Doing it with robots

Advances in robotics technology – such as machine vision, control systems and greater flexibility – means that robots are becoming more effective at improving a diverse range of manufacturing processes.

Earlier this month, Warwick University hosted the first- ever UK Robot Football Championships where, ahead of thissummer’s European Robot Football Championships in Munich, rival robots equipped with cutting edge technology were pitted against each other.

While an entertaining application of a technology, this competition clearly demonstrates the progress made in the field of intelligent systems. Robotic ability in real time applications is a fundamental aspect of growth.

Advances in robotics technology – such as machine vision, control systems and greater flexibility – means that robots are becoming more effective at improving a diverse range of manufacturing processes. They are also getting cheaper.

Small to medium-sized enterprises, and sectors that are not traditionally big robotics customers are set to benefit, and without the need for radical change to their processes.

For example, it is possible for the food or plastics industries to integrate robots into downstream production operations. Instead of employing a robot to just pick and place, the intelligent system could further modify and add value to the product at the same time. Adding capability to the less critical parts of the production process, such as assembly and packaging, makes robots more affordable and also sharpens the competitive edge.

Figures from the International Federation of Robotics in 2003 show that worldwide orders for industrial robots increased by 26 per cent on 2002, the highest ever recorded. According to BARA (the British Automation and Robot Association) approximately 850 robots were installed in the UK in 2003, up from 700 in 2002. While the automotive industry has traditionally represented the largest chunk of the market, cheaper, more powerful, flexible and more controllable robots from companies such as ABB, Comau, SIG and Staubli have enabled manufacturers who are not normally associated with robotics and automation, to take advantage of what the technology offers.

There is an argument, increasingly accepted, that investment in robotics, rather than traditional automation systems must be adhered to for manufacturers to remain efficient, profitable and competitive. The loss of manufacturing contracts to overseas companies operating in low-wage economies is an area of concern for many.

According to chairman of BARA, Dr Ken Young, the plastics and the food industries are two such areas. While both represent a small share of the market for new robots (one per cent and five per cent respectively) they are now, thanks to the improvement and lower cost of the technology, increasingly investing in robotics and automation to improve productivity.

‘The plastics industry in this country is realising it has got to do something more than can be done in China and India. And the only thing they can do is integrate a lot of processes downstream of the moulding operation,’ said Young.

‘As soon as they have moulded something they take it out with a robot and clean it off, spray it maybe and assemble various components on to it. In this way they are adding a lot more value to it rather than just delivering a basic plastic moulding to the customer.’

More manufacturers see this type of integration as the wayforward. C&C Marshall is one such company that is integrating a number of activities associated with moulding. In a bid to reduce man hours on the shop floor and increase production it has installed two TM Robotics SR-554 HSP SCARA robots at one of its plastic moulding plants. This has allowed a number of manual processes to be automated. The TM robots place components into moulds or boxes, which are then placed on to a packing carousel.

The robots can adapt to a range of product variations, and can produce 10,000 units a day at its most simple setting. Before automation the components were manually inserted into boxes which proved not only inefficient, but a consistent cause of repetitive strain injury.

The entire system now needs only three people to operate, where previously eight were required. The TM Robotics machines were selected over five-axis systems because they offer greater speed and improved accuracy.

In another development, ABB & SIG Pack both recently provided Delta robots for the food industry. One customer, Wagner Frozen Foods of Germany, has introduced a robotic packaging line at its facility in Braunshausen, which produces mini pizzas for continental Europe.

Efficiency was considered to be suffering, where at a maximum output, 900 pizzas were produced every minute. The new system comprises three SIG Delta robots, each capable of placing more than 100 triple pizza packs a minute into the ready-formed boxes from a carton former.

The packages are detected using a vision system with image processing that enables each robot to locate a package accurately and place it in a

carton. This improvement in packaging efficiency has seen Wagner increase its production to 1.2 million packs a day. Total investment of the SIG Delta units including maintenance was e1.2m (£803,223). Significant improvements in vision systems, control technology and intelligence have also played a key role in the increasing flexibility and ease of use.

‘Machine vision has come a long way over the last few years,’ said Young. ‘Machine vision camera technology and software is making robots more intelligent and enabling them to carry out a greater number of tasks.

Instead of seeing a camera as a one dimensional object, capturing an image, it has become a far more intelligent and flexible tool that has simplified robotics and has become far more adaptable.’

The improvement in software as well as hardware is key to the wider uptake of robotics.

According to Young three-axis robots were used to simply load and unload. Now six-axis robots are loading and unloading and proceeding to do downstream operations.

‘Once you’ve picked the part up, it makes sense to do as much as possible to it before you put it down again,’ he said.

Robots have existed in a manufacturing context for many years, but have become much cheaper, easier to use and far more accurate – a four-axis SCARA robot, for instance, has halved in price to £12,000 over the past five years.

Two of the latest technical innovations from Industrial Vision of Oxfordshire demonstrate the progress being made in machine vision and how simple it is becoming to operate.

Firewire digital cameras give digital transmission without the need for any separate technology to digitise the image, while the ‘contour matching wizard’ means a robot positioning application can be set up in a matter of minutes. Compared to traditional software and analogue cameras this has the potential to save days, even weeks.

‘With the increased ease of use of vision systems in conjunction with robots I think the growth in this area will continue at a rapid rate for those vision system vendors with easy-to-use, graphical display vision solutions,’ said Industrial Vision’s Earl Yardley.

As automation has become more sophisticated, robots have kept pace. And as they become more attainable, the compromise between accuracy and repeatability is of major importance.

In February, surgeons from Guys and St Thomas’ Hospital hosted the first ever symposium on using robots for urological operations. This followed trials conducted last year to demonstrate thebenefits a robot would bring to surgery, eliminating both hand tremor and an improved level of accuracy.

In the trial, the number of times the human hand inserted the needle into the correct spot on the first attempt was 79 per cent compared to 88 per cent for the robot. This is essential, for example, in the early stages of a kidney stone operation, as the needle has to be inserted into a very precise area of the kidney.

While robots currently assist in a complementary capacity in orthopaedic and orthroscopic surgery, Dr. Patrick Finlay of medical robotics company Armstrong, admitted that the ultimate goal is to develop a robot able to operate on a beating heart.

While this is some way off, brain surgery is the immediate goal for robotic-assisted surgery, with improving vision systems enabling surgeons to be far more accurate. This is crucial when dealing with tumours for example. In engineering terms the success of this image-guided surgery will come from the registration of CT scans which will come about with improved machine vision software.

Whether the UK will push investment and continue to invest in robotics remains to be seen. Currently too many companies are not concerned with improving their process, but happy to get by with cheap labour to carry out the more innocuous tasks that really do not need any human involvement.

Dr. Young points to the recession and lack of confidence in UK manufacturing for this reluctance to invest.

‘Sweden and Italy have moved forward and overcome this problem and we haven’t. The current mentality is to employ cheap labour for jobs which can be handled effectively by robots,’ he said.

As C&C Marshall has shown, sometimes an improved process is the answer, rather than simply investing in extra machinery to speed up productivity.

A reduction in price and improvement in user-friendliness might conceivably have an impact on another burgeoning section – modular robotics. This is the use of a number of simple robots to perform complex tasks. As Young points out, a lot of people have been looking at it for a while, but when you make a machine modular, there’s cost involved.

A six-axis robot is generally now almost as competitively priced as three-modular axis. Some feel that today it is better to invest in a six-axis robot and use that for all the applications.

Modular robotics, however, allows firms to invest in one standard robot to carry out varying tasks. The BMW plant at Cowley in Oxford, for instance, employs 273 robots of which 85 per cent are of the same generation of Kuka robots. This means standardised parts and a familiarity from a customer point of view.

While traditionally automation is the monopoly of largemanufacturing sectors, smaller industries are becoming increasingly aware of its benefits. They know how it could be applied to some of their processes and that it won’t break the bank to do so.

Improved vision software, greater accuracy and flexibility means robots are far more accessible than ever before – whether companies have the confidence or foresight to invest in the long term is another matter.