Chapter 1 Introduction § 1.1 Essential Concepts § 1.2 Scope § 1.3 History and Development § 1.4 Research and Development
§ 1.1 Essential Concepts (1) Subject and Relation Subject of Statics: Mainly concern on equilibrium Subject of Dynamics: Mainly concern on states evolution
§ 1.1 Essential Concepts (2) Structure of System Control Key words: command response control state communication controller plant system environment disturbance command response Liberation of Mechanical Control Decomposition of signal and power in mechanical control system through electronics (vacuum tube, transistor, OP,……)
§ 1.1 Essential Concepts (3) Ex: Computer Architecture
§ 1.1 Essential Concepts (4) Automatic derived from the Greek “Automatos” means by its own movement Described by Mathematics Statics: , if linear function (six equilibrium eqs in space) Dynamics: , if linear function (six D.O.F. in space) Control: , if linear function control dynamics Output: , if linear function
§ 1.1 Essential Concepts (5) States Evolution States of Mechanical System: (position), (velocity) Controller and System Dynamics Plant: , Additive control: Control action: New dynamics: Output response:
§ 1.1 Essential Concepts (6) Control and Decision Making Control is an objective-oriented decision making process.
§ 1.2 Scope E: electrical H: hydraulic (pneumatic) M: mechanical E-H H-M E-M servo servo mechanism servo control closed-loop control control system artifact system ecological system E: electrical H: hydraulic (pneumatic) M: mechanical Servomechanism: position control Control system: automatic control – closed loop automation – open loop
§ 1.3 History and Development (1) Technological development
§ 1.3 History and Development (2) Theoretical development Maxwell (1868): On Governor Lyapunov (1907): Problème général de la stabilité du mouvement Minorsky (1922): Directional Stability of Automatically Steered Body Nyquist (1932): Regeneration Theory
§ 1.3 History and Development (3) Mechanical Control Evolution
§ 1.3 History and Development (4) James Watt A letter to Boulton and Watt 1789, Peter Drinkwater: The governor is of a nature solely calculated to secure more effectually an equable motion under different degrees of heat from the fire,……
Original Script (governor, throttle valve, and connexions 1798) § 1.3 History and Development (5) Watt’s Flyball Governor Original Script (governor, throttle valve, and connexions 1798)
§ 1.3 History and Development (6) Operation principle: It measured the speed of the output shaft and utilized the movement of the flyball with speed to control the valve and therefore the amount of steam entering the engine. As the speed increases, the ball weights rise and move away from the shaft axis thus closing the valve.
§ 1.3 History and Development (7) Dynamics
§ 1.4 Research and Development (1)
§ 1.4 Research and Development (2) Hadware and Software in Automatic Machinery command response Actuator- a device that converts energy into mechanical motion Sensor- a device that detects and responses to specific input(s) from the physical environment
§ 1.4 Research and Development (3) Automatic Machinery Industry
§ 1.4 Research and Development (4) Technical Systems