SEMINAR ON 1)SCHEDULING2)KNOWLEDGE BASED SCHEDULING3)COMPUTER HIERARCHY CONTROL 4)SUPERVISORY CONTROL PRESENTED BY: AKSHAY WADALKAR ROLL NO. 02
SCHEDULING• Scheduling is an important tool or manufacturing and engineering, where it can have a major impact on the productivity of a process.• Scheduling relates to the timing of each individual delivery.• It mainly deals with handling application.• It increases efficiency of production.• Scheduling decreases material handling cost and waiting time for work in process.
SCHEDULING• It co-ordinate man, machine and production facility for obtaining higher output.• It uses graphical data plotted by taking readings to identify the errors in process• Corrective actions are taken and manufacturing lead time is minimized• Scheduling is the study of process and organizing them to obtain higher effficiency
Advantages of Scheduling• Process change-over reduction• Inventory reduction, leveling• Reduced scheduling effort• Increased production efficiency• Labor load leveling• Accurate delivery date quotes• Real time information
KNOWLEDGE BASED SCHEDULING• A general knowledge-based system consists of three components: – a database – a knowledge base – an inference engine
• The database stores declarative knowledge about the goals, the current situation of the world, and the semi finished plan.• The knowledge-base stores the domain-specific and procedural knowledge, often represented by production rules or operators.• the inference engine stores control knowledge indicating how to select operators and when to apply them.
KNOWLEDGE-BASED SCHEDULER CANPERFORM THE FOLLOWING TYPES OF SCHEDULING FUNCTIONS:1. Adaptive scheduling: Schedules are generated by goal-driven procedures; the scheduler can perform dynamic scheduling to adapt to changes in the FMS environment.2. Planning: State-space inference and heuristic search are used to derive production processes.
3. Optimizing: Simulation and selection of plans from alternates are done by evaluating performance criteria and heuristics.4. Learning: Recognition, refinement, encoding, and integration of processes are performed to enhance the scheduling performance.
COMPUTER HIERARCHY CONTROL• The term computer hierarchy control is used to describe such configuration which consist of following components. – Multiple process control station located throughout the plant to control the individual loop and device of the process.
– A certain control room equipped with the operator stations where supervisory control of plant occurs– All process and operator stations interact with each other by means of communication network.
SUPERVISORY CONTROL• The term supervisory control is usually associated with the process industries, but the concept applies equally well to discrete manufacturing automation.• Supervisory control represent a higher level of control than DDC, NC & PLCs.• Supervisory control denotes a control system that manage the activities of a number of integrated units operations to achieve certain economic objectives for the process.
• Supervisory control is not much more than regulatory control or feed forward control.• In other application the supervisory control system is designed to implement optimal or adaptive control.• Supervisory control can be defined as the control system that directs and co-ordinates the activities of several interacting pieces of equipment in manufacturing cell or system.
REFFERENCES• “AUTOMATION IN PRODUCTION SYSTEM” by Mikell P. Grover• “COMPUTER INTEGRATED MANUFACTURING” by N. Venkateshwaran• “Knowledge based Scheduling in FMS” by Michael J. Shaw.• http://production-scheduling.com/