Page 262 - Robot Builders Source Book - Gordon McComb
P. 262

250                     Feeding and Orientation Devices

        mation of it can be received when W= 0, neglecting friction.) This condition exists
        during time t 2, which is defined as





        The displacement S^ then is





        Obviously, for the second half-period (section KM) we receive correspondingly (to
        expressions a, b, c, and d) a set of following formulas:











        This speed value is negative while friction force acts in the positive direction:












        where W=-ju(g+S cr'smj3).
           Summarizing these two slides we obtain the resulting displacement of the body
        relatively to the tray in the bowl. A more precise description of the relative movement
        of the body on the tray follows. We express the absolute coordinates of the body X and
        Y in the following form:



        where -x 0(f) and y 0(t) are coordinates of the tray; x and y are relative coordinates of
        the body. Then, rewriting, (7.31) we obtain





        For the case of dry friction we have F = -ji/ATsign x, and for the normal reaction on the
        body correspondingly N = my 0 (t) + rag cos a.
           Then the most important case of transportation without rebounds, the relative
        motion of the body along the tray, becomes as follows:


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