NUM Flexium+ allows standardisation and optimisation of CNC architecture across many machine types

4 mins read

NUM's modular safety-equipped Flexium+ enables OEMs to standardise on a single cost and performance optimised CNC architecture for a wide range of machine types – from small machines with a few axes to large multi-cell manufacturing equipment with over 200 axes and spindles. In this way, the open architecture of the CNC platform can dramatically lower development and support costs, and speed time to market.

Flexium+ builds on the architecture of NUM's Flexium CNC to provide greater versatility, dynamic performance and accuracy. The platform's hardware includes digital servodrive modules with integrated safety, a safety PLC module, safe input and output modules, and a multi-processor operator panel with touch-sensitive screen. Support software includes a precision operating system and soft automation PLC, complete with a fully customisable human-machine interface (HMI) that recognises touch gestures, an extensive suite of optional machining functions, and a powerful 3D simulator for part program verification and visualisation of machining processes. A choice of three CNC kernels, Flexium+ 6, Flexium+ 8 and Flexium+ 68, enables machine designers to deploy technically and economically optimised solutions for different machine tool applications. Flexium+ 6 and Flexium+ 8 will control up to four interpolated axes and a spindle where it is dedicated to machines which need a higher degree of flexibility. Flexium+ 68 supports larger and more complex machine control applications and provides up to eight CNC channels, each accommodating up to nine interpolated axes and as many as 32 spindles. In total, a single Flexium+ 68 CNC kernel can accommodate 32 connected devices, any of which can have interpolated axes or spindles. This universal control approach simplifies spindle/C-axis commutation and provides a foundation for multi-spindle applications such as transfer machines. An enhanced part program structure enables machine designers to take advantage of the CNC hardware's versatility. Each channel runs its own part program asynchronously and operates autonomously, much as if it had a dedicated CNC kernel, or it can be synchronised to other channels. Control of one or more axes or spindles can be passed from one channel to another on the fly to maximise use of available hardware resources. In each channel, four spindles can be operated in a master/auxiliary arrangement, with real-time control of their speed, direction and indexing to simplify implementation of complex machining operations. The master handles advanced CNC functions – such as maintaining constant surface speed while the workpiece changes diameter during processing, or continuously tracking angular position during thread cutting – with the three auxiliary spindles handling associated higher speed machining. Multiple Flexium+ 68 CNC kernels can be interconnected via real-time Ethernet, which enables the realisation of control systems with more than 200 interpolating axes. The ability to drive multiple CNC kernels and control this number of axes with a single automation PLC is a feature of NUM's CNC architecture. To help OEMs implement rigorous machine safety schemes, Flexium+ introduces a comprehensive system-wide safety architecture known as NUMSafe. All critical system operations are overseen by a safety PLC module. In conjunction with NUM safe I/O modules and servodrives – which incorporate safe motion monitoring circuitry – the safety PLC enables machine designers to implement high integrity safety functions with very few additional components. NUMSafe is inherently scaleable, requires minimal extra wiring and uses a Fail Safe over EtherCAT (FSoE) protocol to ensure integrity of all safety-related data. The architecture complies with the EN ISO 13849-1 machinery safety standard up to PLe, and with the EN 61800-5-2 functional safety standard for variable speed drives, up to SIL 3. Available in single and dual axis versions, digital servodrives – NUMDrive X – offer a choice of two performance levels, with outputs from a few amps to 200 Arms. A high degree of functional integration keeps the drives very small. To further simplify design-in, the drives' safe motion monitoring board is available in a basic version with Safe Torque Off functionality, and in an extended version which adds Safe Operating Stop, Safe Stop 1, Safe Stop 2, SafelyLimited Speed and Safely-Limited Position functions. NUMDrive X servodrives are significantly faster than NUM's earlier-generation NUMDrive C products. Advanced DSP control increases CNC-drive servobus speed by 100%. Together with improvements to the drives' bandwidth – by as much as 25% – and enhanced acceleration algorithms, machine designers do not need to sacrifice resolution during extended axis travel, or trade traverse rate against positioning accuracy. A numerical processor in the CNC kernel further improves CNC resolution and accuracy with the software enhanced to utilise high precision format, allowing for finer interpolation and speed control. To speed development of part programs, Flexium+ provides a unified suite of software tools with a consistent look and feel. All CNC, servodrive, I/O, automation PLC and safety PLC functions are set up and programmed using a single tool. The automation PLC offers a choice of IEC 61131-3 compliant graphical and textual programming languages, while the safety PLC is programmed using simple function blocks and Boolean operators. Flexium+ also offers a fully customisable HMI to facilitate improved ergonomics. Dual touch gestures such as 'wipe', 'expand' and 'rotate' can be incorporated to capitalise on NUM's touch-sensitive operator panel, while virtual keys can replace physical keys to further simplify machine operation and reduce build costs. Manually-written or CAM-generated part programs can be verified and optimised using NUM's Flexium 3D graphical simulation software on an offline PC. Alternatively, the software runs on the operator panel, taking advantage of its multi-core processor PC and 19-inch screen, and interacting with the machine's CNC unit, to simulate part programs either before they are run, or simultaneously with part processing. Users can visualise the path of the tool centre point, simulate material removal and check for collisions. As standard, the software can simulate a wide variety of machining functions including grooving, thread cutting and tapping on 3- to 5-axis turning machines, milling and drilling on 3-axis machines, and contour cutting. A diverse range of application support software covers machining functions such as grinding, turning, milling and cutting, as well as gear hobbing, shaping and finishing. The latest additions include functions for water jet and plasma cutting machines, using 'tilted nozzle management' algorithms to prevent under or over-cut edges by automatically compensating for the conical shape of the beam. The Flexium+ CNC platform is backed by NUM's extensive portfolio of motors. The company is also introducing two ranges of brushless axis motors designed for use with the NUMDrive X servodrives. These drives incorporate an innovative digital encoder interface which dispenses with the need for a separate cable by carrying encoder power and data on a two-wire link embedded into the motor cable. The new SHX and SPX brushless axis motors have a single connector and cable, simplifying installation and reducing wiring costs.