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

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

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

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

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

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

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

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 Can not 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 temperature sensed 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 (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. Closed Loop 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 report a closed condition and turns off the light – feedback is present. Another example is a thermostat. Heating or cooling equipment is actuated based on temperature sensed. Project Lead The Way, Inc. Copyright 2008

Image Resources Microsoft, Inc. (2008). Clip Art. Retrieved from http://office.microsoft.com/en-us/clipart/default.aspx