Initial Exercises—IFS/Constraint Based Scheduling

Initial Exercises

Purpose: The instructor uses these exercises to demonstrate the basic functionality of IFS/Constraint Based Scheduling (CBS), which includes:

• Creating and scheduling a shop order.

• Viewing a shop order in the Simulation Client.

• Using the Scheduling Client to change the shop-order schedule.

• Reporting shop orders.

Scheduling a Shop Order

Purpose: The purpose of this exercise is to show you how to create a shop order for CBS to schedule.

Windows:
Shop Order
Parameters for Distribution and Manufacturing

Steps: To complete this exercise, perform the following steps.

1. Make sure that the program is set to create shop orders with the Planned status.

Note: You can specify that shop orders be created with the Planned status on the Parameters for Distribution and Manufacturing.

2. Create a new record.
3. In the Order No field, enter SO1.
4. In the Part No field, enter 250-G10.
5. In the Site field, enter your site name, if it is not defined as the default site for your user.
6. In the Sched Direction list, click Backwards Scheduling.
7. In the Earliest Start Date field, enter next Monday's date in MM/DD/YY format.
8. In the Need Date field, enter next Thursday's date in MM/DD/YY format.
9. In the Lot Size field, enter 10.
10. Save the shop order.

Expected Results: Once you save a shop order, CBS schedules it and updates the start and finish dates. CBS tries to fit the shop order into the current schedule. It checks the availability of both materials and resources to determine the earliest date and time the shop order can start. The Need Date is the date before which the order should be completed. With backward scheduling, CBS tries to adjust the schedule of the shop order so that it is as close to this date as possible. If the order is not finished by the day before its need date, a message appears indicating that the shop order did not meet its need date, and the order is designated as tardy in CBS.

Viewing a Shop Order in the Simulation Client

Purpose: The purpose of this exercise is to demonstrate how you can view results and perform schedule changes without affecting the Scheduling Server. An image of the Scheduling Server data is created for simulation purposes. This enables the server to continue processing transactions. All changes made in simulation are not applied to the Scheduling Server or database. They must be applied manually in the database to take effect in the Scheduling Server.

Windows:
Simulation Client

Steps: To complete this exercise, perform the following steps.

Note: Once the Simulation Client appears, click Plot Settings in the Gantt Overview pane and then click This Gantt Chart. Click Plot Settings in the same menu to open the Settings window. In the Plot Settings tab, verify that no plot settings have been selected.

1. In the Tree View/Activities window, double-click Activities, and then double-click Shop Orders to see a list of the shop orders that are now in the Scheduling Server.
1. Select shop order SO1. While holding down the left mouse button and the Shift key, drag the shop order to the object table area of the Gantt Overview pane (the white space on the left side of the chart). The shop order is now plotted on the Gantt chart. In the object table, the shop order appears as three objects: the parent shop order, SO1, and its children, Operations SO1-10 and SO1-20.
2. If the shop order does not appear on the Gantt chart, click a few times on the scroll arrow adjoining the End Date field above the Gantt chart to expand the time schedule. Try the other buttons above the chart, and experiment with their functions.

Note: In the object table, the status or statuses of each object are displayed. Also, each object (e.g., a shop order or shop order operation) has its own icon, which helps to identify the type of object. To remove an object from the Gantt chart, select it and click Drag and Drop Remove from List or drag the object itself to this button, or click Clear All to remove all objects. Note that this action does not delete the objects entirely. It only removes them from the chart.

To obtain a detailed view of an object, such as a shop order for example, select it in the object table area of the Gantt Overview pane. The details of this object are displayed in the Gantt Detail pane. The Details tab displays the constituents of the selected object and zooms the timescale to the period in which the selected object has been scheduled. The Resources tab displays the work centers and work center resources associated with the selected object. The Materials tab displays any finitely available material that is associated with the selected object. The following table describes the information presented for each type of object when it is selected in the Gantt Overview pane. In the case of scheduling scenarios, such as the Tardy Shop Order scenario, you can select its object in the object table area of the Gantt Overview pane to view charts and detailed information about the scenario in the Gantt Detail pane.

2. Another way to adjust the time schedule is to drag an object, i.e., a shop order, upward from the object table onto the Drag & Drop Auto Timescale (ruler) button to adjust the time scale and make this object's schedule completely visible. You can also achieve this result by select the object and then clicking Drag & Drop Auto Timescale.
3. In the Tree View/Master Data window, double-click Master Data, and then double-click Work Centers. For Work Center 400, hold down the left mouse button and Shift key, and drag the work center into the object table area. The work center and its resources appear as objects in the Gantt chart. Also plot Work Center 500.
4. Make sure that the shop orders and work centers are visible in the Gantt chart. Click Plot Settings in the Gantt Chart window and then click Plot Settings in the menu that appears. The Settings window appears.
5. In the Settings/Plot Settings/General tab, select the Resource Availability check box. The gray color for work center resources represents the time during which the resource is unavailable, according to the work center's calendar.
6. In the Show area of the Settings/Plot Settings/Operations tab, select the Names check box to plot the operation names on the operation and work center resource objects.
7. Select the Splitted check box. Now the operations are plotted as connected segments of time during the available time rather than as a block of time covering both available and unavailable time.
8. Select the Planned Line and Released Operations Line check boxes. Now the status of the operations in the Gantt chart is shown with color codes (Planned = light green).
9. Select the Setup Times check box. Now the operation time is broken into its setup portion (white with blue diagonal lines) and run-time portion (gray with a light green stripe to indicate the status).
10. Select the Tardy Line check box.
1. Find your shop order, SO1, in the Gantt chart.
2. Right-click Operation 20.
3. Hold down the right mouse button, and drag the operation to the right, into in the next available time slot. The shop order operation becomes tardy, and a red stripe appears in the operation. Remember that you are in simulation mode, so no changes can be saved to the database.

Using the Scheduling Client to Change the Shop Order Schedule

Purpose: The purpose of this exercise is to show you how to adjust the schedule, view the results, and save changes to both the Scheduling Server and the database. An image of the Scheduling Server is made to perform schedule adjustments. However, the server is locked to prevent users from processing transactions. All changes made in the Scheduling Client can be applied automatically to the Scheduling Server and database. Unlike the Simulation Client, a limited number of options for schedule changes is available, i.e., only schedule prioritization, not capacity adjustments.

Windows:
Scheduling Client
Shop Order

Steps: To complete this exercise, perform the following steps.

Note: The Scheduling Client locks the Scheduling Server so that you cannot make changes that affect the schedule. If other users try to make schedule updates on the same site (e.g., updating shop order dates, updating shop order operations, or making capacity adjustments), a message appears indicating who is locking the Scheduling Server. The default time limit for the lock is 10 minutes. Once this limit is reached, the Scheduling Client automatically releases the lock on the Scheduling Server. You can change this time limit.

1. Plot Shop Order SO1.
1. Right-click Operation 20, and drag it to the right so that it finishes the next day. The operation becomes tardy, as indicated by the red stripe.
2. You can do the following:
• First Operation: Move back to the earliest start date defined for the shop order, or move forward to finish no later than the start of the second operation (except when operations are parallel).
• Middle Operations: Move an operation to an earlier start time (it cannot start before the finish time of the prior operation), or move forward to finish no later than the start of the next operation (except when operations are parallel).
• Last Operation: Move an operation so that it finishes at a later time.

Note: You can move an operation only to a point in time at which all its required resources are available. CBS checks this condition as you move the cursor.

2. Save the new schedule to the database, and release the server. Exit the Scheduling Client.
3. Query Shop Order SO1 to verify that the finish date has changed.
4. Open the Shop Order window, and click the Operation tab. Check the start and finish date/time of Operation.
5. Optionally, reset the shop order to the previous schedule.
1. Right-click the shop order header, and then click Schedule Shop Order.
2. CBS reschedules the shop order based on the original criteria (e.g., the finish date returns back to its original value).

Reporting Shop Orders

Purpose: The purpose of this exercise is to show you how the data for shop floor execution interacts with CBS.

Windows:
Shop Order
Scheduling Client

Steps: To complete this exercise, perform the following steps.

Note: Before beginning this exercise, make sure that the shop order has been released and then reserved with all material issued. Also, make sure that the Auto Close option is selected for the shop order. If Auto Close is not selected, each shop order must be closed manually after it is received.

1. In the shop order header, right-click and then click Report. Report each operation on the shop order as complete. Save the changes.
2. Open or refresh the Simulation Client.
3. Plot the shop order on the Gantt chart. Note that the status of the shop order operations has changed to Reported.
4. Return to the Shop Order window. In the shop order header, right-click, point to Material Actions, and then click Receive. Receive the entire quantity for the shop order. The status of the shop order changes to Closed.
5. Open or refresh the Simulation Client. The shop order has been removed from the Scheduling Server.