Page 14 - June
P. 14

METALWORKING EQUIPMENT AND TOOLS

               The theoretical feasibility consists in            of  the  integral of  the  weighted modulus of
        the  requirement  that  the  calculated  values           error (IWMO), tuned to double proportions and
        of  the  parameters  of  the  synthesized  drive          Newton's binomial (Figure 1, a). It has a close-
        correspond  to  the  physical  meaning  of  the           to-unity  frequency  response  without ripple
        problem.  In  other  words,  the  values  of  the         in the  passband  and  a  rather  uneven  group
        moments  of  inertia,  stiffness,  damping                delay (Figure 1, d). The stop band is smooth,
        coefficient, motor parameters and controller              monotonically  decreasing,  with a  low rate  of
        settings must have non-zero positive values               signal suppression;
        corresponding  to  the  ranges  of  possible              ●  Chebyshev,  Legendre,  Legendre-Papoulis
        changes in the parameters of real-life drives.            filters can be used when the rate of damping
        To set up the drive for operation in accordance           of  oscillations  outside the  passband  is more
        with the selected polynomial, it is necessary             important  than  the  type  of  frequency  and
        to adhere  to certain  relationships between              transient  characteristics  (Figure  1,  b).  They
        the  moments  of  inertia  and  the  rigidity  of         are characterized by the presence of ripple in
        structural  elements.  In  a  real  drive,  with          the  amplitude  characteristic in the  passband,
        a  certain  mass  of  the  unit,  it is not  always       but provide a steeper roll-off in the frequency
        possible to select components  to ensure                  response  in  the  stopband  compared  to  filters
        these ratios (practical feasibility).                     with a flat frequency response. Tuning the drive
        The  reference  polynomials from  [1] can  be             in machine tools to none of these polynomials in
        conditionally divided into several groups [4,             most cases is not possible due to the complexity
        5]:                                                       of the implementation of mechanical (requires
               With a flat amplitude characteristic in            high rigidity and a small moment of inertia of
        the passband, which include:                              the screw) and electrical (large required gains
        ●  Butterworth  filter  based  on  the  minimum           make the drive unstable) drive parameters.

















               Filters with a linear phase characteristic include Bessel, Gaussian filters and filters with a
        linear phase of 0.05° and 0.5° (Figure 1, c). If filters with a flat frequency response provide the
        required type of amplitude characteristic, then these filters are designed to obtain a constant
        group delay in the passband, which corresponds to a linear phase change (Figure 1, d). Gaussian
        crossover filters -6 and -12 dB combine the positive characteristics of various filters. These
        filters are a transition from the Gaussian filter to the Chebyshev filter. They have a smooth
        amplitude characteristic, a linear phase and a steep slope in the stop band (Figure 1, e).


    14     Stanochniy park
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