Motion Control Roundtable ’08
By Mike McLeodMotion Control commentary roundtable
Industry leaders discuss trends in motion control
DE: Given present economic conditions, where reducing costs and development time are paramount, why should manufacturers take the risk of adopting new technologies?
Joe Ottenhof, Regional Manager, Beckhoff Automation Canada: I think it’s really a matter of survival. The adoption rate of new technologies in EU countries and Japan is noticeably better than in North America because there is a mentality of fear here, not only in terms of what it means in costs but in people’s skill sets. And yes, it can be painful, but overall, adopting new technologies, while managing the risks associated with them, not only lowers product costs, it shifts skill sets. The result is that productivity rates go up and domestic jobs are saved. Beckhoff is a classic example. We design and build everything we make in Germany, hardly a low-cost centre in the world, and yet we are growing market share while developing innovative and leading-edge technologies
Anthony Morielli, Product Manager, Electric Drives and Controls, Bosch Rexroth Canada: For Canadian manufacturers in particular, we are competing in a global marketplace, so it is no longer good enough to supply a machine at the lowest cost. Now, you have to supply a machine that has all the features and technology available at a competitive price. Adopting new technology not only gives you more capabilities but also helps you reduce costs without sacrificing machine performance and may potentially improve it.
Doug Pike, District Manager, Danaher Motion Canada: Canadian OEMs have to become more productive and more efficient in building these machines to offset the higher Canadian dollar. Sure, there is a risk to adopting new technology, but that can typically be worked out during the prototyping phase. And most of the new technology in the motion control field is not light-years ahead. It’s simply the next generation and backward compatible with the generation before them. As manufacturers, what we are trying to do is reduce the possible risk so that customers do buy in. The benefits are higher bandwidth, higher throughput, higher efficiencies and higher productivity in their machines—all qualities that can set them apart from their competition in the U.S.
John Pritchard, Product Marketing Manager, Kinetix Motion Control (Rockwell): Reducing costs is always on the mind of machine builders. We focus on reducing the total cost of ownership, which includes reducing design cost and machine production time. One example is to apply motion control in a way that helps increase machine flexibility and improve performance. So rather than making 100 parts per minute, you are making 160 with a shorter product set up time, and that changes the formula in terms of what the machine is worth. I think there is risk in any new technology, in fact in any new design, but there are ways to mitigate that if you use the tools that are available.
Goran Tesanovic, Manager – Motion Control, Siemens Canada: Adopting new technologies is a must. Otherwise, manufacturers will be outperformed by their competition and disappear. Just look at what happened to those who relied solely on a low Canadian dollar without factoring in continuous improvements and new technologies.
DE: Which products or technologies are your customers overlooking, ignoring or unaware of, to their detriment?
Beckhoff/Ottenhof: What people are missing is that fast I/O technology is applicable even to slower machine types because cycle time is the single most important measurable factor in manufacturing, whether you’re making a car or a hinge. What many companies forget is that microseconds saved on every operation may lead to, over the course of a day, 50 or 1,000 seconds, which may result in a four or five-percent improvement in cycle time. What we are trying to do is provide a fast enough control system at a low cost so that the control system itself is never a constraint. Instead, the constraint is the mechanical and electrical limits of the machine itself.
Morielli/Rexroth: One area being overlooked is decentralized control. Typically, a main controller, either a PLC or PAC, controls the overall machine, but it is now possible to have control at the drive level. While it may not be appropriate for all applications, decentralized control can result in significant cost savings and faster performance because the control is inside the drive. The communication between the control and the drive is instant, which can result in higher cycle times and reduce the number of external components as well. So if you eliminate the external PLC or PAC controller and all the associated I/O and you have all that inside the drive, you have more space inside your cabinet and all the wiring between the drive and the control system is gone.
Pike/Danaher: In Europe, there is more of a software-based push with new communication busses to adopt the I/O control. For example, our Danaher Motion Suite, which directly links all three main functions of a control system—collection and monitoring of process machine data, PLC and motion control—in a common development and software environment, has been very popular there. It will be a while before that move takes hold here, because there is such an install base of PLCs and people are shy about moving to an operating system platform. But there are more robust and stable operating system platforms, and I think people will begin putting more faith into software-based machine control.
Pritchard/Kinetix: What customers may be overlooking isn’t so much a product as a design method or workflow. By taking a holistic or what we call a mechatronic view, machine builders can make significant improvements to their machine’s throughput, accuracy, energy consumption and even its reliability. For this, we have a specific tool called Motion Analyzer, which is a free software tool we use to analyze and optimize customer machines. In conjunction with an MCAD package like SolidWorks, Motion Analyzer can not only help customers properly size and select components but also help optimize a motion profile and run tuning simulations. Because most of the trial and error is done virtually instead of on the factory floor, in the long run it’s quicker and cheaper, with the added bonus that you have a high confidence the machine will work the first time.
Tesanovic/Siemens: Customers may be unaware of the benefits of integrating motion control and logic control in one system and, therefore, two programming software packages in one environment, all of which is possible using the Siemens SIMOTION platform. The advantages are huge and include faster training, minimal engineering efforts and higher productivity. SIMOTION’s Integrated Web server functionality is a perfect example. With it, users can perform machine upgrades, software updates, alarm monitoring and acknowledging, as well as gathering controller diagnostic information without being on the machine.
DE: How is your company making system programming faster/easier?
Beckhoff/Ottenhof: Faster and easier? On one level, some would say not much, but on another level we would argue we’ve done a tremendous amount. Let me explain. Beckhoff has adopted and is committed to the IEC 6-1131 standard for automation programming for both logic and motion applications. This standard is continually evolving to reflect best practices in automation. However, for most PLC programmers in N.A., it would be fair to say that “1131” is not an intuitive or easy environment to work in. The learning curve compared to a graphical ladder logic editor is significant. However, the standard promotes a high degree of code reusability, structure and f
lexibility, similar to what you might get in a computer-programming environment such as C++. That, in turn, promotes “faster and easier” code generation.
Morielli/Rexroth: In the last couple of years, motion and logic have been integrated into the programming language standard IEC 6-1131 overseen by the OpenPLC organization. The overall vision for IEC 6-1131 is to eventually take code from one supplier and dump it into another, but the standard isn’t quite there yet. Until then, we are helping to simplify the programming process by developing function blocks for the specific industries we target. For metal forming, for example, we have function blocks for flying cut-off or roll-feed applications. We also have entire sample programs written for pick-and-place robotic applications and a library of more than 100 kinematic equations for high-end robotics.
Pike/Danaher: With every generation of new drives, we try to make the programming easier. So the GUI, through successive generations, gets more user-friendly. You would find the same with any company doing strict motion control. We all have our own software programs and have spent great deal of time and resources to making sure that it is a selling feature so we can walk into an OEM and say, “You know what, this shows up on your dock, you plug it in and 20 minutes later your machine is spinning.” While that works for about 80 percent of applications, there is still the other 20 percent that need much more detailed motion control and the expertise of our distributors or our technical support.
Sandy Holden, market development manager, Rockwell Automation: We’ve spent a lot time developing modular code that allows users to have the same common look and feel across their entire enterprise. So whether you are a process or discrete machine builder, we are developing a common set of programming modules or blocks under the ANSI/ISA-88 model, which is emerging as a common standard across the industry. As such, when you go to configure a machine, it is much quicker to do, and you can do it repeatably so you have fewer errors.
Tesanovic/Siemens: The SIMOTION system is designed with ease-of-use in mind. First, in SIMOTION, motion control software and logic control software are integrated in one easy-to-use programming language / environment. It saves time and eliminates the need for training on two platforms (languages). Second, SIMOTION comes with huge library of ready-to-apply solutions like winder, rotating knife, cut-to length, roll-feed, transfer, print mark registration, tension control, electronic coupling, etc. All those solutions are preprogrammed by technology experts, tested, proven in the field, ready for programmers to use and save time, money and remove risk of a new, untested design.
DE: What should companies keep in mind when implementing or upgrading an integrated safety system?
Beckhoff/Ottenhof: You have to be aware of the legislation affecting your facility and equipment because, in Ontario particularly, safety is a moving target at this point anyway. Beyond that, you should look at programmable safety very carefully. Many applications that traditionally used safety relays can now use programmable safety for the same cost or close to it. The resultant flexibility and added diagnostics pay for themselves quickly through avoidance of nuisance trips and the ability to rapidly isolate intermittent device failures. In motion applications, use drive technology with integrated safety capability. This provides a significant reduction in complexity while providing a level of operator/machine interaction that enhances productivity without compromising safety.
Morielli/Rexroth: One thing we keep reminding customers is that drive-based safety is probably the safest way of monitoring motion control-based applications. If you look at the statistics for safety-related incidences, serious issues usually occur during setup or change over when an operator gets near the machine to jog it at a slow speed or there is a jam and they have to open a safety gate. With drive-based safety, operators can still get close, but they can’t bypass any safety circuits. The machine will always be in safe mode. In the past, people had the impression that making the machine safe would also make it more expensive. Now the technology is enabling them to have some high-end safety functions without necessarily increasing machine costs and may actually reduce the costs because you have reduced downtime and accelerated recovery time.
Pike/Danaher: As a company, Danaher doesn’t really get into safety in and of itself. But as we move toward PC-based software driven motion control applications, there are some safety standards that have to be met. In other words, when you are moving into a software, PC-based realm, safety becomes much more critical, because no longer can you just walk up to the drive and unplug it or whatever. You have to rely on the HMI and the software running the system.
Holden/Rockwell: Obviously, each machine is different, so the best and the most cost-effective approach is to get a risk assessment done up front. Another thing is that it looks as though EN 954-1 and IEC 61508 are going to be converging in the future to become an ISO standard: ISO 13849. This means that builders in the U.S. and Europe will have to meet that common assessment. Also, if you are considering implementing safety, and there are standard drives and motion involved, then make sure you look for a servo drive that has built-in safe torque off functionality because the wiring involved is dramatically reduced versus having to implement it using lots of extra contactors and breakers and the like.
Tesanovic/Siemens: When implementing integrated safety systems, companies should first perform risk analyses to determine the frequency of dangerous situations, probability of occurrence and chance to recognize impending danger. Safety Integrated solutions not only protect personnel and equipment more effectively but their application-focused functionality increases up time and productivity. With the trend toward modular machines, the move from centralized safety control down into the motion control system and drives allows the conditions around a specific task and area to be protected versus shutting down a complete machine. Integration brings simpler and faster ways of diagnosing the problem.
DE: In what ways is your company helping customers meet energy efficiency/environmental targets?
Beckhoff/Ottenhof: On the environmental side, the EU RoHS and WEEE directives are major driving forces for all EU manufacturers, including Beckhoff. As such, we are contributing to the reduction of lead in the environment, which is a major design thrust for us at this time. On the industrial side, as an example, we have new technologies for doing simple speed control on AC and DC motors. AC motors consume something like 12 percent of all power used in industrial marketplaces. So cost effectively, reducing the speed of an AC motor can have a tremendous effect on the overall use of energy. Also commercial energy management techniques common in building automation are having an impact in industrial workplaces as well.
Morielli/Rexroth: Customers haven’t specifically asked for it but, from our side, we have been coming up with technologies with energy efficiency in mind. For example, our modular drive systems share a common power supply, which can be sized according to all the axes connected to it. This allows greater use of power in the overall system rather than having individual drives with their own power supply. And if you have multiple axes, some motors may be doing work in motoring mode while other
motors are regenerating or sending their excess energy to the common DC bus for the motors in motoring mode to use. In addition, our hydraulics and electric drive departments have come up with servo-driven pumps that benefit from reduced energy consumption by bringing down the pump to a lower speed. At the same time, they don’t sacrifice performance and can quickly accelerate and achieve the high torques typically needed in hydraulic systems.
Pike/Danaher: There has always been a drive at Danaher and in the motion control industry to get smaller form factors to cut down on cabinet space while increasing the efficiency and productivity of every successive generation of controller. Before, everybody just wanted to make more widgets for every dollar they put in. Now with every dollar put in, more of that dollar is taken out by energy. With that in mind, our new Mako drives coming out later this year will feature a smaller form factor, industry leading power density and much better heat dissipation.
Holden/Rockwell: This is a factor that I think will ramp up rapidly. Companies like Wal-Mart, for instance, have been driving their vendors to supply their products more responsibly going forward, which includes improving machine performance and overall energy usage and carbon footprint. They even have report cards to measure that as one of the criteria for purchasing from a vendor. In response, we are focusing around energy efficiency for safety and reducing material waste in a lot of the systems and services we offer, whether it is for motion control or any other system.
Tesanovic/Siemens: There are two areas where Siemens drives are leading this: common DC bus systems and Active Front End units. With common DC bus drive systems, the customer can take advantage of power sharing across the bus between generating and motoring loads which lowers the overall power consumption. In addition, Active Front End units, with four-quadrant operation and lower harmonic generation, provide power-factor correction and generate power back into the grid.