Portland Community College | Portland, Oregon

Upon completion of the course students should be able to:

1. Identify the basic components of a modern control system.
2. Explain how these components work (e.g. describe how a stepper motor takes discrete steps or how pneumatic valves open and shut).
3. Perform simple calculations on the functionalities of these components (e.g. tell what resolution a 12 bit A/D converter gives; tell the temperature of a thermocouple reading from its voltage vs. temperature characteristics).
4. Build, in a laboratory setting, simple systems in which these components can perform their basic functions (e.g. use a computer to instruct a stepper motor to go 10 steps clock wise and 2 steps counter clock wise).
5. Build a simple system where the various components can work together to achieve automatic control (e.g. build a close loop control system with sensors, controllers and actuators to perform desired control tasks).

The course will include instructor delivered lectures and demonstrations stressing key topics in the course. Students will also reinforce and practice concepts learned in a laboratory setting.

Assessment of student performance in this course will be in the form of homework, quizzes, exams, in-class lab performance and lab reports.

REQUIRED STUDENT COMPETENCIES:

Chapter 1              Control System

Section 1         Control system

1                 Know that a control system is made of 3 major components: controller, sensors and actuators. Know the basic functions of these components and how together they can perform a control task.

2                 Be able to give examples of control system in daily life and in the fabrication.  Also be able to tell in such an example which part is the controller, sensor, or actuator.

Section 2         Controller

1                 Know commonly used controller types

2                 Know the advantage of micro-processor based controllers

3                 Know the major components of a micro-processor based controller: CPU, memory, I/O, and peripheral power supply.

4                 Know the types of micro-processor based controllers and their characteristics in terms of where the major components of the controllers are built into (CPU/Memory/IO on a chip vs. CPU/Memory/IO on a board, etc.)

5                 Be able to select the most suitable controller type based on the application.

6                 Tell types of controllers used in fab equipment.

Section 3         PC based controller

1                 Know major components of a PC and their basic functions: CPU, Memory, Bus, I/O and how signal travels among them

2                 Know commonly used bus and IO port types.

3                 Know necessary functions performed by the interface between PC and sensors/actuators.

4                 Know what components of the interface perform which functions above.

5                 Know the structure of the interface and how signals travel between controller and sensor/actuator.

6                 Be able to work out the above interface for a given control task.

7                 Know how the Daq card interface and GPIB interface relate to the above generic interface structure.

8                 In laboratory setting, assemble a basic Daq card interface to read and write multiple channel digital signals from/to a PC.

9                 In laboratory setting, assemble a basic GPIB interface to read single channel analog voltage signal as measured by a multi-meter into a PC.

Section 4         Control software

1                 Learn the basic elements of control software.

2                 Learn to write very basic control software programs in LabView.

Chapter 2              Signal Conditioning

Section 1         Explain types of signal conditioning needed for sensors: signal amplification, filtering, impedance isolation

Section 2         Op-amp

1                 Know circuit connection, amplification factor, equivalent input and output impedance of four types of op-amp circuits: Voltage follower, inverting op-amp, non-inverting op-amp, and differential op-amp.

2                 Explain how op-amps can be used to achieve signal amplification and the transformation from high impedance to low impedance signals. Know that op-amps are typically not used for power amplification of actuators.

3                 Be able to design a suitable op-amp circuit based on the amplification, impedance isolation, and polarity need of the application.

Chapter 5              DC motors

Section 5         DC motor control circuits

1                 Understand how to control motor direction and stoppage using circuits.

2                 Understand how to use analog drive to achieve motor speed control. Be able to do so in a laboratory setting.

3                 Understand how to use pulse-width-modulation to achieve motor speed control. Be able to do so in a laboratory setting.

Chapter 6              Stepper Motors

Section 1         Theory of operation

1                 Explain how stepper motors can take discrete steps

2                 Explain its advantages and disadvantages

3                 Understand the different characteristics and features of the speed vs. torque curve.

4                 Distinguish between slewing and single-stepping modes

Section 2         Excitation modes

1                 Understand excitation sequence of a two-phase vs. four-phase motor.

Section 3         How to achieve finer step size:

1                 Understand how finer step size can be achieved by multi-pole rotors, by multi-stack rotors, by variable-reluctance stepper motors, and by hybrid stepper motors.

Section 4         Stepper motor driver circuit

1                 Understand how 4-phase stepper motor control circuit works

2                 Understand how 2-phase stepper motor control circuit works

3                 Be able to control a stepper motor with a stepper motor control circuit connected to a PC in a laboratory setting.