(SEM-VIII) THEORY EXAMINATION 2022-23 AUTOMATION & ROBOTICS

SECTION A

(Attempt all | 2 × 10 = 20 Marks)

(a) Automation in production system

Automation is the use of mechanical, electrical, and computer-based systems to operate and control production processes with minimal human intervention, improving productivity, quality, and consistency.

(b) Need for automation

Automation is needed to increase production rate, improve product quality, reduce labor cost, enhance safety, ensure consistency, and meet global competition.

(c) Part handling and feeding in automation

Part handling and feeding involve automatic movement, positioning, and orientation of components from storage to machines using conveyors, feeders, robots, and manipulators.

(d) Transfer line in automation

A transfer line is an automated production system where workpieces are transferred sequentially through a series of workstations performing specific operations.

(e) Laws of Robotics

Proposed by Isaac Asimov:

A robot must not harm humans

A robot must obey human orders

A robot must protect itself unless it conflicts with above laws

(f) Actuators

Actuators are devices that convert energy (electrical, hydraulic, or pneumatic) into mechanical motion to perform work.

(g) Mechanical switches

Mechanical switches are contact-type sensors used to detect position or limit of movement by physical contact, such as limit switches.

(h) Flow control valves

Flow control valves regulate the rate of fluid flow in hydraulic and pneumatic systems, controlling speed and motion of actuators.

(i) Teach pendant

A teach pendant is a handheld programming device used to manually guide and program robot movements.

(j) Reason for using robots in industries

Robots are used for higher productivity, precision, safety, continuous operation, and handling hazardous or repetitive tasks.

SECTION B

(Attempt any THREE | 10 × 3 = 30 Marks)

2(a) Considerations for automating a facility

Key considerations include production volume, product variety, cost justification, flexibility, reliability, maintenance requirements, labor availability, safety, and future expansion. Automation should be economically feasible and technically suitable for long-term benefits.

2(b) Types of transfer devices in industrial automation

Transfer devices include belt conveyors, roller conveyors, overhead conveyors, automated guided vehicles (AGVs), and robotic transfer arms.

Working of two devices:

Belt Conveyor:
Uses a continuous belt driven by pulleys to move parts between stations.

AGV:
AGVs follow predefined paths using sensors or magnetic guidance to transport materials automatically within factories.

2(c) Robotics control system

A robotic control system manages robot motion, speed, position, and task execution.
Types:                                                                       Point-to-Point Control

Continuous Path Control                                          Adaptive Control

Intelligent Control

Each type varies in precision and application.

2(d) AC and DC servo motors

DC Servo Motor:                                                      Fast response

High torque at low speed                                          Used in small robots

AC Servo Motor:                                                      High efficiency

Low maintenance                                                       Used in industrial robots

Both provide precise control of position and speed.

2(e) Task-level processing vs language-based programming

Task-level processing allows users to specify what task to perform rather than how to perform it. It overcomes complexity, reduces programming errors, improves flexibility, and simplifies robot programming compared to language-based methods.

SECTION C

3(a) Fluid power systems

Fluid power systems use pressurized liquids (hydraulics) or gases (pneumatics) to transmit power.

Advantages:
High power output, smooth motion, flexibility

Disadvantages:
Leakage, maintenance, energy loss

3(b) Hierarchical levels in industrial automation

Levels include:                                                              Device level (sensors, actuators)

Machine level (CNC, PLC)                                             Cell level

Plant level                                                                     Enterprise level

4(a) Robotic sensing devices

Characteristics include accuracy, resolution, sensitivity, repeatability, and response time.

Classification:                                                             Tactile sensors

Proximity sensors                                                         Vision sensors

Force and torque sensors

4(b) Vision-controlled robotic systems

Vision systems enable robots to identify objects, inspect quality, guide motion, and adapt to changing environments. Applications include inspection, assembly, welding, and material handling.

5(a) Forward kinematics of 3-DOF robot

Forward kinematics determines end-effector position from joint variables.

Advantages:
Simple computation, direct solution, less complex than inverse kinematics.

Inverse kinematics calculates joint variables from desired end-effector position.

5(b) Robot performance terms

Accuracy: Closeness to desired position                              Resolution: Smallest detectable movement

Repeatability: Ability to return to same position                 Speed: Rate of movement

Load capacity: Maximum payload                                       Reliability: Consistent performance over time

6(a) Gripper selection & servo motors

Gripper selection depends on object size, shape, weight, material, and environment.

AC and DC servo motors are used as robot drives due to precise speed and position control.

6(b) Position and orientation of end effectors

Determined using coordinate frames, homogeneous transformation matrices, and kinematic equations.

7(a) Robot cell design

Robot cell design involves layout planning, safety, accessibility, tooling, material flow, and control integration for efficient operation.

7(b) Factors for evaluating welding robots

Factors include payload, reach, accuracy, repeatability, speed, control system, sensor integration, and reliability.