Document5

Disaster Advances Vol. 8 (3) March (2015)

35

Modeling and simulation of ship lock based on secondary development Liang Gui-lan

1,2*, E Yu-kun

1,2 and Feng Liang

3

1. Key Laboratory of Coastal Disaster and Defence, Ministry of Education, Hohai University, Nanjing 210098, CHINA

2. College of Harbor, Coastal and Offshore Engineering, Hohai University, Nanjing 210098, CHINA

3. College of Civil and Transportation Engineering, Hohai University, Nanjing 210098, CHINA

*[email protected]

Abstract With the purpose of solving the problem of

insufficiency of parametric design of the whole lock

and simulation effect, this paper has developed a

program based on Solidworks with Visual Basic to

realize parametric design of lock model and

simulation of the lock. On the basis of analysis of lock

structure, the program has realized parametric design

of upper lock head, lower lock head and lock chamber

by controlling the key sizes of the lock structure and it

has reduced repeated works and has improved the

efficiency. Take an engineering project as example to

examine the result of the program and it matches the

objectives well. This program has provided a

convenient means to analyze the calculation results

and to preview the model. Keywords: Lock, solidworks, secondary development, parametric design, visualization.

Introduction The ship lock is a kind of channel buildings and is made to

overcome the water head difference which can improve the

navigation conditions. Its basic structure includes lock

chamber, upper lock head, lower lock head and approach

channel and some other parts1. A lock is complicated,

especially in upper and lower lock heads because of the

variation of water transmission way and stilling facilities.

As a result, the designers should perform very well in the

profession and in space imagination. Formerly people

receive drawings as achievements which do better in

introducing the details but do less well in understanding

than 3D models, especially lock head. To some degree it

has added the repeated works when designers communicate

with others and modify the drawings2.

People use 3-dimensional CAD technologies such as

AutoCAD to build ship lock construction. The method

makes it easy to check the results and also shows the details

in a direct way. Nowadays a large number of softwares are

utilized in the aspects of force and stability analysis,

sometimes ignore and simplify the structure details. It is

well known that the lock head is much more complicated

than the lock chamber, so in the past people have only

studied the system of lock head and how to realize

parametric design. There is a lack of study in modeling of

the whole body of a ship lock. Meanwhile, many models

are not capable of simulating operating process. These

problems are in existence in lock modeling.

Based on solidworks, secondary development method is

used with Visual Basic to make the program come true.

The results are easy to check and contain the animation that

can simulate the change of water levels and location of the

gates. In consideration of large quantities of locks, the

program regard miter gate as study object and water

transmission way is centralized water transmission system,

only build the shape of lock without checking the stability.

The empty tank in the lock head has not been considered.

Lock modeling method Lock modeling analysis: The lock transports ships by

concentrated water head, which consists of lock head, lock

chamber, approach channel and corresponding

equipments3. They are complex and various. The lock head

separate lock chamber and approach channel so the lock

chamber could maintain the water level inside. Water

inflows and discharges via water transmission way. Lock

chamber is a place where ships wait, it has integral

structure and separate structure two kinds.

The program is aimed at building 3-D model of lock

realistically. In order to reduce inessential works, to

develop the program in the future readily, one kind of lock

structure has been chosen as an example to analyze the

matter. Upper lock head and lower lock head are both

equiped with miter gate, water transmission way is

centralized water transmission system and lock chamber

adopts integral structure. According to engineering

experience, some parts are default.

Solidworks secondary development and Visual Basic:

Solidworks is 3-D design software based on Windows,

values parametric design and feather most which can build

complex bodies conveniently. solidworks applies Feather

Manager which simplifies the details of a model, thus

makes it popular4. Besides, solidworks also provides plug-

in tools such as Motion Manager, Photoworks and so on.

But in certain industry, it is necessary to meet specific

needs, to make repeated works standard and automated, so

secondary development based on solidworks is of vital

importance. API functions within solidworks containing

most instructions in solidworks can be called by advanced

language like Visual Basic.


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The program chooses Visual Basic as secondary

development language to exploit solidworks. Visual Basic

can develop a visualized program with the advantages of

easy to use, widely used and efficiency. It can be combined

with other advanced language such as C++, Java5. Visual

Basic adopts event-driving programming and interactive

developing, it is easy to learn and use and can find practical

and concise human-computer interaction interface.

Program developing progress: To call methods and

attributes of solidworks API by Visual Basic, objects are

needed. Objects contain SolidWorks, Environment, Frame,

Attribute Def, Modeler and others. Each level has its own

objects and each object has its own attributes, methods and

events6. Before creating solidworks applied object, the

software and VB must be connected.

Dim swApp As Object

Set swApp = CreateObject("sldworks.application")

Code above can open solidworks interface and then API

can be called.

In this program lock modeling module is completed in

solidworks parts environment. Before operation it has to

compile parts environment and open a new solidworks

project. Below is the code.

Set Part = swApp.NewDocument("C:\Documents and

Settings\All Users\Application

Data\SolidWorks\SolidWorks 2010\templates\part.prtdot",

0, 0, 0)

swApp.ActivateDoc2 "part1", False, longstatus

Set Part = swApp.ActiveDoc

The simulation module is completed in assembly

environment. First insert models of lock chamber, lock

heads and gates saved already, then connect lock chamber

with lock heads steadily with the function of cooperation, but the gates can move in a limited space which makes it

possible to simulate working process according to the

location of gates and water level inside and outside the

lock. The code of inserting a part and open a solidworks

assembly project is as follows:

Set Part = swApp.OpenDoc6("E:\lock model and

simulation\model data\lock chamber.SLDPRT", 1, 0, "",

longstatus, longwarnings)

swApp.ActivateDoc2 "lock chamber", False, longstatus


Set Part = swApp.NewDocument("C:\Documents and

Settings\All Users\Application

Data\SolidWorks\SolidWorks

2010\templates\assembly.asmdot", 0, 0, 0)

swApp.ActivateDoc2 "assembly1", False, longstatus


Considering the lock structure with the requirements and

confine of the program, to make the interface clear and

brief, the program consists of lock chamber, upper lock

head and its gate, lower lock head and its gate and

simulation 4 modules7.

Take integral structure for instance to build lock chamber

3-D model, the designing sizes include length, width,

height (breast included), floor thickness, side wall width; in

consideration of the breast wall, the height and width of the

breast wall should be determined. The model is shown as

figure 1.

Figure 1: Lock chamber model

The module of upper lock head and its gate contains two

parts, namely upper lock and miter gate modeling. Miter

gate is simplified. The upper lock head can be divided into

floor, side pier and water transmission way 3 parts, the

users can type in the numbers of each size according to the

describing words in front of the input box. Some parameter

unspecified, such as baffle wall style, the program just has

default settings according to traditional examples. The

parametric design interface is shown as figure 2.

The module of lower lock head and its gate is similar with

the module of upper lock head and its gate, the code and

interface can be inferred. Simulation module consists of

lock preview and simulation two parts. Left part of the

interface realizes preview function. The water transmission

way inside lock head is hollow; this part provides a means

to browse it. Click export button to export lock head already saved. For example, as the model of lower lock

head built according to an engineering construction is

exported, click|left view option, top view option and front view option to observe orthographic views, meanwhile the model has become linear body, click hypostatic model option to resume. Input distance from profile to the bottom of the floor in the input box, click profile of water transmission way, then it forms a profile at the exact location.


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Figure 2: Parametric design interface of upper lock head

Figure 3: Lock preview interface

Figure 4: Profile of water transmission way of lower lock head


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The right part of the interface of simulation module

performs in assembly environment with the condition that

all documents saved in the certain folder. Click lock preview, the whole lock is created automatically. The lock chamber and lock heads are still but the gates can move and

the water levels inside and outside the lock chamber can

change.

Visualization and simulation of the lock With the help of plug-in tool Photoworks users can render

the model and make well qualified and simulated picture;

users can also make movies with Motion Manager Tool by

changing water levels and angles of gate and flow. This

paper has examined the results of the program by an

engineering example. First build the lock chamber model.

The controlling sizes are listed in table 1. Operate the

program and click model button to gain the model.

While modeling the lock heads, the gate is created as well

but is saved as a single part which has nothing to do with

the lock head, aiming at moving the gate to realize the

simulation of lock operation. The sizes of upper lock head

have been shown in figure 1. The upper and lower lock

heads rendered models are as in figure 5.

Simulation module must operate only after all the models

have been saved, otherwise the model cannot be created

when the part needed cannot be found. The model of water

is fictitious body which has a high transparency. The parts

of fictitious water model are built in assembly environment

and then will be saved in the same folder as other parts.

Based on existing information, when the gates are open and

when closed, how long it lasts to change the water level

inside the lock chamber, these can all be gained. In Motino

Manager Environment, the users can change the angle of

the gates and the water flow to simulate lock operation and

output short movies. As making the animation, the

background can be changed; the models material, color, transparency and the light vary, so it is not rational to

exploit this aspect.

Table 1

Designing sizes of lock chamber

(a) (b)

Fig. 5: 3D models of lock heads (a) upper lock head model (b) lower lock head model

Places in

lock

chamber

Main sizes of lock chamber Floor

thickness

Side wall

width

Breast wall

Effective

length

Sedation

segment

Height Width Height Width

Sizes(m) 230.00 20.00 15.00 2.00 2.00 23.00 1.20 0.30


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Fig. 6: Details of rendered lock model

Fig. 7: 3-D model of the whole lock

Conclusion Ship lock is a common building in water conservancy and

plays a key role in water transportation. Based on

solidworks, this paper has developed a program that can

provide assistance for designers with Visual Basic to realize

parametric design and simulation of the lock. The interface

is clear and easy to modify, it has given a possible solution

to such kind of study. The operation result of the program

has proved to be reliable, but it cannot solve all problems as

the types of locks change. Furthermore, it requires high

capability of utilizing the software solidworks and its plug-

in tools. In detail, then the gates are not miter gates or the

water transmission ways change its type, the program can

be no longer applied. While simulating the operation of the lock, ship element has not been considered yet which can

be improved in the future.

Acknowledgement This paper is supported by project of the nature-science

fund of Jiangsu Province (Project BK2011743), the

Peoples Republic of China.

References 1. Liu Xiao-ping and Tao Gui-lan, Canalization Project,

Beijing, Peoples Transportation Press (2009)

2. Lei Fei et al, 3D design of lock head based on AutoCAD

ARX, Port & Water Engineering, 2, 128-132 (2013)

3. Xiao-kang H.E. et al, Modeling of the Lower Lock Head of

Ship Lock Based on AutoCAD and VB, Journal of

Heilongjiang Hydraulic Engineering College, 34(4), 126-128

(2007)


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4. Zhang Xiang-yue, 3-Dimension modeling for offshore

platform by second development of Solid Works with VB

Language, Tianjin, Tianjin University (2006)

5. Niu You-qi and Sun Jian-guo, New Edition Visual Basic

Program Design Courses, Suzhou, Suzhou University Press

(2007)

6. Jiang Hong et al, Solidworks Secondary Development

Examples Analysis, Beijing, Mechanics Industry Press (2004)

7. Tang X. J. and Su C., Development of CAD Software for

Ship Lock Design, Port & Water Engineering, 4, 73-76

(2006)

8. Chen Wen-long, Study on Visual and Integrating CAD

Systems of the Miter Gate Dissertation for Master Degree of

Science, Nanjing, Hohai University (2003).

(Received 15th December 2014, accepted 30

th January

2015)