Automotive Tutorial

Transcription

Automotive Tutorial

ProBalance Automotive Tutorial
ProBalance 1.6
Mixed Model Automotive Line Balance Tutorial
Copyright 2006, Proplanner
1/19
2/19
Tutorial Objective:
This tutorial will show you how to create a Mixed Model Two-sided balance for
an automotive assembly line, using each of the two balancing algorithms –
Weighted Average and Peak Model.
Please use the sample scenario file Auto.xml (located in the Help Directory of
your CD, or available on the Proplanner website) for this tutorial.
Step 1. Open a Scenario
Open the sample scenario file (Auto.xml) supplied with the installation. Use
menu “File => Open Scenario” to open. You can also use the tool bar to open
The data will be loaded as shown in the following image.
Each row of the data represents a task in the assembly line. For each task,
there are several attributes (“ID”, “Description”, “Type”, “Process Time”, … )
associated to a task as shown in each column.
The properties of the scenario can be accessed in the menu
“File=>Properties”.
3/19
The “Scenario Properties” window will be shown as the following image.
Please note that the “Line Side” property of this scenario is “Two Sided”, and
the “Line Type” property of this scenario is “Mixed Model”.
Close the “Scenario Properties” and return to the main window. Notice that the
main window has three tabs at the left bottom, as shown in the following.
z
z
z
4/19
Task Sheet: the window of the list of tasks and their attributes
Precedence Graph: the window for defining the precedence graph of
the tasks
Task Grouping: the window for defining task groups
Step 2. Editing the Task Data
Click the “Task Sheet” tab, we can edit the data for each task in the window.
For a complete description of the columns of the task sheet, please reference
the ProBalance on-line help, or the PDF formatted manual located on your
installation CD or on the Proplanner website.
For this tutorial, please consider the following columns:
z ID: the ID of the task
z Description: the description of the task
z Process Time: the manual process time of the task
z Walk Time: the walk time involved in the task
z Machine Time: the machine process time of the task
z Freq.: frequency of the manual and machine process
z Occ.: occurrence of the task
z Net Time: the net time is not editable. The value of the net time will be
automatically calculated using the following formula:
Net Time = [(Process Time + Machine Time)*Freq. + Walk Time]* Occ.
z
z
z
z
The “Net Time” is the time that is actually used in the calculating the
balance.
“Line Side”: the line side of the task needs be to performed at.
- “E”: Either side of the line
- “L”: The left side of the line
- “R”: The right side of the line
Models: the models that the task is applied to. See “Step 3. Define
Model and Options” below.
Options: the options that the task is applied to. See “Step 3. Define
Model and Options” below.
Work Location: the location on the vehicle that the task is performed,
e.g., 2L represents the front left side of the vehicle. This column (as
well as the column “Remarks” and “Element Data”) is not used by
ProBalance, but could be imported into Proplanner Workplace Planner
5/19
to facilitate processing the task. See Workplace Planner for details.
z
Step 3. Define Models and Options
Click “View => Model Editor”, the main window will change to the Model Editor
window, as shown in the following image.
Notice that there are two tabs in the window: “Model Sheet” for defining models
and “Option Sheet” for defining options.
Models refer to different product model. For example, an automobile
manufacturer could have models of 4-cylinder car, 6-cylinder car, etc. Options
refer to the features that can be added on some or any models. For example,
Air Conditioning and CD player are two options that can be added onto all
models.
In this tutorial, we define 7 models for the automobiles. Demand% is the
percentage of the model that is scheduled to enter the assembly line. Notice
that the Demand% should add up to 1. The “Display Color” is the color that
is used for representing the model in the line balance chart (see below).
The following image is the “Option Sheet”. We defined 5 options here. The
Penetration% is the percentage of the all products that has the option. Notice
that the Penetration% needs not to add up to 1.
6/19
After defining the models and options, we can specify in the “task sheet” which
tasks are ONLY applied to what models and options. See “Step 2. Editing the
task data”. Those tasks that do not specify the “Models” or “Options” are
assumed to be performed on all products.
Click menu “View=>Task Editor” to go back to task sheet. Specify the models
and options for the tasks.
7/19
Step 4. Define Stations
Click “View => Station Editor”, the main window will change to the Station
Editor window, as shown in the following image. We defined 6 stations here,
namely, 73L, 73R, 74L, 74R, 75L, 75R. The “Line Side” column specifies at
which line side the station is located. Notice that if you don’t define the stations
yourself, the Line Balance will automatically generate the stations needed,
named in the format of “New 1”, “New 2”, etc.
Step 5. Define Precedence Graph
Go to the “Precedence Graph” and change the precedence graph. Each node
represents a task in the “Task Sheet”.
To move a node, simply drag and drop the node.
To add an arc, move the mouse pointer around the center of the task from
which you want to draw the arc (the cursor will be changed to a “hand” shape),
left click and drag the arc to the task to which you want to connect to.
To delete an arc, click on the arc and select delete on your keyboard.
Save the precedence diagram. The diagram will be redrawn optimally.
8/19
Special Note: a useful technique in defining the precedence graph is the
dummy node, as illustrated below.
First, we add a dummy operation (“dummy01”) at the end of the list in the
“Task Sheet”, with “Process Time”, “Walk Time”, and “Machine Time” all equal
to 0. Save the scenario, it will automatically calculate the “Net Time” to be 0.
Go to “Precedence Graph”, you can see a new bubble as “dummy01”. In the
following small precedence graph, dummy01 serves as a connector between
two groups (2601 and 2602 as the first group; 2603, 2604 and 2605 as the
second group). The precedence graph here specifies that any node in the
second group cannot start until all the nodes in the first group have been
finished.
9/19
Step 6. Line Balancing
Click menu “View=>Balancing Station View”, as shown in the following image.
Click menu “Balance => Auto Balancing…”, the “Default Assignment” dialog
window will show up.
Input as the above image shows. Click “OK” button. We here use the “Balance
Type” of “Minimize number of station”, and the “Select Algorithm” of “Weighted
Average” which uses weighted average of all models for balancing. For a
complete discussion of the “Balance Type” and “Select Algorithm”, please
reference the on-line help.
The resulting line balance will show, as in the following image.
10/19
Notice that the TAKT time is represented by a red horizontal line. There are 5
stations (73L(L), 73R(R), 74L(L), 74R(R), 75R(R)) used. For each station,
there are 8 bars, representing the load of the 7 models defined and the load of
the average of all models considering the demand% of each model. Also
notice that the average bars are always below the TAKT line.
In the lower half of the window, you can watch the details of each station. In
“Select Station”, select the station that you want to look into. It will list all the
tasks that are assigned to this station. Also notice that the “Line Side” column
of each is consistent the station’s line side.
Lets now try a different line balance method.
If you select “Minimize number of station”, “Peak Model Balance”, we get the
following. Notice that the peak bars of all stations are below the TAKT time
line, which is the reason for “Peak Model Balance”.
11/19
Use “Minimize TAKT Time” and “Weighted Average” with 4 desired stations, to
get the following task assignments. Notice that in this method, we needed to
specify the number of stations, since we are trying minimize TAKT time given
the limited station resource.
The following is the result of using “Minimize TAKT Time” and “Peak Model
Balance” select algorithm.
12/19
13/19
Notice how the “Balance Type” and “Select Algorithm” affect the balancing
results.
Step 7. Manual Adjustment
For some reason, you may want to adjust the assignment of some tasks to
some specific stations. To do that, right click a task, and a menu will show up,
as in the following image.
14/19
In the above image, we are trying to change assignment of task ID. 2596. Click
“”Change Assignment…” menu. The following window will show up.
Choose “73L” and then Click “OK” button. The task ID. 2596 is then assigned
to the station 73L. Choose “73L” from the “Select Station” List Box to verify, as
shown in the following image.
Notice that there is a “P■” in the “Violations”, which means that the assignment
of the task No.2596 to Station 73L violates the task precedence as specified in
the Precedence Graph.
15/19
Move cursor over the small red square, the details of the violation will show up.
This tells that the task No. 2593, No. 2594 and No. 2595 should precede the
task No. 2596. When doing manual adjustment, ProBalance only gives a
violation warning; therefore it is the user’s responsibility to make sure no
precedence is violated.
There are three columns in the “Violations”, representing the violation of
precedence, of a monumental resource and of resource respectively. See
“Step 8. Use Resource in Line Balance” about the violations of resources.
Step 8. Use Resource in Line Balance
Some tasks may need some specific resource to perform. Click
“View=>Resource Editor” to edit the resource. In the following image, we
define two resources, AutoMachine01 which is a monumental and KTD
Machine.
“Monumental” resources are the resources that are fixed or are monuments.
These are resources that cannot be moved from their positions like a fixture, a
hoist etc.
16/19
For a Monumental resource, we need to specify at which station the resource
is located. Click “View=>Station Editor” to define, as shown in the following
image.
Then go to “View=>Task Editor” to define which task needs what resource.
Those tasks that do not specify any resource are assumed to be performed
without any specific resource.
17/19
Then go to line balancing, you can specify whether or not to consider the
Monumental Resource Constraints.
ProBalance will always first consider the precedence of the tasks and make
sure that there is no violation of the precedence. After that, ProBalance will
consider the monumental resource constraints. However, it is possible that
the monumental resource constraints could not be met and a warning is given
in the “Violation” column. For example, there is only one monumental resource
and it has to be used by the first and the last task in the precedence graph. It is
very possible that there is a violation of the monumental resource, since the
only way to avoid the violation is to put all the tasks in one station which has
the monumental resource. In such cases, further investigation is needed by the
user, as well as manual adjustment of the assignment.
An image of the violation of monumental resource
ProBalance does not consider a common Resource constraint when doing line
balancing. A “Resource Violation” warning is given only to show that the
resource is needed at this station for this task.
An image of the violation of resource
Step 9. Line Balance Reports
After line balancing, there will be two reports generated in the software:
“Balance Report” and “Station Summary Report”. Click menu “Report=>” to
select one of them.
Balance Report
18/19
19/19
Station Summary Report
Congratulations!! You have now completed the first tutorial on using the
ProBalance. You can now start to try your own line balancing scenario for your
study. For more information, please refer to ProBalance Help file.
Special Note: After do the line balancing, the ProBalance application will
generate an XML-based Scenario file that can be input directly into the
Proplanner Workplace Planner. The Workplace Planner will then automatically
determine and diagram each operators walk patterns within each station of the
moving-vehicle assembly line. For more information about Workplace Planner,
please refer to Workplace Planner Tutorials and Help files.

Automotive Tutorial

Transcription

Similar documents

ELUCID Decision Support System and Field

RHS AND CRYROP - Redlands High School

Handy Wallet Guide

Mobiletron - moocreations

GNYADA Sales Academy - Greater New York Automobile Dealers

Presented to WRIC TV 8 Richmond, VA

BuggyBag - BurdaStyle.com

Yahoo! Yellow Pages - Halifax Community College

Stuttgart, Germany June 7

Learn how to make your own .svg files and cut