National Instruments (NI) announced the release of the NI LabVIEW 8.5 Control Design and Simulation Module, an extension of the LabVIEW graphical system design platform that helps engineers and scientists analyze open-loop model behavior, design closed-loop controllers, simulate systems and create real-time implementations. The latest version of the module introduces new design features such as analytical proportional integral derivative (PID) for improving system closed-loop stability and model predictive control to multivariable systems. The LabVIEW Control Design and Simulation Module also offers expanded support of LabVIEW MathScript with the addition of 18 new .m file functions to simplify such tasks as creating models, defining how models are connected and analyzing system stability.
"The LabVIEW Control Design and Simulation Module significantly reduced the time it took us to develop the dynamic positioning on a split hopper vessel," said Miguel Taboada, control engineer with SEAPLACE, an offshore and naval engineering company in Madrid, Spain. "The module made it easy for us to simulate our different control algorithms and test the code without the use of any hardware. When we achieved the results we wanted in simulation, we were able to reuse the graphical code created with the module and deploy it to real hardware and debug it - all within a single day."
A new time-saving feature in the LabVIEW Control Design and Simulation Module is analytical PID capability. Historically, engineers and scientists have identified the proper PID controller gain values by experimentally tuning their controllers. The analytical PID feature provides engineers and scientists with functions to find sets of PID gain values automatically for a given system model, making it easy for them to avoid undesired behavior at design time and improve system stability.
The latest version of the module also includes model predictive control (MPC), a popular algorithm used in industry to control multiple input, multiple output (MIMO) systems in complex process control applications. Engineers and scientists can use the MPC feature to construct controllers that adjust the control action before a change in the output setpoint actually occurs. This ability to predict model behavior combined with traditional feedback helps the controller make smoother adjustments that are closer to the optimal control action values.
"Model predictive control is a valuable technique for industry that may not be so accessible to engineers unfamiliar with text-based programming," said Michael Grimble, technical director of ISC Ltd. and professor of industrial systems at the Industrial Control Centre at the University of Strathclyde in Glasgow, Scotland. "By adding MPC functionality in the LabVIEW Control Design and Simulation Module, National Instruments is providing a very intuitive tool with a simple real-time implementation interface. This should deliver tremendous benefits to engineers performing process control or machine control applications in industries such as automotive and aerospace, and even in academia where predicting model behavior is often a crucial step when developing advanced controls."
The LabVIEW Control Design and Simulation Module easily integrates with NI software tools such as the LabVIEW Statechart Module for event-based control design or simulation and the LabVIEW Real-Time Module for rapid control prototyping and hardware-in-the-loop applications as well as system deployment. Engineers and scientists also can combine the module with the LabVIEW System Identification Toolkit and NI I/O devices to develop reliable measurement-based controllers.
For more information on the LabVIEW Control Design and Simulation Module, visit www.ni.com/embeddedcontrol
Commentary By Jeffrey Rowe, Editor
This announcement by National Instruments reinforces the increasing need for simultaneous simulation of mechanical and electrical systems, also known as mechatronics. There was a time when mechanical systems and products were strictly mechanical, however, the majority of today’s products continue to become more capable, and more complex, involving the marriage of mechanical and electrical subsystems.
A more comprehensive way to view mechatronics is the systematic integration of mechanical, electrical, electronics, and embedded firmware (software) components. When all of the various components are combined the result is an electromechanical system. In this context, mechatronics is characterized by software and electronics controlling electromechanical systems. This definition is widely seen in automotive engines and other automotive systems, as well as production machinery.
Mechatronics can also be a method used for achieving an optimal design solution for an electromechanical product. Key mechatronics ideas are developed during the interdisciplinary simulation process that provide the conditions for fostering synergy for discovering solutions to complex design problems. The synergy arises from the integration of mechanical, electrical, and computer systems with information systems for the design and manufacture of mechatronics products. In other words, many different distinct subsystems coming together to perform a complex function. Mechatronic products exhibit performance characteristics that were previously difficult or impossible to achieve without a synergistic approach by applying information systems to mechanical, electrical, and computer systems.
A prominent trend is that as mechatronics systems get more complex and as functionality demands increase, in many instances software and firmware are replacing or at least supplementing hardware. A benefit of this transition from hardware to the burgeoning emphasis on software is called “postponement,” that is, the ability to include or change major functionality features during the final stages of production via embedded software.
As mechatronic systems get more complex, the challenges associated with successfully designing and executing them also become more demanding due to the interoperability requirements between electronic CAD (ECAD) and mechanical CAD (MCAD) software.
Mechatronics systems present major design and production challenges because they bring together many different types of physical and digital parts, processes, and personnel to create a successful end product. Designing and producing a mechatronics system requires a well-orchestrated effort by a wide variety of job roles and functions – everything from industrial design to PCB layout to control logic design to production planning.
There are several positive effects of integrating digital simulation and modeling in designing mechatronics, and for good reason – it saves time and money, reduces risk, and results in higher quality, more innovative products. Several of the 3D MCAD packages and the mechatronics synergy is the result of working with companies such as National Instruments. This synergy between the companies has resulted in the greatest value being realized in moving from mechanical to electromechanical machine design. Customers have benefited by integrating simulation and controls with the help of National Instruments (with products such as LabVIEW) and 3D modeling and mechanical analysis/simulation.
In the past, simulating the performance of a machine containing both mechanical and electrical components was a difficult and time-consuming process that required skilled specialists. Today, mechatronics design tools from National Instruments and several of the MCAD vendors are bringing the electrical and mechanical worlds together to make simulation and subsequent design easier. With 3D CAD, mechanical engineers can design machine parts and assemblies using a familiar interface with 3D visualization, while also simulating mechanism motion through mechanism dynamics.
While motion analysis packages are well-suited for open-loop motion simulations, a typical electromechanical system involves closed-loop control. For a true closed-loop simulation, engineers need to simulate not only the dynamics of a mechanism but also the controls that act on that mechanism. The LabVIEW interface for mechanical analysis packages provides an interface between the two environments so engineers can simulate closed-loop control for complex electromechanical systems. Closed-loop simulation between mechanical and control development environments can help drive better design decisions for both the mechanical and control aspects of a design.
Closed-loop simulation with a control design environment, such as LabVIEW, and a mechanical design environment, can help accelerate the design process for complex mechatronics systems, resulting in superior products in less time.
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Autodesk Announces Brazilian Synchrotron Light Laboratory as 2007 Inventor of the Year
Autodesk announced that the Brazilian Synchrotron Light Laboratory (LNLS), a research facility operated by the Brazilian Ministry of Science and Technology, has been named as the Autodesk Inventor of the Year for 2007. Nominated as Inventor of the Month for May 2007, LNLS was selected by members of the Autodesk manufacturing community who logged onto the Autodesk community web site ( http://mfgcommunity.autodesk.com) and voted for the 2007 Inventor of the Year. As one of approximately 50 synchrotron light laboratories in the world, LNLS allows a broad range of scientists to use powerful X-ray and ultraviolet beams to gain new insights into the atomic and molecular structure of various materials. By using Autodesk Inventor software, LNLS was able to design the Elliptically Polarizing Undulator (EPU), which featured nearly 15,800 parts divided into 5,560 standardized machinery elements, with 453 non-repeated parts inside the assembly.