New CNC kernel offers remarkable performance and flexibility for small to medium size machines

handles up to 5 axes, with dual channel capability for control flexibility

09/16/2013 – Teufen (AR), CH

NUM has extended its market-leading Flexium+ family of CNC kernels with a new hardware configuration option that provides machine tool manufacturers with a very cost-effective control solution for small to medium size machines.

Adding a mid-range option to NUM’s latest-generation CNC platform, the new Flexium+ 8 CNC kernel is designed specifically for machine applications that require movement of up to five axes. In terms of control flexibility it is comparable to NUM’s most powerful CNC kernel, the Flexium+ 68, and can be used with all Flexium+ compatible hardware and software.

The Flexium+ 8 CNC kernel offers two CNC channels and accommodates up to four simultaneously interpolated axes. It can also be configured to handle more complex types of interpolation such as Spline and NURBS (Non-Uniform Rational B-Spline), and offers various options and technology packages.

At any one time, either CNC channel can be used to control a spindle motor and four axes, instead of the full complement of five axes. This simplifies the design of complex machines with multiple synchronisation requirements by allowing easy control partitioning. For example, on a thread or gear cutting machine, one channel could control two axes and a spindle to perform the process functions, while the second channel could be used to control two feed axes. Each channel can run its own part program asynchronously and operate autonomously, much as if it had a dedicated CNC kernel. Or, the two channels can be synchronised. Control of one to five axes, or a spindle, can be passed on-the-fly from one channel to the other, to maximise use of available hardware resources.

Peter von Rueti, NUM’s CEO, points out that this control flexibility is a major advantage for many machine tool builders. “Flexium+ 8’s dual channel capability allows designers to implement extremely cost-effective control architectures for complex small to medium size machines. It will in many circumstances be able to eliminate the need for a second CNC kernel.”

Although the Flexium+ 8 CNC kernel can be used with various NUM drives, for optimum performance it is best teamed with the company’s latest NUMDrive X digital servo drive modules. These drives are some of the smallest on the market, and offer numerous configuration options, including outputs from a few amps to 200 Arms, single- and dual-axis versions, and a choice of basic and enhanced safe motion monitoring functionality. The drives are available in standard, high and enhanced performance versions, to help designers minimise machine build costs by using the optimum model for each axis of their application.

All NUMDrive X servo drive modules use advanced DSP control techniques to maximise the CNC kernel-to-drive servo bus speed, and feature high loop bandwidths and special acceleration algorithms for uncompromised speed and positioning accuracy. A numerical processor in the CNC kernel, together with the precision number-handling capabilities of Flexium+ software, helps ensure a high overall CNC resolution and facilitates extremely fine interpolation between axes. The drives accept virtually all types of measuring systems and can control a broad range of motors – including servo, torque, linear and asynchronous designs – from NUM or third-party manufacturers.

The high-performance version of NUMDrive X extends the capabilities of the standard version by allowing users to create Drive Embedded Macros (patent pending), known as DEM-X. These are real-time macros embedded within the drive, to interact with all physical and virtual drive resources. The macros even allow manipulation of the drive’s regulation algorithms for fine-tuning the speed, position and torque servo control loops. Users can design and implement filters, monitors, test points and pilot outputs which obey their own choice of performance rules.

NUM is launching the enhanced-performance (EP) NUMDrive X module at the same time as Flexium+ 8. Developed specifically for machine axes that require exceptionally high speed and acceleration capabilities, the new drive combines very high internal resolution with huge calculation power. By sampling at 40 kHz, it provides extremely wide current, speed and position loop bandwidths. The drives are particularly suitable for use where the overall performance of a machine is limited by the bandwidths of its servo systems, and not by its inherent mechanical design.

Flexium+ 8 features an inherently scalable safety architecture known as NUMSafe. A safety PLC built into the CNC system oversees all critical operations; in conjunction with NUM’s safe I/O modules and the safe motion monitoring circuits in Flexium+ drives, this enables machine designers to implement high-integrity safety functions using minimal additional components. The safety architecture complies with the EN ISO 13849-1 machinery safety standard up to PL e, as well as the EN 61800-5-2 functional safety standard for variable speed drives, up to SIL 3.

NUM’s Flexium+ CNC platform now includes three CNC kernels, enabling machine designers to configure cost- and performance-optimised control systems for a wide range of automation, from small machines with just a few axes to large multi-cell manufacturing equipment with over 200 axes and spindles. By adopting a common CNC platform for different projects, designers can lower their development and support costs significantly, and speed time to market.

The Flexium+ platform is backed by powerful software. All CNC, servo drive, I/O, automation PLC and safety PLC functions are programmed using a single unified toolset. A fully customisable HMI allows users to add value to their machines, through improved ergonomics and touch-sensitive controls. A powerful 3D graphical simulator operates interactively with the system’s CNC kernel, allowing part programs to be verified before use. NUM’s application support software covers a broad range of machining functions such as grinding, tool grinding, turning, milling, gear hobbing, shaping and finishing, as well as water-jet, laser  and plasma cutting. Many of these software packages are regarded by machine tool manufacturers – and users – as industry standards.

For machine designers who require the control flexibility of Flexium+ 8, but do not need extensive built-in safety functions, NUM is also introducing a hardware configuration option known as Flexium 8. This provides the same control functionality as the Flexium+ 8 system, but without the NUMSafe safety architecture.