Technology inside: Bacon slicer motion control

The Delta motion controller is programmed to do closed-loop position control using encoder feedback from the servo drive that moves the bacon slab into the cutting blade. The RMC sends a +/- 10 V analog output to the servo drive that moves the bacon slab.

10/29/2012


Figure 2. The RMC75E motion controller from Delta Computer Systems controls up to two motion axes simultaneously. Courtesy: Delta Computer SystemsTo improve the performance of the bacon slicer, Titan Slicer executives called in an experienced control system integrator, Tui Technology of Rotorua and Whangarei, New Zealand. Tui’s engineer, Malcolm Jones, had worked with motion controllers made by Delta Computer Systems Inc. of Battle Ground, Wash., in the past and came up with a new control system design for the bacon slicing machine using a Delta RMC75 motion controller. A PLC was still used in the new design, but for less time-critical functions, such as issuing on/off controls for the blade motor.

The Delta motion controller is programmed to do closed-loop position control using encoder feedback from the servo drive that moves the bacon slab into the cutting blade. The RMC sends a +/- 10 V analog output to the servo drive that moves the bacon slab.

The RMC’s fast cycle time allows the cutting operation to produce repeatable results. At 1600 rpm, there is a 38 ms time window in which to decide whether the bacon slab is to be moved forward to set up for the next cut or backward to clear the blade. The 1 ms loop time in the RMC running the Advanced Gear Move instruction enables repeatable and accurate slice thickness.

The Advanced Gear Move is just one of a number of gearing functions supported by the RMC 75. Whereas simple linear relationships can be set up between master and slave (using the RMC’s Gear Absolute function), an Advanced Gear Move operation lets the user program a nonlinear relationship between master and slave. For example, Figure 4 shows an Advanced Gear Move operation where the motion of the slave is dictated using a fifth-order polynomial equation. Most of the RMC’s simpler gearing commands allow the designer to choose the exact gear ratio to be used by specifying a numerator and denominator when the motion step is programmed.

Malcolm Jones said, “Where the RMC pays for itself is in the control of the first slice to meet our critical design goal.”

To program and tune the motion, Malcolm Jones used Delta Computer Systems’ RMCTools software, which includes a Plot Manager that displays trend or capture plots for key motion parameters versus time. Figure 4 is a plot that was produced by the Plot Manager that shows the operation of the advanced gear move instruction. RMCTools software also includes a Tuning Wizard, which enables quick and easy setting of control loop parameter gains for optimizing motion. “Using the Delta tools, I was able to prove that the system had enough timing margin to handle the higher cutting speeds,” said Jones.

www.deltamotion.com 

- Brad Smith is regional applications specialist, Delta Computer Systems Inc. Edited by Mark T. Hoske, content manager CFE Media, Control Engineering and Plant Engineering, mhoske@cfemedia.com.



No comments
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Additive manufacturing benefits; HMI and sensor tips; System integrator advice; Innovations from the industry
Robotic safety, collaboration, standards; DCS migration tips; IT/OT convergence; 2017 Control Engineering Salary and Career Survey
Integrated mobility; Artificial intelligence; Predictive motion control; Sensors and control system inputs; Asset Management; Cybersecurity
Featured articles highlight technologies that enable the Industrial Internet of Things, IIoT-related products and strategies to get data more easily to the user.
This article collection contains several articles on how automation and controls are helping human-machine interface (HMI) hardware and software advance.
This digital report will explore several aspects of how IIoT will transform manufacturing in the coming years.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Infrastructure for natural gas expansion; Artificial lift methods; Disruptive technology and fugitive gas emissions
Mobility as the means to offshore innovation; Preventing another Deepwater Horizon; ROVs as subsea robots; SCADA and the radio spectrum
Future of oil and gas projects; Reservoir models; The importance of SCADA to oil and gas
Automation Engineer; Wood Group
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me