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In the flexible inter processing scenario different types of items are moved from one place to another
depending of production specific requirements. The requirements can specify one-of-a kind, small quantity
or large quantity of items to be moved. A temporary/partial or complete item is placed alone or together
with other items for either further manufacturing or temporary storage. An item is undergoing a series
of manufacturing activities and must be stored, retrieved and moved between such activities.
In this
scenario the flexible inter processing system knows which items are involved and the planned manufacturing
activities for such items. The units of the inter processing system, for example a combination of autonomous
guided vehicles (AGVs), various forms of stationary storage and temporary manufacturing tools interact
and collaborate about timing and responsibility for the actual flow of the inter processing movements
of items. The units of the flexible inter processing system will communicate either with the surroundings
of the manufacturing processes to locate the items or directly with the items themselves. Flexibility
and autonomy are essential properties of the inter processing system in the sense that the units collaborate
about the actual activities and units can change dynamically from actual but unnecessary services to other
services with high priority.
Information concerning the status and priority of each item is available and can be controlled through
interaction with the flexible inter processing system at any time.
In order to reach the needed flexibility
and a reasonable capacity, a large amount of control units will be placed in production equipment, AGV’s
etc., and to make this economical feasible the units must be low price. A key issue is therefore to make
the architecture for the distributed control units as simple as possible, only handling the needed processes
and communication, in a generic way so that different kind of equipment can be controlled by the same
control system. The project will develop and produce cheap AGV’s, possible from scrap plastic, as
well as cost effective control systems and architectures, with focus on minimizing the processor and communication
demand in the distributed units.
To start experiments at an early stage and at low cost, experimental test platforms will be set up.
An experimental prototype, based on LEGO Mindstorms artifacts equipped with processing and communication
capabilities combined with additional PDA devices and wireless communication will be set up. In the initial
configuration, PDA’s are attached to the LEGO artifact and serve as an informational element of
the tangible object whereas the LEGO construction itself represents a physical element. The PDA communicates
with the LEGO construction through an IR port and controls the various sensors and actuators from the
LEGO Mindstorm package. LEGO constructions may be stationary or movable. Their functionality may include
to move parts of itself or to move itself.
The result of this phase will be a prototype of flexible inter processing consisting of:
- Intelligent containers, movable by LEGO Mindstorms.
- Simulated intelligent production sites, with available LEGO bricks.
- LEGO Mindstorms, used as flexible transportation units.
- A simple high-level shop floor control system, enabling users to input tasks etc.
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