🚀 go-pugleaf

    Dear netters,

        The following question refers to :

        Bayliss C. McInnis and Cheng-Kang Frank Liu (1986) "Kinematics
        and Dynamics in Robotics: A Tutorial Based Upon Classical
        Concepts of Vectorial Mechanics",IEEE Journal of Robotics
        and Automation. Vol:RA-2, No:4, December 1986.

        If you don't have this article please ignore this posting.

        The authors differentiate equation (2) on page 181 to get
        equation (3).

        (2):
            Vp = Vi + P(o)i/i + Wi X Pi

            to get

        (3):
            Ap = Ai + P(oo)i/i + 2Wi X P(o)i + W(dot)i X Pi +
                 Wi X ( Wi X Pi) ^
                                 |
                                 |
            I only get one of these. ie. a one instead of a two.

            Please, someone, explain.
            How is this done, or is this a typo ?
            If it is a typo, what is the correct answer.

        PS: I hope this makes sense.
            Apologies for the way that I have done sub/super
            scripts.

    Much thanks in advance.
    Richard.
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| Some of us are poets, some of us are not. | puchm@cutmcvax.cs.curtin.edu.au |
| Richard Puchmayer, Masters Student at     |         Sorry but I             |
| Curtin University of Western Australia    | don't know any other addresses  |
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