| 摘要 |
PURPOSE:To reduce fatigue of a sitting person, by optionally selecting either a burst control reciprocating a lumbar plate back and forth periodically or a fluctuation control moving it back and forth non-periodically. CONSTITUTION:Two kinds of automatic controls in addition to a manual control of a lumbar plate 28 can be selected, which are a burst control nearly periodically moving the lumbar plate 28 back and forth and a fluctuation control non-periodically moving it back and forth. In the fluctuation control, 1/f fluctuation waveform for instance has a non-periodical change which can be obtained by combining waveforms by fourier series. Moreover, for example, a time table is made from the amplitude and variation time obtained from a pseudo- fluctuation waveform corrected by removing minute frequency varying components and period varying component, which is difficult for the motor M5 to eliminate from 1/f fluctuation waveform. The motor M5 is controlled under the drive power and drive time expressed numerically for every step. |
