Presentation on theme: "Why Fuzzy system What are fuzzy systems Pure fuzzy system."— Presentation transcript:
Why Fuzzy system
What are fuzzy systems
Pure fuzzy system
TSK fuzzy systems
Fuzzy system with fuzzier and defuzzier
Fuzzy system as open-loop controller
Fuzzy system as closed-loop controller
Fuzzy washing machine They were produced by Matsushita Electric Industrial Company in Japan around They use a fuzzy system to automatically set the proper cycle according to the kind and amount of dirt and the size of the load the fuzzy system used is a three-input-one-output system, where the three inputs – measuremeqts of-dirtiness – type of dirt – load size – output is the correct cycle.
Fuzzy washing machine Sensors supply the fuzzy system with the inputs. The optical sensor sends a beam of light through the water and measures how much of it reaches the other side. The dirtier the water, the less light crosses. also has a load sensor that registers the volume of clothes. Clearly, the more volume of the clothes, the more washing time is needed summarized in a number of fuzzy IF-THEN rules that were then used to construct the fuzzy system.
Digital Image Stabilizer IF all the points in the picture are moving in the same direction, THEN the hand is shaking IF only some points in the picture are moving, THEN the hand is not shaking the stabilizer compares each current frame with the previous images in memory. If the whole appears to have shifted, then according to (1.10) the hand is shaking and the fuzzy system adjusts the frame to compensate. Otherwise, it leaves it alone.
Fuzzy Systems in Cars An automobile is a collection of many systems- engine, transmission, brake, suspension, steering, and more-and fuzzy systems have been applied to almost all of them. Nissan has patented a fuzzy automatic transmission that saves fuel by 12 to 17 percent Nissan's fuzzy automatic transmission device summarized these heuristics into a collection of fuzzy IF-THEN rules that were then used to construct a fuzzy system to guide the changes of gears.
Fuzzy Systems in Cars Nissan also developed a fuzzy antilock braking system. The challenge here is to apply the greatest amount of pressure to the brake without causing it to lock. The Nissan system considers a number of heuristics, for example, IF the car slows down very rapidly, THEN the system assumes brake - lock and eases up on pressure
Fuzzy Control of a Cement Kiln The fuzzy system (fuzzy controller) had four inputs and two outputs (which can be viewed as two fuzzy systems). The four inputs are: – (i) oxygen percentage in exhausted gases, – (ii) temperature of exhaust gases, – (iii) kiln drive torque – (iv) litre weight of clinker (indicating temperature level in the burning zone and quality of clinker). The two outputs are: – (i) coal feed rate – (ii) air flow. collection of fuzzy IF-THEN rules were constructed that describe how the outputs – IF the oxygen percentage is high and the temperature is low, THEN increase air flow – IF the oxygen percentage is high and the temperature is high, THEN reduce the coal feed rate slightly
Fuzzy Control of Subway Train The most significant application of fuzzy systems to date may be the fuzzy control system for the Sendai subway in Japan. On a single north-south route of 13.6 kilometers and 16 stations, the train runs along very smoothly. The fuzzy control system considers four performance criteria simutaneously: safety, riding comfort, traceability to target speed, and accuracy of stopping gap
Fuzzy Control of Subway Train The fuzzy control system consists of two parts: – the constant speed controller – automatic stopping controller The constant speed controller was constructed from rules such as: – For safety; IF the speed of train is approaching the limit speed, THEN select the maximum brake notch – For riding com f ort; IF the speed is in the allowed range, THEN do not change the control notch The automatic stopping controller was constructed from the rules like: For riding comfort; IF the train will stop in the allowed zone, – THEN do not change the control notch – For riding corn f ort and safety; IF the train is in the allowed zone, THEN change the control notch from acceleration to slight braking
What Are the Major Research Fields in Fuzzy Theory