1 : Introduction

In this tutorial you will learn how to:

• Open an existing project or create a new one
• Create a precedence graph and introduce the data attached to each operation
• Create a first “logical-layout” (i.e.: representation of the line in terms of number of workstations and operations executed on each workstation)
• Manipulate the interactive balancing tools
• Run the Automatic balancing tool and visualize its results

2 : Management of the projects

    Once Optiline is launched, you discover a window entitled: “Editing Project: New Project” (Figure 2-1). The main window is divided in three tabs. The first tab "Operations" lets you define your product, the second one "Workstation" your line, and the third one displays the detailed schedule of all operators.

Figure 2-1

    Use the Save As option from the file menu to save your project. Set the file name to MyFirstProject.tsv.

3 : Defining the product

    The product we will study is the pen depicted in the following picture.

    The following table describes all operations required by the assembly and their durations.

    The first step to accomplish when you start the study of a new product with Optiline is to build its precedence graph. This graph will contain the following information:

• The name, code, duration of each operation
• The precedence constraints to be respected between the operations

    In order to explain a precedence graph creation, we will create the graph corresponding to the pen described in the previous section. We have 9 operations to define for this product. Click first on the “Operations” tab if you are not yet in the “Operations” environment.
 
    Let's create the first operation. To do this, click on the "Add One Operation" button.( )

    A blue rectangle as illustrated in the following picture will appear with the operation name written inside. On the bottom part of the window, there are several fields allowing you to modify the information attached to this operation.

Figure 4.1

    If you click anywhere outside the rectangle in the drawing zone, you will unselect the operation and these fields will be disabled. If you now click on the rectangle (the operation) “Name 1”, these fields will become editable again.
 
    Click now into the field “Name” and type “Insert the gray internal cylinder into the central cover” instead of “Name 1”. Then, select the “Time” field and type “400” instead of “100”. Click then on the “Apply” button to effectively enter that information into the system.
 
    Let us notice that, for this example, we have decided to work in hundredths of seconds, which means that a time of 400 represents 4 seconds. No units are pre-defined in the system but your units must respect the following properties :

• You can work with the units of your choice, as long as they are expressed with integer numbers
• All the times you define in the system will have to be expressed in the same units

    As the operation "Insert the white internal cylinder into the central cover" in the operation table defined above has to be executed after our first operation, a precedence constraint between the two operations has to be defined.

    To add the second operation, select the first one by clicking on it and then use the "Add One Successive Operation" button.()

    Your precedence graph should now looks like the following picture.

Figure 4.2

    The arrow joining the two operations means that the first one must be carried out before the second one. Like for the first operation, you must change the second operation properties by using the bottom of the window fields. Set the name to "Insert the white internal cylinder into the central cover" and the time to 400 and then click on the "Apply" button.

Figure 4.3

Let us now create the 7 remaining operations from our list in the operation tab. To do this click 7 times the "Add One Operation" button. ( )     Then move the operations by doing “drag and drop” operations and position them in a way similar to the figure on the left.     At this point, you should specify for each operation its name and duration according to the operation table defined before. To avoid this work, simply select the file "MyFirstProjectStep1.tsv" int the example submenu of the File menu.

 5 : Adding precedence constraints between operations

    Clicking on each operation lets you edit and inspect its properties.We will now add precedence constraints between all these operations. First we will create a Precedence constraint between the "Insert the white..." operation and the "Place the spring..." operation. For this purpose, we will right-click on the "Insert the white..." operation as depicted in the following figure.

Figure 5.1

    Select the "Add Successor" option. A yellow arrow will appear, move it to the "Place the spring..." operation and click the mouse button as shown in the following picture.

Figure 5.2

    Repeat the same steps to add a precedence between the "Insert the white..." operation and "Insert the main..." operation, to get the situation depicted in the following picture.

 
Figure 5.3

    To add multiple precedences in a row, you can select multiple operations as depicted in the following left picture, right-click on one of the selected operation and choose the "Add Successors" option. Two yellow arrows will appear as shown in the following right picture. Move your mouse to the "Place the central..." operation and click on it to finish the precedences.

    Add the required arrows to match the following figure.

Figure 5.6

You have certainly noted that the operation “Place the pin onto the top cover” has no arrow attaining it or leaving from it. This is because that operation can be executed at any moment and has not to precede or to be preceded by any other operation.      The precedence graph of the product is now finished. You can download the file corresponding to this step by selecting the file "MyFirstProjectStep2.tsv" in the example submenu of the File menu, or continue with your current project if your precedence graph matches the one on the left.

6 : Create a first layout of the line

    We are now ready to create a first layout of our line, by using the “Workstation” environment. For this, you have to click on the “Workstation” tab. The “Workstation” environment is divided into three parts:

• The top right part of the window contains the representation of the entire line
• The left part contains the detailed description of a workstation
• The bottom-right part contains the list of operations, with their attached information

    To create a workstation simply click on the add one workstation button in the middle right part of the window.( )

    A new workstation will appear as a vertical green bar in the top right part of the window as shown in the following picture. Like for the operation, just click on the workstation (in the top right area of the window) to edit its properties in the bottom of the window fields.

 
Figure 6.1

    Select the workstation and set the Cycle Time to 1800 and its Max Peak Time to 2000. Click on the "Apply Button".

    Create 2 additional stations with the the add one workstation button in the middle right part of the window.( )

    Select now the first operation in the list by clicking on it. Click then on the first workstation to select it (it will be highlighted), and click on the  button "Assign operation to a workstation" button. ()

    This will have as effect to add the selected operation to the workstation 1 as shown in the following picture. The first column of that operation is now green, meaning that it has been placed into a workstation. You will thus have a first complete layout when the whole list is green.

 
Figure 6.2

    It is also important to note that when you select an operation in the list, one or several green arrows are painted above some workstations. Only the workstation having that green arrow on their top can accept the selected operation (This means that putting the operation on the workstation does not violate precedence constraints,types,links,e.t.c.).

Select all operations in the list and assign them to one of three workstations. You should end up with a line similar to the one on the right.

Figure 6.3

7 : Interactive Balancing

Now that you have your first layout of the line, you can use OptiLine to do an interactive balancing by directly dragging operations from workstation to workstation to try to find a better solution.     When you drag an operation onto a forbidden workstation, a red cross will appear on the operation. Simply release the operation on the chosen workstation to change the operation assignement. You will also see in the workstation detail view the position of the operation in the precedence graph.     You can now try to move operations in this line in order to find a better solution than your current one. In this case, it is probably still possible to find a better solution in a reasonable time because of the small size of the data. But this manual work can be painful on a bigger line and you will have to use OptiLine automatic optimization algorithm.

Figure 7.1

8 : Automatic Balancing

Now that you have tried to find a better solution interactively, let’s try it automatically. To do this, click on the "Optimize" button. ()     The dialog box shown on the right will appear. Depending on your licence, you will have to use or not a distant server for computation. If your are using a distant server, you will have to follow these instructions.When the optimization is finished, you will get the automatically balanced line in a new project window.     You can download the automatically balanced line corresponding to this step by selecting the file "MyFirstProjectFinished.tsv" in the example submenu of the File menu

Figure 8.1

9 : What's next ?

• You can learn how to use product variants by reading the next tutorial
• You can read a page about the general use of the software here
• You can learn about the different operation parameters in this help section
• You can learn about the different workstation parameters in this help section