Posted to News on 2nd Oct 2006, 17:32
Motion and machine control for packaging and processing machines
Within the packaging and processing industry, many manufacturers use motion controls, PLCs, HMIs, and vision systems from different vendors; Aerotech specialises in providing such integrated products and systems from a single source with an extensive range of feature-rich motion and machine controls, high-performance servo and stepper drives and brushless linear and rotary servomotors with the advantage of lower system and integration costs, faster time to market and lower life-cycle costs.
Aerotech's A3200 Automation Platform is a software-only, 32-axis distributed motion control system that runs on standard Windows-based PCs and combines tightly synchronised motion with a selection of 'soft' machine control modules for HMI, vision and PLC. Using the non-proprietary IEEE-1394 Firewire protocol, the controller provides a fully deterministic, high-speed, distributed control architecture in combination with Aerotech's Ndrive servo amplifiers which independently process position and velocity motion updates at 20kHz servo loop closure rates, with power ratings up to 100A peak current. Multi-axis packaging machine operations such as fast registration or 'virtual line-shaft' based synchronisation are easily undertaken with all motion commands accessed in C, C++, Visual Basic or in AeroBASIC - a rapid prototyping development language based on RS-274 G-code. Alternatively, the optional Ncontrol SDK software development kit may be used to program the unit with Windows-based ActiveX components, C++, VB and .NET class libraries that help to reduce programming time and effort.
Machine control modules are available for HMI (Nview) and PLC (Nlogic) with the industry-standard IEC61131 language. A vision control module (Nvision VCM) supporting standard and non-standard cameras greatly simplifies quality control or part identification requirements. As well as the integrated 10 base T Ethernet port on Aerotech's Ndrives, a DeviceNet-compatible module is available for interfacing third-party analogue and digital I/O or other machine control components. The A3200 allows simplified system wiring with its Firewire-based distributed network and provides a very high speed deterministic architecture that is future-proof and able to deal with the most complex motion and machine control requirements.
A wide range of Ndrives is available to suit precision servo applications from 10A peak current at 80V DC to 100A peak at 320V DC in a choice of standalone and rack-mounted configurations. Digital PWM-based drives may also be configured for use with stepper motors and a range of linear power stage amplifiers is available for low-noise, low-distortion requirements sometimes necessary for sensitive medical and electronic packaging applications.
Upgrade legacy systems
Aerotech can also upgrade existing 'legacy' systems with its Nservo and Nstep multi-axis interfacing system, allowing A3200 performance to be achieved on original servo- and stepper-based drive systems, thereby extending the useful life with overall capital equipment cost savings.
An alternative motion system approach is available with Aerotech's multitasking Soloist intelligent drive - a single axis digital servo drive and motion controller with 10/100 Base T Ethernet and USB connectivity. Suitable for single-axis motion and machine control applications or as a multi-axis networked system for up to 1024 units, the Soloist combines advanced (.NET) software architecture with an integral power supply, a digital drive amplifier with up to 30A peak rating and advanced motion and machine controls.
The Soloist is aimed at demanding packaging machinery applications where high-precision operations such as flying shear, electronic cam and electronic gearbox may be performed individually with networked synchronisation of the total machine process.
Soloist's modular construction allows for optional I/O expansion boards and other scaleable add-on features such as a second encoder input for advanced position following. There are also Modbus-over-Ethernet master/slave capabilities with status and commands performed over Ethernet or through USB. An RS232 link is also provided for interfacing HMIs and other peripheral devices. A standalone version for use with an external power supply is also available, reducing system costs for multi-axis packaging and processing machine applications.
All Aerotech motion controllers include extensive program development and set-up facilities such as autotuning and extensive diagnostic functions. Motion and machine control programming is also possible with LabVIEW virtual instruments. Processing and packaging operations available include simple load/unload, product spacing, marking and printing, feed-to-length, labelling, high-speed registration, electronic cams and multi-axis electronic gearbox, web tensioning, force and torque control.
Advanced control functions
Other advanced control functions include real-time target modification where a move in progress may be modified for speed and/or position to accommodate interaction of external events through I/O or software. For example, a vision system may be integrated and used to correct inaccuracies in part placement during the move. Programmed moves may be adjusted in-situ to take care of web stretching or slip, guaranteeing consistent quality with no time loss for adjustment or need for a secondary corrective move. The PSO (Position Synchronised Output) command was developed for laser firing applications but may be applied to labelling and print processing applications where a very high accuracy output signal can be 'fired' at precise intervals along a single axis or a combined multi-axis trajectory. Motion and machine synchronisation of product processes with external conveyor drives and analogue and digital sensor systems feedback are all possible.
Aerotech also supplies complete motion subsystems with a range of linear and rotary positioning tables for medium- to very-high-precision applications, although many packaging and processing machine requirements are fulfilled with specialist customer-supplied mechanics, interfaced with Aerotech's motors. These include 'U' channel and flat brushless and slotless linear servomotors which are ideal for many industrial applications. The non-contact, direct drive design has zero backlash and inherently smooth and precise motion. Aerotech also offers a wide range of rotary servo motors that can be tailored to application requirements for both cost and performance.
