Page 233 - Sensors and Control Systems in Manufacturing

Networking of Sensors and Contr ol Systems in Manufacturing
to details of the equipment’s operation in an error-free environment. 193
Relationships must be developed between the physical description of
the equipment’s operation and the functional parameters that will be
associated with this operation. The objective is to link together the
physical design of the equipment and its functional performance
through sensory and control systems in the factory setting.
This concept provides insight into an area in which future manu-
facturing system improvements would be advantageous, and also
suggests the magnitude of the cost-benefit payoffs that might be asso-
ciated with various equipment designs. It also reveals the operational
efficiency of such systems.
An understanding of the relationships between the equipment
characteristics and the performance parameters based on sensors and
control systems can be used to select the best equipment for the
parameter requirements associated with a given factory configura-
tion. In this way, the manufacturing design team can survey alterna-
tive types of available equipment and select the units most appropri-
ate for each potential configuration.

4.2 The Number of Products in a Flexible System
The first parameter listed earlier, the number of product categories
for which the manufacturing system can be used, represents the key
concern in flexible manufacturing. A unit of automated manufactur-
ing equipment is described in terms of the number of product cate-
gories for which it can be used with only a software download to
distinguish among product types. A completely fixed automated
manufacturing system that cannot respond to computer control
might be able to accommodate only one product category without a
manual setup. On the other hand, a very flexible manufacturing sys-
tem would be able to accommodate a wide range of product catego-
ries with the aid of effective sensors and control systems. This param-
eter will thus be defined by the breadth of the processes that can be
performed by an automated manufacturing equipment unit and the
ability of the unit to respond to external control data to shift among
these operations.
The most effective solution will depend on the factory configura-
tion that is of interest. Thus, OEMs are always concerned with antici-
pating future types of factories in order to ensure that their equip-
ment will be an optimum match to the intended configuration. This
also will ensure that the concept of error-free manufacturing can be imple-
mented with a high degree of spontaneity. A continual tradeoff exists
between flexibility and cost. In general, more flexible and “smarter”
manufacturing equipment will cost more. Therefore, the objective in
a particular setting will be to achieve just the required amount of flex-
ibility, without any extra capability built into the equipment unit.