A tank gun turret is illustrated in Figure. The following details are given: The turret body of rotational inertia J is driven by an armature controlled DC motor. The motor has armature resistance r, winding inductance is l, motor torque constant Km and back-emf constant Ke. The motor drives the turret through a pinion gear-main gear set with radii r1 < r2 respectively. There is both a viscous friction (with coefficient B) as well as a self-centering rotational spring (with spring coefficient Ks) between the turret and the tank body. (Note: Rotor inertia of the DC motor can be ignored.)
1. Assuming that input of the system is the DC motor voltage Vm(s) and the output the angular position θL(s) of the turret on its rotation plane, use block diagram modeling to obtain the detailed block diagram of the system using only causal system components. (all sub-system transfer function blocks corresponding to the parts of the electric motor, gear set, turret block etc. and names of all intermediate signals should be clearly shown).
2. What is the “order” of this dynamic system?
3. Simplify your block diagram into a single transfer function, G(s) = θL(s)/Vm(s).
4. Now consider the scenario where the turret is controlled by a feedback controller to track a turret-angle set-point as the new input. The controller is such that it measures both the turret angle θL(s) as well as the turret rotational velocity ωL(s) and amplifies them with gains Kp and Kd before combining them with the reference. Sketch the new block diagram of the overall system. (You can use shortcut names such as G1(s), G2(s) etc. to show blocks that can be combined
together)