Manufacturing system
Definition of manufacturing
system
1.
A manufacturing system can be defined as the
arrangement and operation of machines, tools,
material, people and information to produce a
value-added physical, informational or service
product
whose
success
and
cost
is
characterized by measurable parameters.
2.
A manufacturing system is an approach to
making products that is based upon several
factors. These include how much of the product
is needed, how quickly the product must be
produced and how unique the product must be
to ensure sufficient sales. Manufacturing systems
include custom, assembly, flexible, intermittent,
reconfigurable,
just-in-time
and
lean
manufacturing systems.
Decision hierarchy of industrial information system
Level 5: Distribution
Level 4: Plant
Level 3: Factory
Floor
Level 2: Work
cell/ Production
line
Level 1:
Machine
Transportation planning
Supply chain inventory
control
Demand forecasting
Order processing
Purchasing
Aggregate production
planning
Accounting
Materials management
Maintenance management
Shop floor scheduling
Quality management
ERP
MES
Inspection/ SPC
Materials handling
Part sequencing
CNC machine tools
Robots
Programmable controllers
CONTROL
S
1.
The machine control level is responsible for ensuring that the sequence
of machine operations corresponds to the planned sequence necessary to
fabricate the part. Typically, the sequence of operations is carried out as
prescribed by the program resident in the machine controller, and there
are few, if any, decisions to be made.
2.
the production line or work cell level, the objective is to supervise the
interactions between a group of related machines or processes. This level
of decision making is not concerned with the operation of the machine or
process. The emphasis here is on the release and delivery of materials to a
machine in the work cell at the correct time.
3.
the factory floor level, decisions are made that affect groups of
production lines or work cells. For example, several production lines or
work cells may be serviced by the same materials management system
that requests the movement of raw materials from storage to production
so that they can be manufactured into a finished product.
4. the plant level, decisions are less concerned with the daily operation of the
factory and are more closely related to the business planning objectives of the
fi rm. A typical plant-level production control decision is aggregate production
planning, which refers to the process of planning the use of the plant’s
production capacity to meet customer demands over a period of months or a
year. The output of this plan is a master schedule of what products will be
produced during each period of time going forward over the planning horizon
of the plan.
5. the distribution system level the emphasis is on coordinating the supply of
finished product to the end customer. Maintaining appropriate and costeffective inventory levels, as well as managing the transportation of product
between warehouse locations in the supply chain, is a problem addressed at
this level.
Coordinating the layers of
ERP
the system
Forecasting
Production planning Inventory control
Costing
Purchasing
Recipe
management
Transportation Supply chain management
What was
produce
d
Operation scheduling
Production dispatching
Work in process status
management
Data acquisition
Real time
actual
results
IoT
MES
What to
produc
e
Lot traceability CCs
Quality control
HiCs
Maintenance
Control Layer
Process set point control
monitoring
Machine tool control
Senso Controll
r
er
HeC
s
Process
Cell control
How to
manufactur
e

ERP: Enterprise resource planning (ERP) is business management
software—usually a suite of integrated applications—that a company can
use to collect, store, manage and interpret data from many business
activities, ERP provides an integrated view of core business processes,
often in real-time, using common databases maintained by a database
management system. ERP systems track business resources—cash, raw
materials, production capacity—and the status of business commitments:
orders, purchase orders, and payroll.

MES:
Manufacturing
Execution
Systems
(MES)
are computerized systems used in manufacturing. MES can provide the
right information at the right time and show the manufacturing decision
maker "how the current conditions on the plant floor can be optimized to
improve production output." MES work in real time to enable the control of
multiple elements of the production process (e.g. inputs, personnel,
machines and support services).
Manufacturing Execution
System

MRP/MRP II/ERP are generally thought of as “planning” systems.
They are responsible for supporting the planning of production, but
they are not very well integrated into the execution of production.
This void in available software solutions on the shop floor has led to
the development of the manufacturing execution system (MES). The
MES is an attempt to manage resources, including materials,
machines, and personnel, on a daily or even hourly basis. Typical
MES functions include the following:

Dispatching and monitoring production

Detailed scheduling associated with specific production units in
order to meet specific performance criteria.

Data collection from factory floor operation to provide a history of
factory events.

Quality data analysis

Product history recording
Computer integrated Manufacturing

Computer-integrated manufacturing (CIM) is
the manufacturing approach of using computers to
control the entire production process. This integration
allows individual processes to exchange information
with each other and initiate actions. Through the
integration of computers, manufacturing can be faster
and less error-prone, although the main advantage is
the ability to create automated manufacturing
processes. Typically CIM relies on closed-loop control
processes, based on real-time input from sensors. It is
also known as flexible design and manufacturing
CIM
http://www.technologystudent.com/r
mprplmth.1namtni/07
NETWORK ARCHITECTURE

The network architecture is a description of how the various layers of the
decision hierarchy will communicate with one another. The network
architecture is typically implemented with the use of local area networks. A
local area network (LAN) is a communication network that is implemented
over a limited area and is usually owned by one organization. It is a
common medium that allows several computers or several machine
controllers to be connected, and, as long as each computer uses the protocol
convention of the LAN, communication can take place at high data rates.

Figure 1.4 shows a typical example for a modern industrial company. This
architecture shows three distinct layers. At the bottom, the physical
processes of manufacturing on the shop floor are arranged in stations along
a production line or in manufacturing cells. Controllers that are dedicated to
those physical processes control the operations at each station. These
controllers may be computers, but they are more likely special-purpose
computers, called programmable logic controllers (PLC), which have been
specifi cally designed to control and collect formation from machinery.

Historically, manufacturers of machine controllers have implemented
communication requirements using local area networks designed specifically for
their own controllers. In Figure, we are assuming that the controllers have the
capability of communicating with each other over a common local area network,
sometimes called a shop floor data highway. Such communication capability allows
individual machines to “talk” to one another as peers. This is known as “peer topeer” communication capability. So, for example, if a machine at one station has a
failure, the controller at that station can transmit that information to other stations
or to the supervisory controller, which may respond by stopping the processes and
signaling for assistance.

Another distinct layer of the architecture is the business layer, at which functional
departments are connected to one another via computers and a local area network.
The factory host computer is the repository of data for factory operation. The
individual functions shown are the high-level business and planning functions of
the factory. In Figure, these functions are interconnected Figure Typical network
architecture. 8 Introduction with each other and the factory database over their own
local area network. The distinction between the shop floor LAN and the businesslevel LAN is one that has developed in practice over time because of differences in
the communication performance requirements at each level as well as available
LAN options on the factory floor.
Manufacturing Control - Managing and controlling the physical activities in
the factory aiming to execute the manufacturing plans. Normally, a
manufacturing control comprises the short-term process plan and the shop
floor activities.
Three indicators for testing a manufacturing execution system

Agility - Capability to react in a short period of time to the occurrence of
unexpected disturbances (i.e. production environment changes).

Flexibility - Capability to adapt to new, different or changing
environments. In manufacturing world, several flexibility classifications are
presented in literature, like mix, changeover, volume, product and
sequencing.

Re-configurability - Ability to support different manufacturing system
configurations, i.e. different production systems scenarios, with a small
customization task.
Traditional Manufacturing
execution Approaches
Centralized Control Structures

is characterized by a single decision node, where all the planning and processing
information functions are concentrated.

Advantage: a
optimization

Disadvantage: low, speed of response, control
complexity, tolerance to faults and expandability,
specially for large systems.
better
management
and
control
Hierarchical Control
Structures
Hierarchical Control
Structures

In the hierarchical architecture, a complex problem is
decomposed in several simpler and smaller problems, and
distributed among multiple control layers. This architecture is
characterized by the existence of some control levels,
distributed in a tree structure, allowing the distribution of
decision-making among these hierarchical levels. The relations
between hierarchical levels are based on the master-slave
concept.

Advantage: The main advantages of this architecture are the
robustness, the predictability and the efficiency that are
better than in centralized architectures.

Disadvantage: the appearance of disturbances in the system
reduces significantly its performance.
Heterarchical Control
Structures

The heterarchical architecture, also designated by
autonomous agent approach in the agent domain, is
characterized by the high level of autonomy and cooperation, being the client-server structure with fixed
relations no more applied.

Advantage: allow a high performance against
disturbances, The expandability of the system is an
easier task, because it is enough to modify only the
functioning of some modules or add new modules to
the control system.

Disadvantage: is a novel technology, needs more
research works, at the time the implementation of this
control structure is not common
What is agent

An agent is a computer system that is
capable of independent ( autonomous)
action on behalf of its user or owner
(figuring out what needs to be done to
satisfy design objectives, rather than
constantly being told).
An example: Spacecraft
Control

When a space probe makes its long flight
from Earth to the outer planets, aground
crew is usually required to continually
track its progress, and decide how to deal
with unexpected eventualities. This is
costly and,
robot soccer team

A team of robotic soccer players play a game
against another robotic soccer team

Robots should cooperate with teammates, but
should compete with adversaries to win the
game
https://www.youtube.com/wat
ch?v=YI9xnZ9msn8
The main characteristics of these agents are

Autonomy, because agents should be able to perform most of
their tasks without the direct intervention of humans and
should have a degree of control over their own actions and
their own internal state.

Social ability, because agents should be able to interact with
other software agents and humans

Responsiveness, agents should perceive their environment and
respond in a timely fashion to changes occurring there

Pro activeness, agents do not simply act in response to their
environment, they are able to exhibit goal-directed behavior by
taking the initiative."

Adaptability, meaning that the agent should be able to modify
its behavior over time in response to changing environmental
conditions and to an enhanced knowledge about its problemsolving role

Mobility, because the agent should possess the ability to
change its physical location to improve its problem-solving
capacity

Rationality, because an agent should be expected to act in
order to achieve its goals and not to prevent its goals from
being achieved without good cause

Nwana gave yet another perspective on the agent paradigm.
The main characteristics an agent should exhibit have been
identified in a set of three attributes:
autonomy, cooperation, and learning.
Multi agent system

A multi agent system is a system in which a number
of agents interact with each other.

In the most general case, agents will be acting on
behalf of users with different goals and motivations.
To successfully interact, they will require the ability
to cooperate, coordinate, and negotiate with each
other, much as people do.
Agent Models
1.
Basic model of an agent
2.
Reactive agents
3.
Deliberative agent
4.
Hybrid agent
5.
...
6.
…
Multi Agent System Design
Methodologies
1.
Extensions of Knowledge-Oriented
Methodologies
2.
Extensions of Object-Oriented and
Manufacturing Methodologies
3.
Role-Based Methodologies
4.
System-Oriented Methodologies
5.
Interaction-Oriented Methodologies
6.
Behavior-Oriented Methodologies
Extensions of Knowledge-Oriented
Methodologies
The knowledge-oriented methodologies proposed for
designing agent based systems are mostly extensions of
the knowledge engineering methodology CommonKADS
(Schreiber et al. 1994). These methodologies adopt the
CommonKADS approach and add agent-oriented
concepts to it. There are two examples of knowledgeoriented methodologies for agent based systems,
CoMoMAS and MAS-CommonKADS.
Extensions of Object-Oriented and
Manufacturing Methodologies
 Burmeister
(1996) extends the object
oriented methodologies to
agent
oriented analysis by introducing
mental and co-operation concepts. As
in object-oriented analysis, she
proposes three models which can be
developed in parallel:
1.
The agent model contains agents and their internal
structure, described in terms of mental notions such
as goals, plans and beliefs or similar concepts.
2.
The organizational model specifies the relationships
among agents and agent types. Organizational
relationships can be inheritance or role based as in
real organizations.
3.
The co-operation model describes the interaction
(or more specifically the co-operation) among
agents.
Example PROSA

Van Brussel et al. (1999) propose a methodology for identifying
manufacturing agents based on the object-oriented approach and
the PROSA framework. The PROSA framework consists of
product, resource and order agents, which may be supported by
staff agents. These agents can be aggregated or specialized in the
object-oriented sense in order to create a taxonomy of agents for
a specific manufacturing application.
Step by step
1.
Identification of the agents and their responsibilities in the
specific manufacturing application.
2.
The identification process is guided by the PROSA framework
and starts with an object-oriented model of the manufacturing
system.
3.
The designer then selects the objects in this model which should
become agents, even though the methodology does not provide
any criteria for identifying suitable objects.
4.
The agents are classified in the PROSA framework by
aggregating and specializing agents.
Case study: workflow
management system
1.
Management agent: A management agent provides
the user interface for the human workflow manager. It
can:
– Create and delete role definitions and process definitions
– Instantiate a new process instance
– Create resource agents for new resources
– Simulate the execution of a process.
2. Storage agent: A storage agent manages the persistent
data, for instance the definitions of tasks, roles and
processes, and the monitored data. It also notifies all
management agents if the data has changed
3. Process agent: A process agent is responsible for the
execution of one particular case
4. Resource agent: A resource agent is the user interface
for the human resource or the interface for some tool
which can do tasks automatically (such as printers and
scanners). Every resource has its own resource agent.
5. Resource broker agent: A resource broker is responsible
for the resource management. Every resource agent is
registered with at least one of the resource brokers and a
process agent requests the resource broker to identify and
allocate a suitable resource.
6. Monitor agent: A monitor agent gathers the data in the
system that is necessary to analyze workflows, such as
execution times and resource utilization.
7. Control agent: A control agent) provides the feedback
mechanism required for process re-engineering. The
control agent continuously senses the anomalies or
violations of the criteria specified by the manager and
sends warning messages to the manager agent and also
logs those messages.
Simple example

To illustrate the functionality of the system, we chose a simple
process of ordering a book. After the customer orders a book, the
inventory has to be checked whether a copy of this book is there and
the credit rating of the customer has to be checked. These checks are
done in parallel to speed up the process and afterwards the results are
evaluated. Based on the evaluation it is decided whether the order
can be processed or should be rejected. Assuming that the processing
of the request has been approved, the shipping of the book and the
sending of the bill are done in parallel. Finally the results of shipping
and billing activities are archived so that one can handle possible
customer complaints.
The sequence diagram for starting a new work
case
The sequence diagram for allocating a resource
and executing a task
Home Work
MAS production control system for manufacturing umbrellas
For more information: An RF-ID driven holonic control scheme for
production control systems
A Short Description of Umbrellas

a large piece of cloth with a single RFID tag is colored in the
dyeing process, and then it is transported to the cutting process,
where it is sliced into pieces and where an RFID tag is attached to
each piece of cloth. All of the tags of cut cloth receive the lifetime
information from the original cloth's tag but are assigned a
sequential sub-ID under the same component ID. Wire props, each
with one RFID tag and a piece of cloth with a matching RFID tag,
are processed into the final umbrella product during the wire prop
attachment process, which is a joined process. Although the final
product still has two attached RFID tags, only one of them, marked
as “representative” is used in later stages.

RFID tag readers/writers are attached to the front
and rear of production facilities to read RFID tags
attached to the components. The process ID read
from the tag is used to instruct conveyors to deliver
the corresponding component to the desired
process.

When each process is completed, the RFID tag
reader/writer in the rear side updates the current
status in the tag. If the order changes, the RFID tag
reader/writer in the front side modifies the status in
the tag to indicate a cancellation or increase or
decrease in the number of products.