Active Vibration Control for the Mitigation of Wheel Squeal Noise Based on a Fuzzy Self-Tuning PID Controller

Table 5

Comparison of SPL reduction (dB) in different frequencies by different control methods.

Frequency band/control method	125	160	200	250	315	400	500	630	800	1000	1250	1600	2000	2520	3200	4000	5000
Wheel dithering [25]	6	−26	5	−37	−14	3	19	7	2	8	16	−11	−25	−12	6	50	32
Rail dithering [25]	−27	−33	−57	−58	−51	0	−4	−28	8	2	−5	−8	−3	2	−12	8	3
Shunted piezoelectric [26]	−13	−12	11	12	8	−8	−10	−6	−9	−46	−54	−24	3	−14	−14	0	2
Active control	−37	−5	−30	−65	−27	−24	3	0	−9	−1	−16	−6	−14	−8	−7	27	17