Latest automation technology helps companies retain competitive edge

In this second article from Parker Hannifin, Nigel Steel, from the electromechanical and drives division looks at the latest automation technology and at how the newest modular systems can help users reduce operating costs and improve productivity.

Robotics systems have been widely used for a range of duties in the automotive and electronics manufacturing sectors for many years, where production volumes enable the relatively high cost of automation to be more easily absorbed. Until recently, however, the uptake of robotics equipment in other sectors of industry, has been somewhat restricted due to relatively high capital costs and system complexity. This is especially true in applications such as pallet handling, case erection and component pick-and-place, for products ranging from building materials and DIY goods to food and medical cartons.

With current market pressures placing an increasing need for companies to be extremely flexible, able to respond quickly to short term changes in market conditions or urgent customer orders, a growing number are realising the benefits that can be offered from the use of a wide variety of automation equipment. Perhaps as importantly, the use of the latest generation of automation technology is enabling the costs of production and materials handling to be driven down, helping end users to protect operating margins and stay ahead in today’s increasingly challenging global marketplace.

Despite this fact, there are still some sectors of industry, particularly where volumes are smaller or where short run product variants are being manufactured or handled, that are being slower to automate many of their production processes, but which could nevertheless realise real technical and commercial benefits.

The main issues that have stalled the wider uptake of automated palletising and gantry systems in such applications have generally been the high capital costs and the length of time that has typically been required for system design, build, testing and installation. It is not unusual for this process to take many months as well as often involving repeated on-site adjustments before a system runs effectively. Moreover, many of these custom built systems are suitable for one purpose only and can be difficult and expensive to reconfigure quickly. Collectively, these issues make it particularly difficult for companies to meet rapidly changing business needs.

ParkerIn response to these problems and to make automation a far more viable option in a much wider range of applications, a number of leading manufacturers have developed innovative new systems that are supplied either pre-assembled or as kits, enabling them to be constructed and commissioned quickly and easily on-site. These systems are easy to configure, install and test, and can usually be reconfigured quickly and simply by maintenance or engineering staff, making them particularly suitable for use in small to medium volume applications where product changeover frequently requires adjustments to handling mechanisms. Additionally, further technological advances now mean that such systems are available at relatively low capital cost and are typically inexpensive to operate and maintain; indeed, it is not unusual for such systems to be making a return on investment within weeks of initial installation.
An integral element and key to the success of this new generation of automated gantry and palletising systems is the use of the latest modular drive and automation parts, in particular, high performance linear motion systems, digital servo drives and easy to program controllers. Generally, these devices are supplied either as basic assemblies or sub-systems, for instance a simple X-Y line gantry unit with linear actuator, gearbox and motor, ready to fit into an existing support structure. They could also require an integrated system capable of complex multi-axis motion, delivered complete with all cabling, switches and sensors for a new build installation.
Line- and space-gantries, along with palletising systems, generally rely on linear actuators to control the movement and positioning of work-pieces such as tools, gripper’s or suction pads, and the products or packs being handled. In essence, there are a variety of basic types of linear actuators suitable for use in automation systems. Each type features a slide mechanism that is driven either indirectly from a separate motor via a belt or screw mechanism and appropriate gearing or directly by means of a linear motor that is integrated into the body of the actuator.

Depending on the application, each of these drive methods offers a number of advantages. For example, belt drives are generally simple, low cost devices that can operate at high speeds with rapid acceleration, but are limited in terms of accuracy and overall performance. Screw drives, on the other hand, offer excellent rigidity with a reasonable degree of precision and resolution. By comparison, systems that incorporate linear motors offer exceptional levels of precision, deliver very high speeds and acceleration, require virtually no maintenance and provide a long operating life.

Some of the latest, most sophisticated systems incorporate high-performance actuators that use timing belts or rack-and-pinion drive units to provide high speeds of 5m/sec, precision and repeatability to within ±0.05mm, with the ability to handle heavy loads of up to 1,600kg. Additionally, these devices can offer extended travel for particularly large gantry systems, with a standard actuator running up to 6m and longer runs being possible by mating two or more units together.

Alternatively, linear motors provide an ideal solution for systems where there is a specific need for extremely rapid acceleration with precise positional accuracy and repeatability. This is because linear motors are capable of operating at speeds of up to 10m/sec with rates of acceleration of 50m/s², and repeatability of just ±0.1μ. By comparison with many other traditional devices, linear motors do not suffer from backlash and can be supplied with integrated encoders to enable the position of the items being handled to be accurately determined.

Another key element of the latest gantry and palletising systems is a reliable control system. The use of standard or modular devices, such as Parker’s Compax3 family of digital servo drives and controllers, are essential for reducing the cost, complexity and lead times of the latest automation systems. In particular, the ability to interface these control devices directly with standard PCs and Windows operating systems, as well as the use of easy to learn and use programming techniques, in turn, allows gantry and palletising systems to be commissioned and set-up rapidly and simply on-site. Furthermore, production and maintenance engineers can subsequently reconfigure such systems and operating programs to suit any future needs, enabling companies to remain flexible and adaptable to rapidly changing conditions.
Collectively, the recent technological developments in automation systems have enabled leading suppliers to introduce innovative gantry and palletising systems that are faster, smaller, more cost effective and, in general, perform far better than ever before.
This, along with the introduction of packaged or integrated solutions, is enabling both OEMs and end users alike to benefit from quicker specification, installation and set-up, reduced maintenance requirements, longer product life and enhanced system performance. Perhaps most importantly, the new generation of handling systems offer a number of important benefits that enable companies to retain a competitive edge, which is vital at a time when industry is coming under increasing pressure to boost productivity and meet ever shorter lead times, while simultaneously cutting operating costs.

Parker Hannifin is the world’s leading diversified manufacturer of motion and control technologies and systems, providing precision-engineered solutions for a wide variety of mobile, industrial and aerospace markets.

Micromech is the UK distributor and systems integrator for Parker Hannifin electromechanical products. For more information contact Alan Spinks on 01376 333333 or alan@micromech.co.uk

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A new parallel linear shaft motor option

The Linear Shaft Motor is very unique linear motor; its design allows engineers the ability to drive two or more motors in parallel using only one encoder and one driver. 

Micromech is the sole agent for Nippon Pulse and boasts several success stories with both two and four motor parallel drive systems. All these options require only one encoder and one servo driver.

There is a range of shaft diameters from 4 to 100mm with stroke lengths of 20mm all the way up to 4.6M. They have achievable peak force of 2340N and maximum continuous force of 585N. An important feature of these motors is the large air gap between shaft and forcer which means there is much less costly machining of the system.

Cartesian RobotParallel drive systems are most commonly thought of as being used in Cartesian/Gantry robots. Nippon Pulse defines the parallel drive system as any application that has two or more linear motors in parallel. While this definitely covers the Cartesian/Gantry style robots, it also includes other major areas of motion control which include:

High-precision and ultra-high-precision single axis robots                                            
(These have a resolution and position accuracy in the sub nanometer to high-picometer range)

  • Optics
  • Microscopes
  • parallel linear shaft Semiconductor
  • Machine Tool 

Actuators where very high force is needed

  • Material testing equipment
  • Punches

Cartesian/Gantry robots.

  • Pick and place work
  • Glass cutters
  • Application of sealant
  • Assembly operations
  • parallel linear shaft motorHandling machine tools
  • Laser engravers
  • Arc welding

While this is not an all inclusive list it clearly shows applications in both the micron and submicron world.

The major issue with all parallel drive systems (e.g., gantries) is orthogonal alignment (the ability to keep the parallel axis square). In mechanical driven systems (screw driven, rack and pinion, belt, and chain drive for example) the main problem that arises is binding of the system due to misalignment or stacked up tolerances of the mechanical system. In direct drive systems there is an added issue of sine error that is introduced due to installation errors and variances in the linear motors themselves.

To overcome these issues, the common practice is to drive and control each side of the parallel system and electronically synchronise them. The cost of such a system is higher since it requires twice the electronics (drivers and feedback, etc.) when compared to a single axis system. This type of tracking control system can also add synchronisation and tracking errors, which adversely affects the performance of the system.

The advantages offered by the Linear Shaft Motor are due to a highly responsive motor; this makes connecting them into a parallel system not only possible but also easy.

As with all parallel drive systems, the Linear Shaft Motors must be physically coupled with a mechanism, which when applied, allows the axis to realize only one-degree-of-freedom of movement. Since the dynamic motion generated by any two identical Linear Shaft Motors, when given the same control signal is the same, the asynchronous motion of the above described parallel system is inevitable. This in effect makes the parallel Linear Shaft Motors act as a single unit. This makes it possible to operate the system with a single encoder and single servo driver.

The Linear Shaft Motor is a non-contact system, when installed properly, it is impossible for it itself to introduce any mechanical binding into the system.

While what is stated above is true of any non-contact linear motor, what makes Linear Shaft Motors different from other non-contact linear motor? The issues that could cause force differences in any non-contact linear motor, thus causing system binding, performance loss, or synchronization and tracking errors are as follows:
An inherent advantage of the Linear Shaft Motor technology over other non-contact linear motor is that the design of the Linear Shaft Motor with the magnet in the center makes the air gap non-critical. The coil completely surrounds the magnet, so force is the net effect of the magnetic field. Any force variation that would have been caused due to air gap differences, such as alignment, or machining differences is all but done away with. This makes alignment and installation of the device very simple to do.

This is true of all cylindrical non-contact linear motors; however what makes the Linear Shaft Motor any different to them is one more major issue that could cause force differences in any non-contact linear motor – sine error.

Linear motors are defined as synchronous motors where current is applied to the coil to form an electromagnet. The coil then synchronises itself to the magnetic field generated by the permanent magnets in the magnet track. Force in a linear motor is generated due to the relative strength of these magnetic fields and the angle of their intentional misalignment.

parallel linear shaft In a parallel drive system when the magnetic fields of all the coils are perfectly aligned and the magnetic fields in all the magnetic tracks are perfectly aligned, they in effect become a single motor without any differences of force generation. However any misalignment of the coils or magnetic tracks will cause the angle of misalignment of the magnetic fields in the motors to be different from each other, thus producing different forces in each motor. This force difference can in turn cause binding in the system. So sine error is the force differences produced, due to misalignment of the coils or magnetic tracks.

Sine error can be calculated by the following formula:

Fdif – Force difference between the two coils
Fgen – Force generated
Ddif – Length of misalignment
MPn-n – North to North Magnetic pitch

Most linear motors on the market are designed with a north to north magnetic pitch in the range of 25 to 60 mm long under the guise of trying to reduce IR losses, and the electrical time constant. For example a misalignment of just 1mm in a linear motor with a 30mm N-N pitch will cause a loss of about 21% of its power. The Linear Shaft Motor however uses a much longer north to north magnetic pitch to reduce the effect of sine error due to accidental misalignment. Therefore the same misalignment of 1mm in a Linear Shaft Motor with a 90mm N-N pitch will result in only a 7% loss of power.
Parallel Drive Systems Summary
The Linear Shaft Motor was designed for high-precision and ultra-high-precision single axis robots. In these types of applications, truly accurate positioning is only possible when the feedback is directly in the centre of mass of the work point. Applications require the force generation from the motor to be right in the centre of mass of the work point however it is impossible to have the motor and feedback in the exact same location. Putting an encoder in the centre of mass and using parallel Linear Shaft Motors equally spaced off the centre of mass in effect achieves the desired feedback and force generation in the centre of mass. This is impossible for other types of parallel drive systems which require two sets of encoders and servo drives to provide this parallel drive functionality.
Designed for ultra high precision markets this capability is a huge advantage for gantry system builders as in the past systems may have used two different motors driving separate ball screws using two different controllers. These would be electronically connected together, or even two linear motors with two encoders electronically connected together with two drives. Now it can be accomplished with two shaft motors, one encoder and one amplifier, as long as the stiffness in the system itself is sufficiently high.
This is also is an advantage for applications where extremely high amounts of force are needed. It is possible to connect any number of Linear Shaft Motors, thus allowing their forces to be added together.

Examples of Parallel Linear Shaft Motor System

Examples of Parallel Linear Shaft Motor System

New from Micromech is the NANO Z ™ novel air bearing lift stage

Just launched with a patent pending is the Alio NANO Z™ a novel air bearing lift stage with TRUE NANO POSITIONING™ and to help engineers and scientist further, it has been designed with a large open centre.

It uses linear servomotors and variable counterbalance to exceed precision application needs such as wafer inspection, where heavy ceramic wafer plates need electrical and vacuum lines fed though the positioning stage.

Nano ZOther applications such as TRUE NANO™ metrology, optical inspection and laser machining are performed at accuracy levels less than 100nm without the concern of ballscrew thermal growth, wedge lifts tip and tilt, non-repeatability and inaccuracies of other legacy designs.

The NANO Z™ clever design almost eliminates pitch, yaw and roll over the 24mm travel range with better than 90nm of repeatability in the standard unit. Optional extreme precision Nano Z™ will deliver an amazing 10nm of repeatability with better than 50nm of accuracy.

The NANO Z™ footprint is optimised for compact size due to the novel air-bearing and linear motor design thus it can easily sit on top or inverted on an XY motion system. For metrology or other processes this means no increase in the motion system’s overall vertical footprint or the need for special mounting compared to other designs where the Z axis lifts with motors and screw that need four times the vertical distance.

When an application needs TRUE NANO POSITIONING™ contact Micromech to be assured proposals are not based on resolution but of TRUE NANO™ repeatability and accuracy, measured in six degree of freedom with US National institute of standards and technology traceable metrology data.

If you would like more details about these exciting precision stages then contact Stirling Morley on 01376 333333 or email on stirling@micromech.co.uk

Food for thought – Sponge cake and waffle machine

More success stories from the most diverse applications which partners Micromech Systems and Parker has been supporting for food processing equipment and packaging machinery manufacturers.

Sponge cake and waffle machineSponge cake and waffle machine

A manufacturer of machinery for the production of waffles faced customers complaining about too many defective products. The cause of these many rejects was due to complicated cutting processes of the dry and brittle waffle products resulting in product breakage.

In close co-operation with engineers they developed a mechatronic solution using a highly dynamic electro thrust cylinder pushing the product through a fixed cutting grid. Thanks to the special motion profile of the cylinder the breakage rate could be considerably reduced. The solution was made possible via decentralised servo drives, which can be seamlessly integrated into the customer’s proven control Sponge cake and waffle machinearchitecture using Profibus. The next problem was to tackle the inevitable waffle dust in order to prevent it from entering the body of the electro thrust cylinder. Parker developed an application specific sealing system with air purge at the thrust rod outlet for this customer.

This simple but effective modification resulted in shorter cycle times, a dramatically reduced number of rejects and an increased total plant efficiency due to more than 43,000 precisely controlled double strokes per day.

The much shorter cycle times and considerably reduced product wastage meant the manufacturers customers were very happy, the successful upgrade of the new machine expanded their market and as a result all are delighted with the outcome.

Micromech is Parker’s motion partner and can offer a bespoke solution to meet all of your motion control needs, for more information contact Alan Spinks on 01376 333333 or alan@micromech.co.uk

‘Micromech Systems and Parker are forces in motion’

Parker Bayside

Parker Bayside

It is common knowledge that Parker Hannifin took over Bayside Motion and set about introducing the Stealth ranges of high quality, high performance gearboxes. We recently discovered a proportion of customers are concerned about the prospect of replacement and repairs of the original Bayside gearboxes in the event this is required.

MIcromech is pleased to advise its customers that the Stealth ranges are ‘drop in’ replacements for the Bayside gearboxes boasting a superior quality standard. Contact Alan Spinks today for information on how to keep your equipment running.

Micromech also carries out your repairs and servicing of Bayside boxes so call 01376 333333 if you wish to arrange a return.

Stealth

The Micromech team in training for the 2014 winter olympics

Simon, Peter, Dave, Phil and Stirling Phil
Simon and Richard Catherine
Peter, Phil, Stirling and Simon

‘Simon Burrows, Peter Whitmell, Dave Whitmell, Phil Farnworth, Stirling Morley, Richard Matthews and Catherine Swiba – they are a force in motion’

Meet the team – Ros Greene

Hello to you all, my name is Rosalia Greene but most people call me Ros. I am a Sales Co-ordinator and the new addition to Micromech’s very dynamic sales team!

I was born in Surrey and lived in Walton-On-Thames for 25 years – yes I know, you are probably wondering why I moved away from ‘leafy Surrey’ to Braintree in Essex? Well, the simple answer to this is that we, my partner Dan of nearly 7 years together and I, decided it was time for us to tie the knot. So we married in September 2009 and then it was his work commitments that brought me here!

Ros GreeneAfter leaving St Mary’s College, University of Surrey, where I studied a Ba Hons in Media Arts and Drama, I decided not to pursue my earlier ambitions to launch a career in the world of performing arts or television production as initially planned. Instead I opted to choose a career in Sales…….I guess again you are puzzled, where is the connection? I know, curious move huh! Well the answer I suppose to the decision to follow this path was down to my personality. As I am a confidant and a go-getting individual who enjoys interacting and socialising with others – sales was for me.
I’ve had held a number of positions in sales including Customer Sales Assistant and Account Manager in the building maintenance and facilities industry. My primary duties in this market were to retain and develop existing customer base as well as introduce and develop new business opportunities. Like many other professions, working in sales has had its ups and downs, however I have gained a great deal of customer service experience and skills along the way together with meeting many great people.

I started Micromech, in April 2010 on a temp-basis and then was offered a permanent position. My job entails putting together quotes and orders, as well as taking enquiries and doing my very best to help customers such as you. I enjoy the work, as it is a real mix of products and technologies, which makes it interesting, keeps me busy and really on my toes!

Now a little bit about my self outside of work. Well I enjoy going out with my husband at the weekends for meals and of course not forgetting shopping! Many would say that I have too many handbags and shoes! Trouble is I can’t really deny this, as it is very true. I come from a big family and being Sicilian (that’s right my family are from Sicily, well know for its Mafia connections!) which means we have many family gatherings and occasions, so of course its essential I dress well.
I am very close to my family, there is my mum and dad Lia and Vincenzo (who are great parents) and I am one of four children, two sisters called Giuseppina and Laura and a brother called Lucio.

I just love going on holidays and desperate to see more of the world which I will do as time goes on. So far I would say the best holiday I have had to date would be our fabulous honeymoon as it was pure adventure, romance and paradise all in one. We spent an amazing week in Sri Lanka and then another week on a small idyllic and ‘out of this world’ island in the Maldives.

Anyway that’s enough about me.

Back to business, I really look forward to hearing from you with any enquiries that you may have to help me finish an exciting and enjoyable year.


Previous meet the teams –

Jon Harding, Clarissa Snowsell, Sarah King, Simon Burrows, Richard Matthews, Joe Marshall, Alisia Cherry, Phil Farnworth, Mick Stone, Peter Searle, Cara Woods, Mark Hall, Alan Spinks, Sarah-Louise Parrish, Dave Whitmell, Gina Warwick, Trevor De Wilde, Stirling Morley,