where    ∈  × is the mooring line configuration matrixandNisthenumber of mooringlines。Thenitcanbedefined as

experiment results are to be shown。 For this, the experimental set-up is illustrated in Fig。 3, and the schematicdiagramforexperimentalisshownin Fig。 4。 As illustrated in the figures, the control

system (NICompactRio)isplacedonthevessel andworksbyitself。

However,thevesselmotionsare captured by the CCD camera which isattachedonthecelling。 Theimagedataobtainedbycameraistransferred to host onshore computer, and vessel motions are calculatedbyusingvectorcodecorrelation technique in realtime6~7)。Thenthecalculated position and heading angle are sent to a real time controlsystemCompactRioplacedonthe vessel。

Fig。 3Photooftheexperimentsystem setup Also, the information including vesselmotions

andallsensingsignalsaretransferredto the

mass (Balancing Weight in Fig。 4) are suspended betweenthetwoendpointsofcabletoillustrate the passive control property of PM system which provides the restoring, damping and mean control forcestocompensatetheloadvariationdueto wind, wave and current。 Here, the weightofeach massis0。2[kg]。

Fig。4Schematicdiagram ofexperimental set-up

3。2experimentresults

Theinertiaanddampingmatricesofbargeship,

 and,arecalculatedbyhydrodynamic softwarepackageandexperiment as:

⎡20。2[kg] 0 0 ⎤

monitoring system (Host Computer) bywireless

M ⎢

0 28。2[kg]0。5[kg  m2 ]⎥ ,

⎢ ⎥

network。Theprocessandtechniqueforexperiment

⎣⎢ 0 0。5[kg] 3。0[kg  m2 ]⎥⎦

(8)

are precisely illustrated in Fig。 4 and Fig。5 as described in previous。 Where, thevesselcomprises the barge ship and mooring lines。Especially,the bargeshiphasamassm=18。5[kg],length, L=1。3[m] and breath, B=0。4[m]。 And 4mooring

D diag{1。6[kg/s],8。0[kg/s], 1。2[kg。m2 /s]}。

Themooringlinesconfigurationaredescribedas

(x1, y1 ) (0。65,0。2), (x2 , y2 ) (0。65,0。2),

linesareproperlyinterconnectedbetween the vesselthroughsailwinchesandthewallof basin。

(x3 , y3 ) (0。65, 0。2), (x4 , y4 ) (0。65, 0。2)。

(9)

Also,theload-cellstomeasurethecabletension are placed on the cable。 Where the submerged

The PID controller usedinthisstudy has followingstructure:

The integral term is used to eliminate the steady-state error between the desired position and actualpositionofvessel。  and areprovided as:

illustrates when the hard disturbance condition is considered,thegoodperformance of ship cannot bemaintained。Inthiscase,theship is continuouslyoscillatedfor long time。 In contract to the non-activated control given in Fig。 5, good control performancecanbepreservedfromnormal to hard disturbance condition in the caseofPID control as shown in Fig。 6。 Thewinchessystem change the tension of mooring linestomakethe bargeshipreturntoinitialpositionafteraffection ofenvironmentalloads。Thecomparisonbetween the commanded tension and actual tension of each mooring line isshowninFig。7。Withcontrolling the winch by pulling and releasing each line, the tension of mooring line can follow the commanded tension made from controller。 In the PID case, the smootherchangeofcommandedtensionis shown。

4。Conclusion

Inthispaper,asthefirsttries,theauthors build