Mechatronics - May 2012

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) Explain mechatronics system design process with the help of neat diagram or flow chart.(4 marks) 1 (b) Explain the functions of port 0, port 1 and port 2 in 8051 microcontroller.(6 marks) 1 (c) Consider the system defined by

Where y is output and u is input of system. Obtain the state space representation of system.(6 marks) 1 (d) Explain Routh's criteria and Hurwitz criteria in stability analysis of control system.(4 marks) 2 (a) Explain the architecture of 8051 microcontroller with neat sketch.(10 marks) 2 (b) The open loop transfer function of unity feedback system is

By what factor should the gain 'k' be multiplied with so that damping ratio is increased from 0.3 to 0.8, by what factor time constant 'T' should be multiplied so that damping ratio is reduced from 0.6 to 0.4.(10 marks) 3 (a) Two double acting pneumatic cylinders A, B are selected for an industrial application. The sequence of movement for cylinder piston is as given below -
A-DelayB+(A+B-)
Further it is proposed to use single solenoid spring return 5/2 and double solenoid 5/2 as final directional control valves for cylinders A and B respectively. Design electropneumatics circuit for the proposed sequence.(12 marks) 3 (b) Write a program to perform -
i) Divide the content of r0 by r1
ii) Store the result in r2 (answer) and r3 (remainder)
iii) Then restore the original content of r0.(8 marks) 4 (a) A mixer process control problem is shown in figure 1. The mixer motor is to be used to stir the liquid automatically in the tank when the temperature and level reach the preset value. Draw a PLC ladder logic diagram to execute the operation.
(10 marks) 4 (b) Explain interfacing of LCD display (two line X 20 character) with 8051 microcontroller.(10 marks) 5 (a) Two double acting hydraulic cylinders A, B are selected for an industrial application. The sequence of movement for cylinder is as given below -
DelayA+(B+B-)_3timesA-
Draw the electrohydraulic circuit using 4/3 double solenoid as final directional control valves.(10 marks) 5 (b) Figure shows a system having transfer function

A PID controller is used with following specifications:
a.The derivative time constant=0.5s
b.Integral time constant=3s
c.Proportional gain=30.
Evaluate the following:
1.System type
2.Steady state error for step input
3.Stability of system. (10 marks)
(10 marks) 6 (a) Explain the factors to be considered for selecting a PLC for control application.(5 marks) 6 (b) Draw the bode plot and also comment on stability of control system having open loop transfer function
(10 marks) 6 (c) Write short note on servomotor.(5 marks) 7 (a) Sketch the complete root locus for the system having
(11 marks) 7 (b) A unity feedback system has open loop transfer function given below:

i) Obtain response equation against unit step input
ii) What is rise time?
iii) What is peak overshoot? (9 marks)