Abstract: | This paper discusses the problem of speed estimation in very low speed servo systems. Speed estimation can be easily done by such conventional tools as tachometers, observers, numerical differentiation, and so on. However, speed estimation for very low speed systems still includes some engineering problems regarding precision. This paper proposes a simple way to derive a speed estimate by using the output difference over a long period of time and the sequence of inputs during the same period. We have also verified this method through an experiment on a hydraulic servo system. © 1999 Scripta Technica, Electr Eng Jpn, 126(4): 63–69, 1999 |