Author´s reply [to comments on ´Research on estimating smoothed value and differential value by using sliding mode system´]

The basic theoretical tool for a nonlinear filter estimating the smoothed value and the differential value from the data corrupted by impulsive noise at the ultrasonic sensors in our paper (Emaru and T. Tsuchiya, "Research on estimating smoothed value and differential value by using sliding mode system," IEEE Trans. Robot. Autom., vol. 19, no. 3, pp. 391-402, Jun. 2003) is the same as the theory proposed in the earlier paper by J. Q. Han and W. Wang (J. Q. Han and W. Wang, "Nonlinear tracking-differentiator" (in Chinese), J. Syst. Sci. Math. Sci., vol. 14, no. 2, pp. 177-183, 1994). Until now, we had not known the Journal of System Science and Mathematical Science (in Chinese), and had not read the paper listed in their comments. We should have cited their paper in our paper. We correct our failure of not citing their paper, and we sincerely apologize for our mistake.