ISEE Part IIThe Application Protocol Approach
K.J. Wang, S.J. Wang, W.C. Cheng, Y.S. Yang, K.C. TsaiNational Center for Research on Earthquake Engineering
Joint NCREE/JRC WorkshopInternational Collaboration on Earthquake Disaster Mitigation Research
October 18, 2003
Outline• Demands• Platform for Networked Structural
Experiments (PNSE)• Networked Structural Experiment Protocol
(NSEP)• Experimental Validation• Networked Pseudo Dynamic Tests on 3-story
CFT/BRB Frame• Conclusions
Demands
• Environment independent - Different facility controllers, control programs, OS, computer hardware
• Event reflective - Change of running state:
READY, RUNNING, HOLDING, INTERRUPTED_TEMP, INTERRUPTED, FINISHED
- Lab events: specimen adjustment, control problems, … etc. (worthy recorded) - Human conversation (not worthy recorded)
• Efficient transmission
• Data security
• Friendly individual participation
PNSE (Platform for Networked Structural Experiments)
ServerCGMDB
server
Viewer
PNSE
CameraFCM #1 FCM #2
CGM: Command Generation ModuleFCM: Facility Control Module
NSEP data packets
based on TCP/IP
commandsresponses
Video server
Webserver
NSEP (Networked Structural Experiment Protocol)
• SD_ERROR• SD_LOGIN• SD_PRJINFO• SD_SIGNALINF
O• SD_PRJSTATE• SD_CLNSTATE• SD_CPSCMD• SD_IDVCMD• SD_IDVRSP• SD_CPSRSP• SD_SIGNAL• SD_DISCUSS
Length Type Data
2 bytes 1 byte n bytes
Packet composition
Server Client
packet
packet
• Command cycle - SD_CPSCMD, SD_IDVCMD - SD_IDVRSP, SD_CPSRSP - SD_SIGNAL
• Active notification (Event trigger) - To save networked resources - To enhance overall efficiency - To accommodate more complex interactions in the future
Experimental Validation
NCREE Lab NTU Lab
6.0 m2.
37 m C1 C2
X
Y
X
Y
concrete infilled
double tube• 3 Tests - Test A: Domestic - Test B: Transnational (CGM at Stanford) - Test C: Transnational (Server at Stanford)
• Test results: displacement historiesTest C, NTU, Y dir, TCU 082, PGA=9.13gal, M=235.6ton, =2%
-6
-3
0
3
6
0 5 10 15 20Time (sec)
Dis
p.
(mm
)
Analysis Test S F
C
F
F
F
C S
F
FC SA
B
C
(US)
(TW)
(TW)
(US)
(TW)
Experimental Validation (cont.)
85%
10% 1%3%
0%
1%6%
1%
1%21%
0%
71% 58%
16%
16%1%
4%
5%
S FC
F
F
FC SF
FC S Test A (domestic) Test B (CGM Stanford) Test C (server Stanford)
Internet (CGM ⇔ Server)
Internet (FCM ⇔ Server)
Server works
CGM works
FCM works (actuator control)
FCM works (miscellaneous)
Communication Program Test A Test B Test C
CGM ⇔ ServerPNSE 0.000
8 0.1661 0.1693
Ping <0.01 0.1628 0.1653
NTU ⇔ ServerPNSE 0.003
7 0.0056 0.1651
Ping <0.01 <0.01 0.1625
NCREE ⇔ ServerPNSE 0.004
6 0.0039 0.1701
Ping <0.01 <0.01 0.1608
Experimental Validation (cont.)
Test C (Time consumed in network)
0
0.4
0.8
1.2
0 200 400 600 800 1000Step
Tim
e (s
ec)
Time consumed in internet between Analysis and Server per stepTime consumed in internet between Server and Facility Control in NTU per stepTime consumed in internet between Server and Facility Control in NCREE per step
• Time consumed in data transferring over the Internet is quite stable
PDT on 3-story CFT/BRB Frame
FCM, Windows XP
CGM, FreeBSD
PNSE server, Windows XP
Database serverMS SQL ServerWindows 2003
Web serverWindows 2003
Web guest
Web guest
Web guest
Conclusions• All data including command and lab feedback
can be transmitted correctly on PNSE.
• Efficiency of PNSE is satisfactory. Less than 0.1701 seconds is needed for a packet to make a round trip between Taiwan and Stanford.
• Running states of the whole project and of all PNSE clients can be reflected accurately and promptly on PNSE.
• The proposed PNSE and NSEP has preliminarily achieved the goal of networked collaborative experiments.
PDT on 3-story CFT/BRB Frame
i step 0 1 2Scan no.
1 2 3
THS
FCM
Server+
CGMSend initial condition to
FCM
Actuator control
Trigger (i=1)
Trigger (i=2)
Get scanned data (i=0)
Get scan data (i=1)
Send calculated
responses to FCM
Send calculated
responses to FCM
Sleep
Send scanned data to server
(i=0)
Ramp
Send force to server
Write to DatabaseScan Scan
Send scanned data to server
(i=1)
Sleep
Send force to server
Top Related