Subject Code: BME054
Subject Name: Mechatronics Systems
Course: B.Tech (Semester V)
Maximum Marks: 70
Duration: 3 Hours
Exam Year: 2024–25
Sections: A, B, and C
SECTION A – Short Answer Questions (2 × 7 = 14 Marks)
Attempt all questions briefly.
a. What is the principle of a relay?
b. Define a Programmable Logic Controller (PLC).
c. List the types of buses used in a PLC.
d. What instruments are used to measure linear velocity?
e. List the different types of timers.
f. Define an electromechanical system.
g. Define transfer function.
SECTION B – Medium-Length Questions (7 × 3 = 21 Marks)
Attempt any three of the following.
Sketch and explain the basic architecture of a PLC and describe the function of each element.
Explain the ratchet and pawl mechanism.
Describe the specifications of a stepper motor in detail.
Identify elements of a closed-loop control system in an automatic water level controller and describe their functions.
Explain the function of an air filter with a neat sketch.
SECTION C – Long / Analytical Questions (7 × 5 = 35 Marks)
Attempt one part from each question.
Q3. System Modelling
a. Derive a mathematical differential equation for a system governed by an electric motor.
OR
b. Describe adaptive control and digital logic controller.
Q4. Actuation and Transducers
a. Discuss the following actuation systems: Self-excited wound field shunt DC motor
Self-excited wound field series DC motor Stepper motor
Induction motor
OR
b. Write short notes on: Thermocouple
Piezoelectric transducer Incremental encoder
Photovoltaic transducer
Q5. Sensors and Robots
a. Discuss the actuation system including Stepper and Induction Motors (repeated emphasis on DC configurations).
OR
b. Explain the function of a capacitive sensor in a robot’s end effector.
Q6. PLC and Robotics
a. Explain how a PLC can handle an analog input.
OR
b. Discuss possible design solutions for a pick-and-place robot.
Q7. Mechatronics System Design
a. Design a mechatronics system for an automatic car park system — describe its sensors, actuators, and control logic.
OR
b. Draw ladder logic diagrams for:
(i) Two normally open switches must be closed for a motor to operate.
(ii) Either of two normally open switches can be closed to energize a coil.
(iii) A motor starts by pressing a spring-return start button and stops by pressing a spring-return stop button.
Key Topics for Study
PLC architecture: I/O modules, CPU, buses, memory organization
Electromechanical systems: sensors, actuators, and transducers
Actuation mechanisms: DC motors, induction motors, stepper motors
Transducers: Thermocouple, Piezoelectric, Encoder, Photovoltaic
Control systems: Open vs Closed loop, transfer functions, adaptive control
Robotics: Capacitive sensors, pick-and-place systems, automation design
PLC programming: Ladder logic, timers, analog input handling
Study Tips
Understand PLC operations — focus on input/output interfacing, control logic, and ladder diagrams.
Revise actuation mechanisms and their control principles (especially stepper & DC motors).
Draw clean block diagrams for sensors and transducers — labeling is key.
Practice ladder logic questions — they are often asked for 7 marks.
Review mechatronic system design examples, e.g., car parking or robotic arm control systems.
