关于AGV 系统的体系结构建模

Automated Guided Vehicle System (AGV)

1.Problem Description

An AGV System has the following characteristics:

A computer-based AGV can move along a track in the factory in a clockwise direction, and start and stop at factory stations. The AGV has the following characteristics:

1) A motor, which is commanded to Start Moving and Stop Moving. The motor sends Started and Stopped responses.

2) An arrival sensor to detect when the AGV has arrived at a station, e.g., arrived at station x. If this is the destination station, the AGV should stop. If it is not the destination station, the A GV should continue moving past the station.

3) A robot arm for loading and unloading a part onto and off of the A GV.

The A GV system receives Move commands from an external Supervisory System. It sends vehicle Acknowledgements (Acks) to the Supervisory System indicating that is has started moving, passed a station, or stopped at a station. The AGV system also sends vehicle status to an external Display System every 30 seconds.

It is given that the arrival sensor is an event-driven input device and that the motor and arm are passive I/O devices. It is also given that the AGV system communicates with the Supervisory System and Display System by means of messages.

https://www.360docs.net/doc/f817935810.html,e Case Modeling

Figure 1 Use Case

From the problem description, it can be determined that there are two use cases, one dealing with the vehicle moving to a station and the second dealing with sending vehicle status to the display system. There are four actors: Supervisory System, Display System, A rrival Sensor, and Clock. From the perspective of the AGV System, the Supervisory System and Display System are external system actors. The Arrival Sensor is an input device actor, whereas the Clock is a timer actor.

3.Conceptual Static Modeling

It depicts a system of systems, consisting of the Supervisory System, the A GV System, and the Display System. The A GV System is modeled as a composite class, which receives commands from and sends acknowledgments to the Supervisory System, and sends status to the Display System. The AGV System is composed of four classes: the Arrival Sensor, the Motor, the Robot Arm, and the Clock.

4.Assignments

a)Describe each use case in detail as we do in class;

b)Draw software static context modeling diagram;

c)Give the class and object structuring of AGV;

d)Draw Communication Diagram for each use case using classes shown in Figure 1. Draw the integrated Communication Diagram based on the results of

A)Dscribe the use case

1）

Use case name :Move to station

Summary: The vehicle moving to a station by taking the command of the Supervisory System and send acknowledge to the it

Actor:Supervisory System（primary）Arrival Sensor(secondary)

Preconditions:The vehicle is moveable

Main sequence:

1. The Supervisory System send the commands to the AVG system .

2. The AVG system recieve it and move the vehicle as the command

3. The Arrival Sensor recieve the events of the movement and send it to The Supervisory System

4.The Supervisory System updates the command

Alternative sequences:

Step 3:No events the system do nothing

Postcondition: Move to a station

2）

Use case name : Send vehicle status.

Summary: The AGV system sends vehicle status to an external Display System every 30 seconds Actor: Clock（primary）Display System(secondary)

Preconditions: The AGV System is on wroking

Main sequence:

1.When time is right . The Clock send a request to The AVG SYSTEM for posting the vehicle status

2. The AVG SYSTEM responsed it and send the data to the display system

Alternative sequences:

Step 1: If it is not the right time ,do nothing

Postcondition: The vehicle status are sent to the Display system

B)Draw software static context modeling diagram;

C) Give the class and object structuring of AGV;

1. Move to Station

2.Sends Vehicle Status

E)Draw the integrated Communication Diagram based on the results of d).