Real-time ethernet lets stitcher heal itself

Dec. 8, 2005
A real-time motion-control network based on the physical layer of Ethernet, called SynqNet, let a printing and converting manufacturer devise a stitching machine that can "heal" itself if one of its stations go down.

Real-time Ethernet lets stitcher heal itself

The Pacesetter 1100 (above) uses a synqNet network with Digiflex Series SynqNet drives from Advanced Motion Controls, customized to include additional I/O. They drive motors from Baldor Electric Co.


 

The Pacesetter 1100 from Goss International Americas Inc., Durham, N.H., is a saddle stitcher that assembles pages of a magazine in the right order, staples them together, and then trims the edges before delivering finished publications for stacking. The old way of powering saddlestitching machines was with a 40-hp motor and mechanical driveshaft with take-offs for each section. Moving the saddle stitcher to a servodriven-feeder approach allows the same advantages as seen in other kinds of printing equipment that have changed over to servos: dynamic on-the-fly adjustments, less make-ready time and changeover time between jobs, and tight synchronization between operations.

Goss Senior Project Engineer Atef Massoud evaluated nine different motion-control systems for the machine before settling on a SynqNet control platform from Motion Engineering Inc., Santa Barbara, Calif. This highspeed networking scheme, basically a real-time implementation of Ethernet, can handle servocycle update rates to 8 kHz for 20 axes connected to a SynqNet stand-alone controller. In particular, the network let Goss architect the machine with self-healing fault tolerance, a quality unavailable in the other networks Massoud evaluated. The network is configured in a ring topology so if one or more stations are off-line the rest can continue operating without stopping the line. The reason is the self-healing mechanism uses the redundant link on the fly.

Software utilities from MEI also aided in the development of a customized velocity feedforward algorithm for the machine. The master axis drives a chain which moves the magazine sections, called signatures, through the line of feeder stations to stapling and trimming operations. The motor drive for the chain sends incremental encoder data out over SynqNet, where it is used as the master axis to create position and velocity commands for the respective axes to calculate commands for the servos. In Pacesetters that have more than 20 feeder stations, a second SynqNet is used to handle the additional modules. In this case, the master encoder signal is split and sent to the master axis for each of the two SynqNets.

Software tools from MEI facilitated frequency response analysis, allowing designers to shape the frequency response while maintaining desired stability margins.

About the Author

Leland Teschler

Lee Teschler served as Editor-in-Chief of Machine Design until 2014. He holds a B.S. Engineering from the University of Michigan; a B.S. Electrical Engineering from the University of Michigan; and an MBA from Cleveland State University. Prior to joining Penton, Lee worked as a Communications design engineer for the U.S. Government.

Sponsored Recommendations

The entire spectrum of drive technology

June 5, 2024
Read exciting stories about all aspects of maxon drive technology in our magazine.

MONITORING RELAYS — TYPES AND APPLICATIONS

May 15, 2024
Production equipment is expensive and needs to be protected against input abnormalities such as voltage, current, frequency, and phase to stay online and in operation for the ...

Solenoid Valve Mechanics: Understanding Force Balance Equations

May 13, 2024
When evaluating a solenoid valve for a particular application, it is important to ensure that the valve can both remain in state and transition between its de-energized and fully...

Solenoid Valve Basics: What They Are, What They Do, and How They Work

May 13, 2024
A solenoid valve is an electromechanical device used to control the flow of a liquid or gas. It is comprised of two features: a solenoid and a valve. The solenoid is an electric...

Voice your opinion!

To join the conversation, and become an exclusive member of Machine Design, create an account today!