Networked CollaborativePseudo Dynamic Testing

Platform

KJWang, SJWang, YSYang, CWHsu, KCTsai, CHLoh

The 6th National Conference on Structural Engineering, 2002/08/28, Kenting

Outline• Purpose – Virtual Laboratory• Demands• Program Demonstration• Platform Architecture (PNSE)• Networked Structural Experiment Protocol

(NSEP )• Typical Interaction• Efficiency• Experiment Validation• Conclusion & Future Study

Purpose – Virtual Laboratory

Lab #1 Lab #2

Virtual LabNumericalIntegration

Internet

Guest

Demand on larger, more complex, more realistic specimen

Software / hardware corporationCost effectiveWorldwide instant participation

Demands

• Environment independentDifferent controllers: FTiim, 458, 407 controllersDifferent languages: C++, VB, Labview, MatlabDifferent OS: Windows, Linux, UNIX, DOSDifferent hardware.

• Event reflective• Easy incorporation• Efficient transmission• Data security• Friendly individual participation

Program Demonstration

Platform Architecture (PNSE)

TCP/IP

Network Structural Experiment Protocol (NSEP)

Internet

<Server>System

administrator

<Client type I>Structural analysis

<Client type II>Facility control

application

<Client type III>Registered researcher

<Client type IV>Unregistered

guest

-Server---System administrator-Multi-client design-Signals & information transmission-Active event dispatch

-Client type I---Structural analysis-Numerical integration-Command generation (Global)-Receiving relevant signals from labs-Viewing processed / row data-Instant discussion (dual-direction dialog)

-Client type II---Facility control application-Command execution-Receiving actuator commands-Sending relevant measured signals (Local)-Viewing processed and / or row data-Instant discussion (dual-direction dialog)

-Client type III---Registered researcher-Viewing processed and / or row data-Storing processed and / or row data-Instant discussion (dual-direction dialog)

-Client type IV---Unregistered guest-Viewing processed data-Instant discussion (dual-direction dialog)

Internet Access: TCP/IP by Socket• TCP/IP: Transmission Contr

ol Portocol / Internet Protocol. To connect different networks.

• Sockets: a package of subroutines providing access to TCP/IP on most systems, widely supported by different vendors.

• Platform independent: OS, hardware, and programming language.

Windows DOS

UNIX Linux

Internet

Control System

407 Controller

458 Controller

FTiim Controller

NSEP (Networked Structural Experiment Protocol)

• SD_MESSAGE• SD_LOGIN• SD_STRUCTINFO• SD_PRJINFO• SD_PEERINFO• SD_STRUCTDISP• SD_STRUCTFORCE• SD_PRJSTATE• SD_CLNSTATE• SD_DISCUSS• SD_SIGNAL

Notify the remote host a specific message

LENGTH+TYPE+MSG • SM_ERR• SM_QUERY_PJ• SM_QUERY_PS• SM_QUERY_CS• SM_QUERY_ST• SM_QUERY_PEER• SM_NO_LOGIN• SM_NO_PRVLG• SM_STRUCT_ERR

Length Type Data

2 bytes 1 byte n bytes

Send data or message related to login procedure

LENGTH+TYPE+MSG+PARAM

• LG_REQUEST• LG_SUBMIT• LG_PASSWRONG• LG_GRANT• LG_DENY• LG_UNKNOWN• LG_REPEAT

Transmit the structural information LENGTH+TYPE+DATA

• NDOF• M• C• K• D0• V0• A0• DT• DURA• QUAKE

Transmit the project information LENGTH+TYPE+DATA

• PRJNAME• SY • SM• SD• SH• Sm• Ss

• EY• EM• ED• EH• Em• Es• STATE

Notify each client the information of all participants

LENGTH+TYPE+DATA • NPEER• PEERID • PEERACCESS• LOGINOK• RUNSTATE

Transmit the displacement command

LENGTH+TYPE+DATA • CURRENT • DISP

Transmit the measured restoring force LENGTH+TYPE+DATA

• CURRENT • FORCE

Notify the running state of the project

LENGTH+TYPE+STATE • PS_UNKNOWN • PS_NOTREADY• PS_READY• PS_RUNNING• PS_HOLDING• PS_INTERRUPTED • PS_FINISHED

Notify the running state of the lab

LENGTH+TYPE+STATE • CS_UNKNOWN • CS_NOTREADY• CS_READY• CS_RUNNING• CS_HOLDING• CS_INTERRUPTED • CS_STOPPED

Send the instant dicussion text string

LENGTH+TYPE+MSG • PERSON• TEXT

Send registered signal (headers or data)

LENGTH+TYPE+DATA • CLNTNAME• TIME• NSIGNAL• VALUE

Typical Interaction

ControlProgram

PNSEServer

SD_LOGIN LG_REQUEST

SD_LOGIN LG_SUBMIT(NCREE/NCREE)

SD_LOGIN LG_GRANT

SD_MESSAGESM_QUERY_ST

SD_STRUCTINFO

SD_MESSAGESM_QUERY_PEER

SD_MESSAGE, SM_QUERY_CS

SD_CLNSTATE(NCREE, CS_READY)

SD_PRJSTATE, PS_READY

SD_CLNSTATE(NCREE, CS_RUNNING)

SD_STRUCTDISP, 0.00 sec

SD_STRUCTFORCE, 0.00 secSD_SIGNAL, 0.00 sec

SD_SIGNAL, 0.00 secSD_PEERINFO

Efficiency

Site-computer Elapsed time (s)

733-256-Ncree 0.97

600-128-Ncree 1.1

266-256-Ncree 1.7

200-128-WuGu 70

One-site test Two-site testSite#1 Site#2 Elapsed time (s)

733-256-Ncree 733-256-Ncree 1.4

733-256-Ncree 600-128-Ncree 1.4

733-256-Ncree 266-256-Ncree 2.0

733-256-Ncree 200-128-WuGu 93, 86

600-128-Ncree 600-128-Ncree 1.3

600-128-Ncree 266-256-Ncree 1.6

600-128-Ncree 200-128-WuGu 93

266-256-Ncree 266-256-Ncree 2.3

266-256-Ncree 200-128-WuGu 224, 83

200-128-WuGu 200-128-WuGu 102.153

733-256-Ncree 600-128-Denvill, NJ. 1299, 1949

733-256-Ncree 1000-128-WestCoast 952

Duration : 20 sect : 0.02 secSteps: 1000

Stress Test1000000 iterationElapsed: 00:18:13 1.093 msec / step

：Displacement Transducer

：Dial-gauge

：Strain Gauge

：Strain Rosette

：LVDT&Load cell

：Temposonic III

Layout of Measuring Device

Experiment Validation• SDOF system• M = 760 Ton, = 1%, t = 0.02 s, Duration = 30 s• 1999 Chi-Chi, Tcu-075 0.05g

Experiment Validation – Results

• 41:03• UCSD (server)• NCREE (Analysis)• NCREE (Control)

-15

0

15

0 10 20 30Time (sec)

Dis

pla

cem

ent

(mm

)

-1200

-600

0

600

1200

-12 -6 0 6 12

Displacement (mm)

Fo

rce

(k

N)

Conclusion & Future study• Primitive implementation of the concept VL has

been achieved by the proposed platform PNSE and the protocol NSEP. They made corporative pseudo dynamic testing feasible.

• PNSE could be augmented to access to data base.• Architecture of NSEP could be more simplified,

but the content could be more augmented.• Methods of bulk data transmission should be

thoroughly studied and implemented.• Socket efficiency.• Dynamic WWW web pages should be

implemented.