🔴 UNIT 4 – ROBOT MOTION & CONTROL
🤖 1. Robot Motion
✅ Definition
Robot motion refers to the movement of robot parts (links & joints) to perform a task.
Robot motion includes:
🔹 Types of Robot Motion
1️⃣ Translational Motion
Movement in a straight line.
✔ Forward
✔ Backward
✔ Left / Right
Example: Conveyor belt movement
2️⃣ Rotational Motion
Movement around an axis.
✔ Joint rotation
✔ Arm rotation
Example: Robotic arm rotating to pick an object
🤖 2. Motion Conversion
Definition:
Conversion of one type of motion into another.
Examples:
| Input Motion | Output Motion |
|---|---|
| Rotary | Linear |
| Linear | Rotary |
Devices Used:
-
Gears
-
Belts
-
Pulleys
-
Lead screws
🤖 3. Lagrangian Analysis of Manipulator
✅ Definition
Lagrangian method is used to analyze robot dynamics using:
-
Kinetic energy (T)
-
Potential energy (V)
Lagrangian Equation:
Where:
-
T = Kinetic Energy
-
V = Potential Energy
Purpose:
✔ Used to derive equations of motion
✔ Helps in control system design
✔ Used in robot dynamics
🤖 4. Control of Actuators
✅ Actuator
An actuator converts electrical energy into mechanical motion.
Types of Actuators:
🔹 1. Electric Actuators
-
Stepper motor
-
Servo motor
✔ Easy to control
✔ Used in most robots
🔹 2. Hydraulic Actuators
-
High force
-
Used in heavy robots
🔹 3. Pneumatic Actuators
-
Uses compressed air
-
Fast but less accurate
🤖 5. Robot Control Systems
🔹 Open Loop Control
-
No feedback
-
Simple
-
Low accuracy
Example: Timer-based robot
🔹 Closed Loop Control
-
Feedback present
-
High accuracy
-
Used in industrial robots
Example: Servo motor system
🤖 6. Robot Sensory Devices
✅ Definition
Sensors provide information about:
-
Position
-
Speed
-
Force
-
Environment
Types of Sensors:
| Sensor | Function |
|---|---|
| Position sensor | Joint position |
| Velocity sensor | Speed |
| Proximity sensor | Object detection |
| Touch sensor | Contact |
| Vision sensor | Image capture |
| Force sensor | Pressure detection |
🤖 7. Robot Motion Control System
Components:
-
Controller
-
Actuator
-
Sensor
-
Feedback loop
Control Process:
-
Receive command
-
Compare with actual position
-
Generate error signal
-
Adjust movement
-
Reach target position
🤖 8. Linear vs Non-Linear Control
| Linear Control | Non-Linear Control |
|---|---|
| Simple equations | Complex equations |
| Easy to implement | Difficult to design |
| Less accurate | More accurate |
| Used in basic robots | Used in advanced robots |
🤖 9. Applications of Robot Motion Control
✔ Industrial automation
✔ Medical robots
✔ CNC machines
✔ Space robots
✔ Autonomous vehicles
📌 EXAM IMPORTANT QUESTIONS (UNIT 4)
✅ Explain robot motion
✅ Lagrangian formulation
✅ Types of actuators
✅ Sensors used in robots
✅ Open vs closed loop control
✅ Motion conversion methods