An Improved Method of EWT and Its Application in Rolling Bearings Fault Diagnosis

Table 7

Feature vectors.

Bearing state	Sample label	Permutation entropy
		E1	E2	E3	E4	E5
Normal	1	1.163	1.988	2.351	2.844	2.676
		1.205	1.519	1.957	2.119	2.368
		1.190	1.523	1.960	2.125	2.358
Outer race fault 1	2	3.092	3.229	3.493	2.888	2.092
		3.109	3.244	3.409	2.991	2.414
		3.144	3.188	3.468	2.966	2.069
Outer race fault 2	3	1.245	2.018	3.877	3.549	3.895
		1.140	1.784	3.952	3.366	3.928
		1.158	1.984	3.950	3.589	3.894
Inner race fault 1	4	1.205	1.519	1.957	2.119	2.368
		1.190	1.524	1.960	2.125	2.358
		1.199	1.492	1.961	2.133	2.346
Inner race fault 2	5	3.008	3.474	2.859	3.410	3.259
		3.012	3.497	2.764	3.678	2.892
		2.982	3.571	2.855	3.390	3.299
Rolling element fault 1	6	1.526	2.197	4.148	3.148	3.165
		1.486	1.995	4.118	3.171	3.111
		1.484	2.020	4.114	3.239	2.982
Rolling element fault 2	7	1.140	2.164	4.406	2.802	3.088
		1.158	2.120	4.323	2.880	2.972
		1.161	2.143	4.325	2.835	2.972