• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer
  • Advertise
  • Subscribe

Motion Control Tips

Automation • Motion Control • Power Transmission

  • News
    • Industry News
    • Editor Blogs
  • Controls
    • HMIs
    • PC-Based Controllers
    • PLCs + PACs
    • Stand-Alone Controllers
    • Software
  • Drives
    • Servo Drives
    • Stepper Drives
  • Encoders
    • Absolute Encoders
    • Incremental Encoders
    • Rotary Encoders
  • Mechanical
    • Bearings
    • Brakes + Clutches
    • Belt + chain
    • Couplings
    • Gears + Gearing
    • Lubrication
    • Shock + Vibration Mitigation
    • Springs + Rings + Seals
  • Linear
    • Actuators
    • Linear Motors
    • Linear Encoders
  • Motors
    • AC Motors
    • DC Motors
    • Brushless Motors
    • Gearmotors
    • Piezo Motors
    • Servo Motors
    • Stepper Motors
  • Systems
    • Conveyors + linear transport systems
    • Gantries + Stages
    • Rotary Tables
    • Grippers + End Effectors
    • Robotics
  • Networks
    • Connections + Sliprings
    • Fieldbuses
    • I/O
    • Sensors + Vision
  • Resources
    • FAQs
      • Motion Casebook
      • Motion Selection Guides
    • Suppliers
    • Video
You are here: Home / Controls / What are Machine Controllers? Technical Summary for Motion Engineers

What are Machine Controllers? Technical Summary for Motion Engineers

October 6, 2011 By Motion Control Tips Editor Leave a Comment

In the most general sense, a controller receives some type of input and produces outputs for some device, most commonly an electric motor. More specifically, machine control, unlike a more specific type of controller such as a motion controller, refers to the control of an entire stand-alone machine such as a CNC machine, packaging machine, or even a vending machine.

The machine controller’s primary operations include scanning I/O, updating output and process control. After an initialization phase, the controller will continuously read inputs, calculate control parameters for the machine process using application-specific logic based on the input data, and then update outputs to the machine. If the controller is turned off, some shutdown process may be completed.

The central part of a machine controller is the controller itself, which can take on several forms. For single machine control, a programmable logic controller (PLC) or a programmable automation controller (PAC) is usually sufficient to handle the job. PLCs are usually programmed using ladder logic or sequential function charts. The controller receives various sensor data, processes this information and executes controls via some combination of digital and/or analog I/O signals to turn on or off processes, actuate or stop movement, and take user or environmental input and make decisions based on these inputs. Machine controllers will generally work together with some type of human-machine interface (HMI). These can be either integrated with the controller as one piece or can be stand-alone units that communicate with the controller.

More recently, machine control has seen a move to PACs because they can offer better performance and a wider range of functions than traditional PLCs. For instance, PACs can support high-speed data acquisition and processing, as well as motion control and vision functions.

In order to take advantage of all the features and capabilities of a PAC, the application code must be well designed, balancing and coordinating various controller processes such as I/O, process control logic, communication to an HMI unit and other tasks.

There are a number of considerations to keep in mind when selecting a machine controller. One of the most important is the number and type (i.e. analog or digital) of I/O the controller will have to handle. Also, do the speed requirements of the machine match up with the controller’s capabilities? For instance, some machine controllers may be tasked with closing servo loops and thus must be capable of handling such a task.

Another consideration is the type of communication link needed. The machine may have special demands or may be wired to accommodate a specific networking protocol, so ensure that the controller can communicate with the machine. Related to the communication link is the programming environment. Is the controller simple to program? Can programs be edited quickly and easily? Lastly, consider any environmental factors in which the machine will have to operate such as shock and vibration, extreme temperatures, and moisture or humidity.

You Might Also Like

Filed Under: Controls, FAQs + basics, PLCs + PACs Tagged With: machine controller, pac

Reader Interactions

Leave a Reply

You must be logged in to post a comment.

Primary Sidebar

LEARNING CENTER

Design World Learning Center

Motion Control Handbook

“mct
EXPAND YOUR KNOWLEDGE AND STAY CONNECTED
Get the latest info on technologies, tools and strategies for Design Engineering Professionals.

RSS Featured White Papers

  • Robotic Automation is Indispensable for the Logistics Industry’s Continued Growth and Success
  • Reliable Linear Motion For Packaging Machines
  • Polymers Outperform Metals In Precision Gearing

Footer

Motion Control Tips

DESIGN WORLD NETWORK

Design World Online
The Robot Report
Coupling Tips
Linear Motion Tips
Bearing Tips
Fastener Engineering.
Wire and Cable Tips

MOTION CONTROL TIPS

Subscribe to our newsletter
Advertise with us
Contact us
About us

Copyright © 2025 · WTWH Media LLC and its licensors. All rights reserved.
The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of WTWH Media.

Privacy Policy | RSS