Table of Contents


This manual explains how to use the Facilities Layout Applet/Application (FLAP) for achieving decent solutions to the Facilities Layout Probelm (FLP). NP-Complete and FLP theories are not discussed in depth and a decent understanding of both concepts are required before reading this manual. Also, prior knowledge of optimization or approximization heuristics is needed. For more information regarding such concepts please see the links section.


The FLAP is a program designed to facilitate the understanding and comparison of various sophisticated Facility Layout Problem (FLP) heuristics.

The FLP is a part of a well known family of problems called NP-Complete. The idea is to place fixed area departments in a facility of fixed dimensions. Generally, there are two ways to place these departments, either keeping their length and width dimensions intact or modifying their dimensions but keeping the area intact.

Using user-controlled animation, FLAP is a graphical gateway into the visualization of various FLP heuristics. The user has full control over the type of FLP problem to be solved, the data generated, the process of solving the problem at hand, and the visualization of the process.


The algorithms in FLAP are based on work by Simchi-Levi, and Donaghey & Pire. The row-fit layout technique is based on the "place and slide" algorithm in Simchi-Levi's "Facilities Layout and Planning" program. The banding technique is based on ideas first conceived in Donaghey & Pire's "BLOCPLAN" program. Also, the simulated annealing heuristic used in FLAP is based on the one found in Dr. Goldschmidt's "GRAAL".

FLAP was designed and implemented by Sidarth Khoshoo under the direction, and design of Professor Phil Kaminsky of the UC Berkeley Industrial Engineering and Operations Research department.


Facilities Layout Problem (FLP)
One of many NP-Complete problems that grow exponentially with each addition of a new item. The problem is simple, place fixed areas departments in a fixed size container to minimize the overall cost.

The container of the departments to be placed in a layout. Represents the "office space" or maximum area used to place the departments. In FLAP, this is the main screen under the menu bar. The facility bounds are the edges of this main screen. The facility's defined width and height are mapped to this blank screen.

Represents a fixed area of variable width and length (depending on the environment it is in). In FLAP, it is represented by a rectangle in the facility.

Department List
The list of departments used for the Facilities Layout Problem (FLP) heuristics and layout algorithms. The initial order of this list can be random.

The final placement of the departments in the facility using a layout heuristic.

The value of traveling from departments i to j. In FLAP, flows can be randomly generated or user specified. They may not necessarily be symmetric as in the random generation case.

Objective Function
This is the function used to determine a cost of a layout. The distance type used for the calculation can be configured to be either Euclidean or rectilinear.

The cost FLAP uses to gauge the various heuristics is the sum of the flow times the distance for all pairs of departments. The distance used can either be Euclidean or rectilinear between the centers of the departments in the virtual facility plane. The centers are the geometric center of the rectangular departments. They can be specified to be elsewhere within the department.

An algorithm that reaches a reasonable solution to optimizing the cost of a FLP layout. In FLAP, there are two types, FLP and layout. The FLP goal is to optimize the department list in terms of cost by choosing the optimal list order. Layout heuristics place the departments in order of the department list. The word heuristic and algorithm are used interchangeably in this manual.

A single run of a FLP heuristic on the facility.

Status Bar
Contains useful user messages concerning heuristics and graphical actions. Also prints the current cost during each trial.

Basic Use

The following are instructions to get a quick and easy start to FLAP:



Objective Function

The objective function determines the cost of a layout. The total cost is simply the sum of the flow between two departments times the distance between them. The distance can either be Euclidean or rectilinear. This can be configured by choosing "Objective Function..." from the Edit menu.

Layout Heuristics

The goal of the layout heuristics is to lay out the departments in the facility in the order of the department list. Different layout heuristics are applied to different types of FLP problems.

Layout Types

Department List Manipulation

At the crux of the FLP is to manipulate the list of departments to achieve an optimal cost.

Information Retrieval

The most readily available place for information about facility related actions is on the status bar underneath the facility screen. Check here frequently for messages about the results of various user actions or heuristics.

Mouse Manipulation

FLAP supports some basic mouse manipulation of the departments and layout. Sometimes a heuristic will not find a single feasible solution given specific facility data. Using one of the following can aid heuristics to finding a lower cost.

Java Related Issues

For more specific information about FLAP and Java, please see the FAQ


Back to the Facilities Layout Applet/Application

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