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0593_C12_fm  Page 438  Monday, May 6, 2002  3:11 PM





                       438                                                 Dynamics of Mechanical Systems



                                                                                D
                                                                                       Y

                        O
                                                                            Ω
                           β    1
                            1
                                                                                β
                                                                                   S
                                        2
                                        β
                                      2
                                                                                              α
                       FIGURE P12.2.9                      FIGURE P12.2.10
                       Double, unequal-rod pendulum with   A disk spinning in a free-turning yoke and supported
                       relative orientation angles.        by a shaft S.
                       measured by the angle β and the rotation of S in its bearings be measured by the angle α
                       as shown. Recall that this system has two degrees of freedom, which may be represented
                       by the angles  α and  β. By following the procedures outlined in Problems P11.6.8 and
                       P11.9.8, use Kane’s equations to determine the governing equations of motion.
                       P12.2.11: See Problems P11.6.7 and P11.9.7. Consider again the right circular cone C with
                       altitude  h and half-central angle rolling on an inclined plane as in Figure P12.2.11. As
                       before let the incline angle be β and let the position of C be determined by the angle φ
                       between the contacting element of C and the plane and a line fixed in the plane as shown.
                       Let   be the element length of C, and let r be the base radius of C. Let O be the apex of
                       C, and let G be the mass center of C. Finally, let ψ measure the roll of C, as shown in Figure
                       P12.2.11. This system has one degree of freedom (see Problem P12.2.11). Use Kane’s
                       equations to determine the equations of motion.



                                                                                      C
                                                              O
                                                                      α       G
                                                                      φ
                                                                                 r   ψ

                       FIGURE P12.2.11                                  β
                       A cone rolling on an inclined plane.


                       Section 12.3 Lagrange’s Equations

                       P12.3.1 to P12.3.10: Repeat Problems P12.2.1 to P12.2.10 by using Lagrange’s equations to
                       obtain the equations of motion. Compare the analysis effort with that of using Kane’s
                       equations.
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