1. Fuzzy Logic Anti-Sway Controllerfor Container Crane Control Mail: zameer@bcs.org.uk

2. Crane controller

3. 1. Problem in brief • When a container is picked up and the crane head starts to move, the container begins to sway. • While sway is no problem During transportation, a swaying container can’t be released.

4. Objective • A container ship has to be loaded and unloaded in a minimum amount of time for cost reasons.

5. 2. Control Model Alternatives • Conventional PID control : Control task is inherantly non-linear • Mathematical Model-based control : weight of the container is unknown. Crane motor behaviour is not linear Cable involve elasticity. Wind disturbances can’t be included.

6. 3. A linguistic control strategy

7. 4. Implementing a linguistic Control Strategy 1.IF Distance = far AND Angle = zero THEN Power = pos_medium 2a.IF Distance = far AND Angle = neg_small THEN Power =pos_big 2b.IF Distance = far AND Angle = neg_big THEN Power =pos_medium 3.IF Distance = medium AND Angle = neg_small THEN Power = neg_medium 4.IF Distance = close AND Angle = pos_small THEN Power = pos_medium 5.IF Distance = zero AND Angle = zero THEN Power = zero

9. 5. Structure of a Fuzzy Crane Controller

10. 6. Design and Implementation

11. Input 1 (Angle)

12. Input 2 (Distance)

13. Output (Power)

14. Steps involved • Design of inference structure. • Definition of Linguistic variables. • Create initial fuzzy logic rule base using all available knowledge (expert knowledge) on how the system should work. • Off-line debugging • On-line debugging.

15. 7. A comparison of performance on different hardware platforms.

16. 8. Conclusion • Enables the use of experience and experimented results to deliver more efficient solutions. 2. Extends traditional automated control techniques by adding supervisory control capabilities. 3. In container controller case, provides a transparent and simple solution that is much harder to solve using conventional engineering.

17. Thank you….