A very typical problem of electromechanical position control is an electric motor driving a load that has one dominant vibration mode. The problem arises in computer-disk-head control, reel-to-reel tape drives, and many other applications. A schematic diagram is sketched in Fig. 2.51. The motor has an electrical constant Ke, a torque constant Kt, an armature inductance La, and a resistance Ra . The rotor has an inertia J1 and a viscous friction B. The load has an inertia j1 The two inertias are connected by a shaft with a spring constant k and an equivalent viscous damping b. Write the equations of motion.
Figure 2.51 Motor with a flexible load
