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0593_C04*_fm  Page 113  Monday, May 6, 2002  2:06 PM





                       Kinematics of a Rigid Body                                                  113







                                                                 b      θ
                                                                          G  r
                                                                                C
                                                                                 3
                                                                          r
                                                            h
                                                                          C
                                                                            2
                                                              θ


                                                            O
                       FIGURE 4.13.3
                       Geometry of rolling cones.                   a


                       and


                                                        h =+   +                              (4.13.20)
                                                           a r rsinθ
                        (Note that line OC  is inclined at 45°.) By eliminating h between these two expressions
                                        2
                       and then solving for a/r we obtain:

                                                  ar = (1 sinθ ) (cosθ − sinθ )               (4.13.21)
                                                        +
                       This is seen to be identical to the result of Eq. (4.13.18).







                       4.14 Closure
                       This completes our study and review of the fundamentals of kinematics. In the following
                       chapters, we will specialize and apply these kinematic principles to mechanisms,
                       machines, and multibody systems.





                       References
                       4.1. Kane, T. R., Analytical Elements of Mechanics, Vol. 2, Academic Press, New York, 1961, pp. 66,
                           97, 205, 318.
                        4.2. Kane, T. R., Dynamics, Holt, New York, 1968, pp. 63, 66.
                        4.3. Kane, T. R., and Levinson, D. A., Dynamics: Theory and Applications, McGraw-Hill, New York,
                           1985.
                        4.4. Huston, R. L., and Liu, C. Q., Formulas for Dynamic Analysis, Marcel Dekker, New York, 2001.
                        4.5. Cabannes, H., General Mechanics, Blaisdell, Boston, 1968, pp. 384–387.
                        4.6. Ramsey, A. S., Dynamics, Part II, Cambridge University Press, London, 1937, p. 160.
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