MECH-3 - 16(1)(1)

7/31/2019 MECH-3 - 16(1)(1)

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IFET COLLEGE OF ENGINEERING

MECHANICAL ENGINEERING

MECHATRONICS-UNIT-III

1. Explain Mechanical building blocks and electrical building blocks with diagram. (8+8)

1. Basic elements of mechanical system- Springs, dashpots, masses

2. Properties of MBS- mass directed, mechanical tension, vibration.

3. Input & output of MBS - Force, acceleration, fluid resistance.

4. Examples of MBS – springs, dashpot, masses

5. Spring represented by- stiffness, force, displacement.

6. Diagram for spring - applied force, extension, constant, spring, input, output.

7. Masses represented by- mass, force, acceleration.

8. Diagram of mass & inertia – Force, acceleration, mass.

9. Dash pot represented by- damping ratio, force, velocity.

10.Diagram of dashpot - Velocity of piston, a constant, force, resistance, fluid.

11.Diagram of spring-dashpot-mass – force, stiffness, mass, damper.

12. Advantages of MBS models- stiffness, load withstand, vibration less.

13.Basic EBS- inductors, capacitors, resisters

14.Equation of PD of inductors – sum,

15.Equation of PD of capacitors-

16.Equation of resistor PD-

17.Laws of EBS - Kirchhoff’s current law, voltage law, combination.

18.Node & mesh analysis- Total current flowing, towards the junction, from the junction.

19.Diagram for node analysis- Applied voltage, resistance. Current, point.

20.Diagram for mesh analysis- Applied voltage, resistance, current, loop.

21.Diagram of resistor-capacitor – Applied voltage, resistance, capacitor, current.

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22.Diagram of resistor-inductor-capacitor - Applied voltage, resistor, capacitor,

inductance, current.

23.Diagram of resistor-inductor – Resistance, applied voltage, inductance..

24.Mechanical vs electrical – analogies, velocity: voltage, capacitance: inertia.

25.Applications of electrical systems- LCR circuit, find potential difference, form circuit.

2. Discuss briefly about the fluid and thermal system with neat sketches and relations. (8+8)

1. Fluid building block- electrical resistance, inductance and capacitance.

2. Components of FBS -

3. Differentiate hydraulic & pneumatic -

4. Hydraulic resistance- flow resistance, liquid flow, changes in pipe diameter.

5. Diagram of FBS – Volumetric rate of flow, pressure difference, flow control.

6. Symbol of hydraulic resistance – valve, Rate of flow, pressure difference.

7. Hydraulic capacitance- energy storage, results, potential energy.

8. Diagram of hydraulic capacitance-

9. Explain hydraulic inertance- equivalent inductance, electrical, spring, mechanical.

10.Diagram of hydraulic inertance- Mass, force, area.

11.Applications of fluid block -

12.Fluid system-

13.Classifications of thermal system- Thermal resistance, thermal capacitance.

14.Thermal resistance- rate, heat flow, temperature difference, resistance.

15.Equations of conduction & convection - 16.Thermal capacitance – measure, store of energy, system.

17.Diagram of thermal block-

18.The first order differential equation of thermal system-

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19.Lumped parameter considered as -

20.Thermal system Equations arrived by-

21. Applications of thermal system-

22.Advantages of TBB-

23.Fluid vs thermal system-

24.Building blocks in design-

25.Building blocks in research-

3. Describe the following with diagrams and equations (6+10)

(a) Rotational-translational systems

1. Rotational-translational systems- Rotational motion, pinion, translational motion, racks.

2. Examples of RTS – Racks & pinion, lead screws shafts, pulley & cable systems.

3. Components of RTS- Input torque, output torque, rack, pinion.

4. Equation of torque in RTS - (Tin-Tout)=I(dw/dt )

5. Diagram of rack and pinion-

6. Equation of force with friction -

7. Output Equation of RTS-

8.Applications of rack and pinion-

9. Advantages of RTS -

(b) Electromechanical systems

10.Electromechanical devices- Potentiometer, motor, generators.

11.Use of potentiometer- input, rotation, output, potential difference.

12.Diagram of rotary potentiometer- Angle swept, slider, potential difference, output.

13.Equation of rotary potential meter- vo, V.

14.Diagram of DC motor driving a load-

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15. Diagram of one wire of armature-

16. Armature controlled motors-

17.Draw DC motor circuits and explains with equations-

18.Field controlled motors and give its diagram-

19.Circuit diagram of armature controlled motor-

20.Net torque equation of field controlled motor-

21.Net torque equation of armature controlled motor-

22.Compare armature and field controlled motors-

23.Characteristics of armature controlled motors-

24.Characteristics of field controlled motors-

25.Applications of armature and field controlled motors-

4. Explain about continuous and discrete process controllers and their modes. (8+8)

1. Need of closed loop control- used to compare the output of a system with the required

condition and convert the error into a control action designed to reduce the error.

2. Error signal-

3. Control mode- Number of ways by which a control unit can react to an error signal andsupply an output for correcting elements.

4. Applications of sequence operating machines-

5. PLC and its uses in controlling-

6. Compare PLC with computer-

7. Lag in control system-

8. Example of lag in control system-

9. Steady state error-

10.Diagram of unity feedback system and explain it-

11.Elements of unity feedback system-

12.Equation of unity feedback system-

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13.control modes used in continuous and discrete controls-

14.Looking back-

15.Diagram of PI control and its characteristics-

16.Diagram of controlled output with time of proportional action-

17.Diagram of controlled output with time of integral action-

18.Equation of proportional constant, derivative constant and integral constant-

19.Equation of proportional band and change in output-

20.Transfer function of proportional controller-

21.Offset in proportional mode of control-

22.Application of proportional mode of control-

23.Electronic proportional controller-

24.Diagram of electronic proportional controller-

25.Equations of voltage of proportional control-

5. Explain the following with neat diagrams and its characteristics. (4*4)

(a) Two step mode

1. Example of two step mode of control- Bimetallic thermostat.

2. Working of two step mode control- This action tends to be used where changes are

taking place very slowly.

3. Diagram of two step control- Heater supply, temperature, controller switch point.

4. Characteristics of two step mode of control- Is not very precise, but it does involve

simple device and is thus fairly cheap.

5. Diagram of oscillations with two step control- Control switch position, time,

temperature.

6. Diagram of two control with the controller switch points- Heater supply, dead band,

temperature, controller switch point.

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25.Integral time constant-

6. Discuss briefly about digital and velocity controllers. (8+8)

1. In which control process digital controllers are used-

2. When the direct digital control is used- The digital controller requiring inputs which

are digital, process the information in digital form and give an output in digital form.

3. Operating cycle of events of digital controllers-

4. Accuracy of digital control-

5. Characteristics of digital controller-

6. Computer controlled system-

7. Controller performance-Receives input from sensors, Executes control programs,Provides the output to the correction elements.

8. Diagram of system with proportional control and explain it- Controller output, error,

proportional band.

9. Diagram of system with integral control and explain it- Integrator, summing

amplifier.

10.Diagram of system with derivative control- Constant rate of change of error with time,

time.

11.Transfer function equation of proportional control- Change in output(s)/ E(s)

12.Transfer function equation of integral control- (1/s)K 1

13.Transfer function equation of derivative control- (Iout-Io)/ E(s)

14.Controller tuning-

15.Process reaction curve and explanation-

16.Basic methods of controller tuning-

17.Velocity control- A second order system with proportional control system will take more

time to reach the required output when step input is given.

18.Need of velocity control-

19.Velocity feedback- Use of second feedback loop that gives the measurement related to

the rate at which the displacement is changing.

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20.Diagram of velocity control- Input, summing amplifier, servo amplifier, motor,

rotational output, gear and screw, load, output position.

21.Block diagram of velocity control- Input, summing amplifier, servo amplifier, motor,

rotational output, gear and screw, load, output position.

22.Advantages of velocity control-

23.Characteristics of velocity control-

24.Compare digital control and velocity control-

25.Applications of velocity control-

7. i) Explain about adaptive control. (4)

ii) Discuss briefly about the logic controllers with diagrams. (12)

1. Logic control- The sequence of steps required to perform a specific function.

2. Use of combinational logic gates-

3. Application of sequential logic gates-

4. Compare decimal and binary system-

5. Logic gates used as controllers-

6. Use of AND gate and its diagram- Is a basic digital logic gate that implements

logical conjunction.

7. Standard symbol of AND gate and its truth table-

8. Use of OR gate and its representation diagram- The OR gate is a digital logic

gate that implements logical disjunction.

http://en.wikipedia.org/wiki/Logical_conjunction

http://en.wikipedia.org/wiki/Logic_gate


http://en.wikipedia.org/wiki/Logical_disjunction

http://en.wikipedia.org/wiki/Logical_conjunction



http://en.wikipedia.org/wiki/Logical_disjunction

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9. Symbol of OR gate and its truth table-

10.Use of NOT gate and its representation diagram- Accepts only one input and the

output is the opposite of the input.

11.Symbol of NOT gate and its truth table-

12.Use of NAND gate and its representation diagram-The output is high when either of

inputs A or B is high, or if neither is high.

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13. Pulse diagram of NAND gate-

14.Boolean equations for AND, NOT, NAND and OR gate-

15.Use of NOR gate- The output is high only when neither A nor B is high.

16.Diagrams of NOR gate and its truth table-

17. XOR gate- The output from this gate will be a 1 only when one or other of the input is a

1.

18.Diagram of XOR gates and its truth table-

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19.Applications of logic gate controllers- Used to make flip-flops and other vital

electronic components.

8. i) Briefly discuss about the microprocessor control with block diagram. (12)

1. Microprocessor- A program controlled semi conductor device (IC), which fetches (from

memory) decodes and executes instruction.

2. Explain ALU and control unit- Perform arithmetic and logic functions on eight bit

variables.

3. Register and its uses- It has eight addressable 8-bit register and two 16-bit register.

4. Use of accumulator register and status register- Used in arithmetic, logic, load, and

store operation and in input/output operation.

5. Function and its use of program counter register and temporary register- Stores the

address of the next instruction to be fetched.

6. Memory address register and instruction register- CPU stores opcode in register.

7. General purpose register and stack point register- B,C,D,E,H,L are 8-bit general

purpose register. Reserved area of memory in the RAM.

8. Address and data bus-

9. Serial I/O control- Used to transmit data bit by bit to reduce cost of cabling.

10.Timing and control status- Operation is synchronized with the help of clock signal.

11.Address buffer and data buffer- Is an 8-bit bi-directional buffer.

12. HOLD and HLDA-

13.INTA and INTR-

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14.TRAP in interrupt control- Interrupt control has five interrupt input. TRAP is one of

the interrupt input.

15.Use of RESET IN and RESET OUT-

16.ALE and interrupt control- The processor fetches, decodes and execute instruction insequence.

17.ROM, PROM and EPROM-

18.Incrementer and Decrementer- 16-bit register is used to increment or decrement the

program counter or stock pointer as a execution of instruction related to them.

19.SID and SOD- Serial I/O control provides SID and SOD for serial communication.

20.Applications of MP- Greater variety of program become feasible.

ii) Explain about PID controllers. (4)

21.Diagram of controlled output with time of PID control- Resister, capacitor.

22.Advantage of PID control- Considering this as a proportional controller which has

integral control to eliminate the offset error and derivative control to reduce time lags.

23.Three mode controllers- Combining all three modes of control enable a controller to be

produced which has no offset error and reduce tendency for oscillation.

24.Equation of transfer function of PID controller- Transfer function= K Pe+(1/s)

(K 1)E(s)+sK D(s)

25.Diagram of error signal of PID controller and explain-

MECH-3 - 16(1)(1)

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