1. Control Systems An Overview Computer Integrated Manufacturing
© 2013 Project Lead The Way, Inc.

2. Control Systems
CIM
Control Systems
Definition
A control system is a device or set of devices that are coordinated to execute a planned set of actions.
A control system can be huge, as in a set of computers controlling a factory operation, or it can be small, as in a light switch.
Project Lead The Way, Inc.
Copyright 2008

3. Video Game Controller Remote is handled by user (you)
Control Systems
CIM
Control Systems
Video Game Controller
Remote is handled by user (you)
Input is sent to game console and processed
Output / data is sent to monitor
Feedback appears on screen
Output is viewed as visual feedback
All video game controllers are control devices, whether wired or wireless. In both instances, objects on a monitor are manipulated through the use of the device.
Xbox 360 controller shown here.
Project Lead The Way, Inc.
Copyright 2008

4. How Video Game Controller Works
Control Systems
CIM
Control Systems
How Video Game Controller Works
Input
Input
Processing
Device is
manipulated
Sensor read
Reading
processed
Feedback
on monitor
Game
responds
Although the diagram here is in a loop, a control system does not have to be a loop. For example, you may use a remote to turn on your television. Once the television is on, you may not use the control device again.
Output
Output
Input Process Output
Feedback
Typical Closed Loop Process
Project Lead The Way, Inc.
Copyright 2008

5. Music Player What is the input for increasing the volume?
Control Systems
CIM
Control Systems
Music Player
What is the input for increasing the volume?
What is the process?
What is the output?
What is the feedback?
Feedback comes in many forms. It can be the volume, bass, treble, song choice, display, or a variety of other outputs.
Project Lead The Way, Inc.
Copyright 2008

6. Music Player Controls operated by user and signals sent to device
Control Systems
CIM
Control Systems
Music Player
Controls operated by user and signals sent to device
Request is processed by device and desired conditions are set
Volume strength is increased
Feedback is heard through headphones by user
Feedback comes in many forms. It can be the volume, bass, treble, song choice, display, or a variety of other outputs.
Project Lead The Way, Inc.
Copyright 2008

7. Typical Closed Loop Process
Control Systems
CIM
Control Systems
How It Works
Device is
manipulated
Sensor read
Reading
processed
Feedback
through
headphones
Player
responds
Again, the control system does not have to be cyclic, but it can be.
Typical Closed Loop Process
Input Process Output
Feedback
Project Lead The Way, Inc.
Copyright 2008

8. Open and Closed Loop Open Loop Control System
Control Systems
CIM
Control Systems
Open and Closed Loop
Open Loop Control System
Sprinkler System
No direct connection between the output of the system and the conditions can be controlled
Cannot compensate for unexpected forces
Closed Loop Control System
Refrigerator Light Sensor
Provides the system with operation feedback
Can compensate for conditional changes
Thermostat
Heating or cooling equipment is actuated based on the temperature sensed
An Open Loop example is a sprinkler system. A sprinkler system is on a timer; it will turn on at a given time if no moisture sensors are in place to tell the system the water is not necessary (e.g., it is raining). The timer is also on an open loop. If the water has been turned off and no sensors or feedback are present, the timer will turn on the pumps and attempt to run the process regardless.
A Closed Loop example is a refrigerator light sensor. When the door opens, the door sensor reports an open condition and turns on the light. When the door is closed, the sensor reports a closed condition and turns off the light—feedback is present. Another example is a thermostat. Heating or cooling equipment is actuated based on the temperature sensed.
Project Lead The Way, Inc.
Copyright 2008

9. Image Resources
Microsoft, Inc. (2008). Clip Art. Retrieved from