 percentile (median)
2.5 percentile
ANTHROPOMETRIC DATA
Range-of-Motion
R.J. Eggert, Engineering Design, Prentice-Hall:Upper Saddle River NJ, 2005, pp. 262.
ANTHROPOMETRIC DATA
Range-of-Motion
R.J. Eggert, Engineering Design, Prentice-Hall:Upper Saddle River NJ, 2005, pp. 263.
ANTHROPOMETRIC DATA
Range-of-Motion
R.J. Eggert, Engineering Design, Prentice-Hall:Upper Saddle River NJ, 2005, pp. 264.
ANTHROPOMETRIC DATA
Average Human Strength
for Different Tasks
ANTHROPOMETRIC DATA
Muscle Strength for 95th
Percentile Males
R.J. Eggert, Engineering Design, Prentice-Hall:Upper Saddle River NJ, 2005, pp. 258.
ANTHROPOMETRIC DATA
Static Muscle Strength
for Vertical Pull
R.J. Eggert, Engineering Design, Prentice-Hall:Upper Saddle River NJ, 2005, pp. 2598.
3D Contents Central