Table 5.

The accuracy of FDT and contrast PDR system.

Field	User	SONY Z2		SONY Z3		HTC M7
		PDR	FDT	PDR	FDT	PDR	FDT
NCKU	A	12.07	0.61	29.96	0.66	2.43	1.09
143 m	B	14.00	0.66	33.44	0.68	1.30	0.74
	C	12.45	0.60	32.90	0.64	0.91	0.64
	D	9.40	0.61	30.42	0.77	5.79	0.66
III	A	3.19	0.89	1.84	3.86	1.28	0.93
162 m	B	1.98	0.99	3.28	1.33	0.78	0.61
	C	4.48	0.86	7.12	1.19	1.14	1.16
	D	5.07	1.17	1.71	0.87	4.36	3.87
Enterprise	A	3.47	3.39	6.99	1.66	13.03	0.54
175 m	B	9.91	2.31	3.47	0.89	11.12	1.19
	C	3.02	1.75	1.48	1.94	7.98	0.82
	D	2.59	3.38	2.53	1.71	8.79	1.25
	Mean of FDT: 1.3, Standard deviation: 0.94
:	Mean of contrast PDR: 8.21, Standard deviation: 9.26
	Unit: loop closure error/travelling distance (%)