## Mechatronics - Dec 2013

### Mechanical Engineering (Semester 6)

TOTAL MARKS: 100

TOTAL TIME: 3 HOURS
(1) Question 1 is compulsory.

(2) Attempt any **four** from the remaining questions.

(3) Assume data wherever required.

(4) Figures to the right indicate full marks.
**1 (a)** Differentiate between microprocessor and microcontroller.(5 marks)
**1 (b)** How steady state error of a control system is determined? How it can be reduced?(5 marks)
**1 (c)** Obtain the transfer function of the system defined by the following state-space equations: $$ \begin{bmatrix}x_1\\x_2 \\x_3 \end{bmatrix} = \begin{bmatrix}
0 &1 &0 \\0 &0 &1 \\-5 &-25 &-5 \end{bmatrix} \begin{bmatrix}x_1\\x_2 \\x_3 \end{bmatrix}+ \begin{bmatrix}
0\\25 \\-120 \end{bmatrix} u \\ y= \begin{bmatrix}
1 & 0 & 0 \end{bmatrix} \begin{bmatrix}
x_1\\x_2 \\x_3 \end{bmatrix} $$(5 marks)
**1 (d)** Write short note on pneumatic actuator.(5 marks)
**2 (a)** Explain the architecture of 8051 microcontroller with neat sketch.(10 marks)
**2 (b)** For a system, $$ G(s) h(s) = \dfrac {k}{s^2 (s+2)(s+3) }. $$ Find the value of k to limit steady state error to 10 when input to system is $$ \left \{ 1+10t + \dfrac {40}{2} t^2 \right \} $$(10 marks)
**3 (a)** Two double acting pneumatic cylinders A and B are selected for an industrial application. The sequence of movement for cylinder is as indicated below. A+B+, (AB)- Draw pneumatic circuit for the above sequence of operation.(10 marks)
**3 (b)** Draw Bode plot for a unity feedback system with $$ G(S) H(S) = \dfrac {3 (s+1) (s+6) }{s^2 (s^2 = 18 s + 400)} $$ Comment on G.M, P.M, and stability.(10 marks)
**4 (a)** Describe the Architecture of PLC with block diagram with suitable industrial applications.(4 marks)
**4 (b)** Sketch the complete root locus for the system having, $$ G(S) H(S) = \dfrac {K} {s(s+1) (s+2)(s+3)} $$(8 marks)
**4 (c)** Consider the liquid-level system shown in the fig. 1. In the system Qt is steady-state flow rate, H_{1} and H_{2} are steady-state heads. h_{1} and h_{2} small deviation of head from its steady state value q and q_{2} are small deviations of inflow and outlflow rate from its steady values. Obtain the transfer function of the system.
(8 marks)
**5 (a)** Two double acting hydraulic cylinders A, B are selected for an industrial application. The sequence of movement for cylinder is as indicated below-

Delay B+A+, Delay(AB)-

Draw the electro-hydraulic circuit using 4/3 double solenoid ass final directional control valves. The auxiliary condition is that single cycle or multi-cycle can be selected.(10 marks)
**5 (b)** The open loop T.F. of unity feedbacks system is $$ G(S) = \dfrac {K}{S(1+TS)} $$ for this system overshot reduces from 0.6 to 0.2 due to change in "K" only. Show that- $$ \dfrac {T K_1-1} {TK_2-1} = 43.33 $$ where K_{1} and K_{2} are values of K for 0.6 and 0.2 overshot respectively.(10 marks)
**6 (a)** For a system with characteristics equation, F(S)=s^{6}+3S^{5}+4S^{4}+6S^{3}+5S^{2}+3S+2=0, examine stability using Routh's criterion.(6 marks)
**6 (b)** Define (a) Gain Margin and (b) Phase Margin.(6 marks)
**6 (c)** Differentiate between stepper motor and servo motor.(8 marks)

### Write short notes on:

**7 (a)** Advantages of PI controller(5 marks)
**7 (b)** Transient response of a control system.(5 marks)
**7 (c)** Polar plot.(5 marks)