NEES Network for Earthquake Engineering Simulation

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Network for Earthquake
Engineering Simulation (NEES)
Design Review
12/07/2012
ARMS 1098B
http://epicspurdue.wix.com/nees
1
Agenda
•
Introduction
•
Overview of NEES
•
Clients needs and requirements
Project overview
Project 1: Shake Table
Project 2: Interface
Open Discussion
•
•
•
•
2
Project Partner
NEES
Network for Earthquake
Engineering Simulation
14 Large scale test facilities dedicated to research needed
to reduce risks caused by earthquakes and tsunamis
3
Our clients from NEES
Dr. Keith Adams
Director of Education Outreach and Training
Pamela McClure
Education Outreach and Training
207 S. Martin Jischke Dr, Suite 301
West Lafayette, In 47907
4
NEES EOT – Client Goals



Increase public awareness of NEES, its research
and its mission
Bring science and engineering to classrooms
Raise student’s interest in earthquake engineering
and science
5
Popular NEES Outreach Activity
Make Your Own Earthquake System
PC Display
PC
Platform w/
accelerometer
Developed at UC Santa Barbara by Dr. Sandra Seale
6
Existing Commercial Shake Table

Current use of MTS shake Table



Demonstrate dynamic motion
Be used with design competitions
Constraints

expensive, immobile
7
General Goals


Develop a low cost, controlled motion table
(shake table)
Supports three modes
1.
2.
3.
Harmonic motion with variable frequency and
amplitude
Make your own earthquake input to control motion
Replicate prior earthquake motion
8
Customer and Technical Requirements
#
Customer defines needs
Technical requirements
Minimize number of exposed gaps that could
pinch number of sharp edges
minimum lift requirement (<50 lbs)
Run continuous demonstration of twin KNEX for
60 minutes
10
Safety – won’t harm children (ST)
10
Portable size
10
Durability
9
Anchor the table to the table
No slip of shake table from mounting surface
9
Rigidly mount physical models
9
Easy to mount physical models
8
Easy to disassemble
No slip of physical model from table
1 person can point model in less than 30 seconds
(no more than 4 steps)
1 person can disassemble and store in less than 5
minutes
8
Easy to manufacture
Requires basic tools to assemble
8
8
Easy to repair
Variable harmonic frequency
Simple user interface to input commands for
freq/amp
Access major components in one step
0-10 Hz +/1 .25 Hz
1 pages instructions – < 5 minutes to learn to
operate
9
Customer’s Goal

Forced motion system
Physical
Models
Interface
Shake table
Visual display and
controller
Table
Jump Platform
Sensor
Power
10
Shaketable Team

Project Leader


Bryan Routt- Freshman, Engineering
Project Members






Sarah Hacker- Freshman, Engineering
Sami Labban- Freshman, Engineering (Partner Liason)
Harsh Limbasia- Freshman, Engineering
Karan Talathi- Freshman, Engineering
Kenneth Holmes- Freshman, Engineering
Alexander Newman- Freshman, Engineering
11
Target performance

Demonstrate side by side performance of two 5
story KNEX models equipped with


Tune mass damper
Cross bracing support
12
Shaketable Structure

80/20 Aluminum Frame



Inexpensive
Easy to assemble
Very sturdy
13
Shaketable Structure

Suction Cup Feet


Simple way to mount
the whole structure to a
surface.
Very cheap and easy to
use.
14
Shaketable Structure

Rails


Repurposed original rail
mounts
Added small ¼ inch
square to bolt on to 80/20
frame. EPICS
15
Shaketable Structure

Aluminum Back Plate


Sturdy mount for MDF
wall and motor
Clean look for the outside
of the structure.
16
Shaketable Structure

Motor Mount


Motor sits in ¼ deep hole
Screws run all the way
through from the outside
aluminum plate into the
back of the motor.
17
Shaketable Structure

Rack and Pinion


Rack epoxied to plate on
bottom of slider
Allows for slider to be
reused in future designs.
18
Decision Matrix for Mounting
Platform
Value
Factor
Details
9
Easily removable/
interchangeable
The platform can be removed or
exchanged for a different type of
connection
8
Durable
Light to medium heavy structures
can be attached to platform
without breaking
9
Ease of use, easy
attachment of structures
K’nex structures can be attached
easily and securely to shaketable
3
Difficulty of construction
Depends on the skill level and
equipment available to the
fabricator
19
Mounting Platform




Original peg board from
MTS powered table
Works well with K’nex
system
Board screws into
shaketable platform so it can
be removed and exchanged
for another part
Relatively easy to make and
durable
20
Component Mounting
•
Components to be Mounted
•
•
•
•
•
Arduino board
Motor driver
Motor
Components mounted to
maximize space between
components.
Isolate electronic
components from Board
•
•
Rubber Spacers
Screws into MDF backplane
21
EPICS NEES Interface
Design
Jingye Liu (Project leader)
Dongyang Fu
Zachary Golden
Andrew Grosinger
Nikhilgandhi Manojkumar
22
Introduction





Overview
Microcontroller
Driver Circuit
Circuit Shield
User Interface
23
Overview
Laptop
Visual Feeback
Input requests
(microC power)
Accelerometer
Sensor
Signal and
Power
Mount/
Housing
microC
Low current
signal
Motor
driver
Mounting
High
current
Motor
Power
24
Enhancement for the MYOE
Physical
Models
Visual
Display
User
Interface
Jumping
Platform
Sensor
Input
QNC?
Mounting
Mechanism
Controller
Interface
Shaking
Platform
Motion
Mechanism
25
function
Means 1
Means 2
Means 3
Sensor
QNC
Analog 1
WII
microC
Arduino
PIC series (prefab
board)
Hand built
Motor Driver
Motor Shield
Purchase 2
Hand built
Motor (stepper)
Small version
Position sensor
Limit switch
Potentiometer on
motor shaft
none
Input requests
Frequency/Amplitude
Mode Selection
Run/Stop
Laptop
Potentiometer
switches
Visual Feedback
Computer screen
LCD
LEDS
DC Power supplies
Batteries
AC/DC Power
supplies (wall)
AC/DC in
contained in
interface boc
Mean
s
lights
26
function
Means 1
Means 2
Interface mounting
Labtop computer
Plexiglass housing
microC housing
Shake table housing
Plexiglass housing
Motor Drive housing
Shake Table housing
Power supply housing
Wall mount PowerSup
Means 3
Mean
s
27
Accelerometer



ADXL 335
Measure acceleration from jump platform
Send signal to micro controller
28
Microcontroller and Code





Receive Frequency from Accelerometer/Manual
User Input
Convert Frequency
Send Command to
Driver Circuit
Control Direction of the Motor
Code in “Sketch”
29
Micro Controller Logic
Harmonic Mode
No
Compute steps
Move Motor
Check inputs
Update Display
Read Sensor
Data
Compute Steps
and Move Motor
Accordingly
Check inputs
Update Display
Start And Wait
for Input
MYOE Mode
Yes
Stop ?
Yes
Stop ?
No
30
Driver Circuit


Two Options for Motor Driver
Stepper Motor
Current ROB-10267
31
Wiring Interface
ACC 2
Motor
Driver
ACC 1
Shield
Mounted
X1
Y1 Z1 X2
Y2 Z2
G 5v
Arduino
8
9
32
Graphic Interface
Computer
C#
33
Budget Report
34
Hardware Costs
4 ft length aluminum (80/20)
Bolts
!ft Square Aluminum Sheet
Suction cups (2 packs of 4)
Rack and Pinion
Plexiglass
K'nex
TOTAL
$42.60
$18.50
$20.11
$15.98
$55.00
$30.00
$19.97
$202.16
Interface Costs
Arduino Board
Stepper Motor
Accelerometer
Wires
CAT5 Cable
Easy Driver
TOTAL
Gross Total
$25.00
$14.95
$15.00
$1.20
$4.99
$15.00
$61.14
$339.44
Optional Costs
Pots and Switches
Motor Shield
QCN
Plywood
Total
$24.09
$34.99
$45.00
$2.00
$445.52
35
Value Added Project

Team investigated to extension to the project


Alternative low cost, controlled motion control table
Accelerometer Mounting on K’nex structures
36
Alternative Low Cost
Controlled Motion Table
37
Premise


Could the existing low cost version be interfaced
with the controlled motion system?
Issues


Need to increase durability
Potential to improve portability
38
Make Up





PVC Base
Modified aluminum drawer slides
Plywood on drawer slides
Bungees on underside to counter input force and
center table.
Motion control


Hand operated
DC motor and off-center CAM – controlled by Arduino
system designed by interface team.
39
Parts











PVC pipes (1.5’ x 1.5’ x 1.5’’) and 90ᵒ Elbows
PVC cement 
Ply Wood (1.5’ x 1.5’)
Bungees 
Screws 
Bolts 
Drawer Slides (1.5’ long) 
Aluminum Straps 
Aluminum Strips (May not need)
Suction Cups 
Total Cost: $56
40
Convenience for Teachers





Drawer slides stop so the board does not slide too far
when carrying it
Easily Assembled with easy parts to work with
(PVC and Wood)
Able to shake with hand and with motor if available
Easy to use
Safe (Plus more safety tips in manual)
41
Three Part Manual
1.
2.
3.
How To Build It
1. Notes On Alternate Parts
How It Works
1. Notes On Convenience
Safety
1. Notes On Having It Around Children
42
Mounted Accelerometer
for Analysis
43
Goal

Leverage the input capabilities of the
microcontroller to increase potential to gather
more data about an experiments

Target multiple accelerometer inputs


Base platform
Structure
44
Protecting the Accelerometer
Shrink Wrap
SD Card holder
Pros
Cons
Transparent
Adds on weight to
the KNEX building
Strong protective
cover
Might prove to be
expensive
Accelerometer may
not fit firmly into
SD card holder due
to differences in
their dimensions.
Pros
Cons
Cheap
Careless shrink
wrapping may melt
the wires
Protects the
accelerometer and
the loose ends of the
wire as well.
Transparent
Long lasting
45
Mounting Accelerometer
Stick pads:
Pros
Cons
Sticks both sides
Has to be replaced
again and again
Easily removable
Short term use only
Holds up to 1 lb
Adheres to most
clean
Using a protection case with a hook
Pros
Cons
Can be quickly
mounted and
dismounted
Would add on some
weight on the
K’NEX building.
Protects the
accelerometer
Costs more than the
rubber band
Visible to the
children
46
Mounting Positions
Position 1
Position 2
Position 3
47
Final Conclusions



Short term: Stick pads and shrink wrap
Long term: Pocket-hook holder
Best mounting position – Position number 3
48
Thank You for Listening!
Questions?
49
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