A Textbook of Robotics 2

ONE Components of Robotic Systems.- General.- Mechanical Arm.- End Effector.- Robot Motors.- Computer (Controller).- Sensors.- Two The Mechanical Arm.- Mechanical Arm Structure.- Classifying Robots.- Cartesian Robots.- Cylindrical Robots.- Spherical Robots.- Horizontal Articulated Robots.- Vertical Articulated Robots.- Structural Characteristics of Robots.- Mechanical Rigidity.- Effects of Structure on Control.- Effects of Structure on Work Envelope and Work Volume.- Cartesian Robot Work Volume.- Cylindrical Robot Work Volume.- Spherical Robot Work Volume.- Horizontal Articulated Robot Work Volume.- Vertical Articulated Robot Work Volume.- Robot Work Volumes: Comparison.- Work Volume in Theory and Practice.- Advantages and Disadvantages of Various Kinematic Structures: Summary.- Open and Closed Kinematic Structures.- Wrist Joints.- Three Fundamental Concepts of Control.- Control Systems.- Open-Loop Control.- Closed-Loop Control.- Negative and Positive Feedback.- Control System Errors and Stability.- Transient and Steady State Response.- Stabilization and Servo Systems.- Loading Error.- Controller Types.- Proportional Control.- Integral Control.- Proportional-Integral Control.- Differential Control.- Proportional-Differential Control.- Proportional-Integral-Differential Control.- Four Electrical Drive Components.- DC Servo Motors.- DC Motor Structure.- The Motor as a Generator.- Opposite EMF in DC Motors.- Classifying DC Motors by Excitation Type.- Linear Regulation of Rate of Revolution in DC Servo Motors.- Pulse Width Modulation Control.- Stepping Motors.- Stepping Motor Controllers.- Stepping Motor Structure.- Stepping Motors: Summary.- Considerations in the Use of Stepping Versus DC Servo Motors.- Advantage of DC Motors.- Disadvantage of DC Servo Motors.- Advantage of Stepping Motors.- Disadvantage of Stepping Motors.- Five Hydraulic Drive Systems.- Properties of Hydraulic Fluids.- Analogies between Hydraulic and Electrical Parameters.- Principle of the Hydraulic Amplifier.- Reduction of Pressure Using a Venturi Tube.- Cylinders.- Cylinder Structure.- Piston Motion.- Piston Rate of Motion.- Selecting the Appropriate Cylinder.- Power Sources.- Gear Pump Structure and Principles of Operation.- Radial Hydraulic Motors.- Valves.- Directional Control Valves.- Regulating Valves.- Electrohydraulic Servo Valves.- Servo Valve Structure and Principles of Operation.- Six Feedback Devices.- Potentiometers.- Optical Encoders.- Resolution.- Range.- Absolute Position Encoder.- Incremental Position Encoder.- Computing the Resolution of Incremental Position Encoders.- Measuring Rates of Revolution Using Incremental Position Encoders.- Increasing the Resolution of Incremental Position Encoders.- DC Tachometers (Tachogenerators).- Seven Drive and Control Systems: An Appraisal.- Automatic Drilling Process: Computerized Control System for One Axis.- Operating Description.- Automatic Command for Filling Containers with a Constant Powder Volume.- Computer-Controlled System for Hydraulic Cylinder Position and Velocity Control.- System Description and Component Functions.- System Characteristics.- Description of Operation.- Hydraulic Cartesian Robot with Three Degrees of Freedom.- Eight Robot Path Control.- What is Path Control?.- Point-to-Point Control.- Point-to-Point Control: Summary.- Continuous Path Control.- Continuous Path Control Computations.- Joint Coordinate System.- World Coordinate System.- Tool Coordinate System.- Conversions within Systems.- Extracting Joint Variable Values for Robots with Two Degrees of Freedom.- Extracting Joint Variable Values for Robots with Three Degrees of Freedom.- Continuous Path Control in Practice.- Nine A Case Study.- Defining the Task.- Can this Robot Perform this Task?.- Do the Robot’s Degrees of Freedom Enable it to Carry out the Task?.- Can the Robot Motors Move the Arm and the Payload?.- Is the Accuracy Achieved by the Robot Suitable to the Accuracy Requirements of the Task?.- Operation of the Robot Components during Execution of the Assigned Task.- Will the Motor Stop at that Point?.- What kind of Controller is Used in this Control System?.