Page 393 - Schaum's Outline of Theory and Problems of Signals and Systems
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STATE SPACE ANALYSIS                           [CHAP.  7
















                  In matrix form










                  Consider the mechanical system shown in Fig. 7-4. It consists of  a block with  mass m
                  connected  to a wall by  a  spring. Let  k, be the spring constant and  k, be the viscous
                  friction coefficient. Let the output  y(f) be the displacement of  the block and the input
                 x(f)  be the applied force. Find a state space representation of  the system.

                     By  Newton's  law we  have




                  The potential energy and kinetic energy of  a mass are stored in  its position and velocity. Thus,
                  we select the state variables q,(t) and q2(t) as





                  Then we  have






















                                                   y4
                                                    y(0
                                            Fig. 7-4  Mechanical system.
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