robotics and automation in the food industry || robotics and automation for packaging in the...

© Woodhead Publishing Limited, 2013

17

Robotics and automation for packaging in the confectionery industry J. S. Dai , King’s College London, UK

DOI: 10.1533/9780857095763.2.401

Abstract : The confectionery industry is characterised by short runs and small batch production, thus confectionery packaging is frequently accomplished manually, resulting in wastage, injuries and hygiene issues. Automation of packaging in the confectionery industry would reduce these problems; and the frequent change-overs due to the large variety of products under manufacture necessitate an extremely versatile automated packaging system. This chapter describes market trends in the confectionery industry and the industry’s packaging needs and reviews reconfigurable mechanisms and the potential for flexible packaging automation in the confectionery industry. A case study of a reconfigurable demonstration system is outlined.

Key words : packaging, automation, reconfigurable mechanism, robotics, confectionery.

17.1 Introduction The confectionery market is a highly seasonal and competitive market, with cus-tomers demanding unique products supplied in innovative packaging with a high on-shelf impact. Significant characteristics of the industry, especially in the pro-duction of seasonal products and other gifting products, are the range of packag-ing formats in existence, the speed with which they are changed, and the small production runs required to produce different products for different customers. Sales in the confectionery market are also increasingly driven by promotional activities including BOGOF (Buy One Get One Free) and other price promotions. The costs of these promotional activities are borne by the manufacturers, whose margins are being squeezed year on year. To be competitive, manufacturers are

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402 Robotics and automation in the food industry

being forced into using lean production, increasing productivity, reducing waste, utilising labour efficiently, and reducing machinery downtime. While some pick-and-place operations are automated by using robots such as delta robots, end-of-line packaging is still often achieved using manual work, due to the variety of products manufactured (Dai, 1996a , 2005 ). This is a more expensive process, though, which adds to the cost of the final product, particularly when an expen-sive seasonal labour supply is required. The above suggests that what is required is automatic reconfigurable confectionery handling and packaging in appropriate forms. This would enable manufacturers to exploit the seasonal confectionery market, allow leaner production with reduced rejects and downtime, and increase market opportunities. This chapter considers what is required for such a reconfig-urable system and describes a demonstrator system that was created to illustrate what can be achieved.

17.2 The confectionery market and its business requirements The confectionery market is one of the major markets in the food sector and pres-ents a major market for food packaging. This section describes the confectionery market in more detail, in particular the specific requirements of this market.

17.2.1 Market size In the confectionery market, France consumed 597 000 tonnes in 2000 and over 667 000 tonnes in 2006; Germany consumed 792 000 tonnes in 2000 and 833 000 tonnes in 2006. The United Kingdom has its place as one of the world’s major consumers of confectionery. Overall consumption of packaged confectionery in the United Kingdom increased by 6.5% to 992 000 tonnes in 2006 (see Fig. 17.1 ), with unit sales of food by carton approximately 2.4 billion units in 2001, and 2.6 billion units in 2006. According to Research and Markets ( 2007 , 2009 ) and Plimsoll Analysis Confectionery ( 2011 ), the UK confectionery market achieved year-on-year growth to reach a value of £4.83bn in 2009.

The confectionery market can be divided into two broad sectors: chocolate confectionery (including countlines, blocks, boxed chocolates and bite-size prod-ucts), and sugar confectionery (including fruit sweets, mints and chewing gum). Chocolate confectionery accounts for nearly three-quarters of sales by value. Countlines continue to account for the largest share of the sector but boxed assort-ments are showing the fastest growth.

17.2.2 Use of packaging in the confectionery industry Confectionery represents a major market for food packaging, especially folded cartons. Examples of confectionery packaging can be found in Fig. 17.2 . The total value for carton-boxed confectionery in the sales during the 16-week period

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Robotics and automation for packaging in the confectionery industry 403


before Christmas was 40% of the total. The value of carton-boxed confectionery from one factory alone was £12 million for that period in 2007. The manufacture of products to be sold during this period takes 4–5 months and the manufacture of products for Easter sales takes 3 months.

Figure 17.3 indicates that confectionery represents a major market for cartons in the UK food market, with sales of about 2.4 billion units in 2001, which grew by 8% to 2.6 billion in 2006. The usage of other packaging methods, for instance bags, however fell by 4%. On the other hand, the usage of films continued to grow in this period by 14%.

17.2.3 Business requirements and commercial viability Seasonal products and other gifting products, such as those supplied to hotel chains, give the manufacturer and retailer a higher margin per kilo product than all-year-round (AYR) products. Consumers appear willing to pay a premium for these products because they are seen as unique and special purchases. However, as these products are seasonal and seen by the consumers as unique, their pack-

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Fig. 17.1 UK consumption of packaged confectionery. (Source: Packaging Machinery Technology, 2007 .)

Fig. 17.2 Variety of confectionery packs.

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aging is changed regularly. Different packaging formats are required for different customers and therefore production runs tend to be small.

In the confectionery industry, manufacturers are limited in the range of car-ton types that can be used by the carton erecting and packaging machinery they possess. Usually this machinery is limited in the types of carton format it can erect and hence all new cartons require the development and manufacture of new machines or new tooling for existing machinery. New tooling is also required for each different pack size and format used. The development and manufacture of such tooling can be very expensive and increases the confectionery manufac-turer’s lead time for introducing new products to market. This therefore reduces the manufacturer’s ability to react to changes in the demands of their custom-ers. Tooling change-over, when changing production from one packaging format type to another, also adds cost to the confectionery manufacturer. In conven-tional machines, even dealing with a size change, more than 40 adjustments are required and can only be done manually (Dai, 1996a , 1996b ; Cannella and Dai, 2006 ). During any change-over the machine is unproductive, and in most cases after the change-over, the machine requires a tuning period before full produc-tion can commence. This again reduces productivity (Dai, 1996a , 2005 ). Adding to the problem, most packaging machines are based on the 1950s and 1960s technology, largely using pneumatic actuators that are difficult to reconfigure as in Fig. 17.4 .

The alternative to use of machines is manual erection of cartons. This is a more expensive process, adding cost to the final product, particularly when an expen-sive seasonal labour supply is required. These manual workers must go through an expensive induction and training programme to teach them to erect a carton. Training and practice are required for each different pack type and the nature

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Fig. 17.3 UK market for confectionery usage of packaging by product sector. (Source: Packaging Machinery Technology, 2007 .)

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of short runs and small batch production means that re-learning is required fre-quently for relatively short periods. The speed and quality of the carton erection process is reduced when compared to that of a dedicated machine, and waste is often increased greatly. As such, the manufacturer generally expects approxi-mately 2% packaging reject from a carton erecting machine, but the initial stages of training operatives to manually erect complex cartons is likely to reach up to 35% material wastage. After training, this figure is likely to settle down to between 10% and 15% wastage. As packaging is, on average, 35% of the finished product cost, this adds a significant sum to the production costs for the confec-tionery manufacturer. A number of other problems are associated with the use of manual labour as follows:

• Social problems: production is often geared to meet seasonal requirements (e.g. Easter eggs and Christmas production) and this results in recruitment problems and subsequent unemployment. • Labour injuries: repetitive motion causes injuries to human fingers and wrists, and the sharp edges of paper and carton material cause cuts to human fingers and hands. • Hygiene: this is a subsequent problem – for example if labour injuries lead to bleeding into the production area then the producer is required to carry out a complete deep clean of the production line.

Fig. 17.4 A conventional packaging machine.

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It has been verified that in some industries such as the confectionery indus-try (Dai, 1996a ; Dunn, 2006 ) reconfigurable packaging machines (Dai, 2006b; Dubey and Dai, 2006 , 2007 ) are the means of achieving a flexible production to reduce the expensive costs of seasonal employment and to tackle the afore-mentioned problems. The machines are expected to be reconfigurable in order to adapt to different types of cartons and to follow different procedures for various closing methods. It has been suggested (Dai, 1996b ; Dai and Caldwell, 2010 ) that this reconfigurability can be spread into a number of stations so that both productivity and utilisation can be increased. In this arrangement, with a higher productivity and reduced complexity resulting in reduced cost, the benefit from this technology is overwhelming. The cost saving can be illustrated from a case study. The cost of employment of ten seasonal workers is around £180 000 with annual inflation rate of 2.5% for subsequent years. In comparison, the cost of a reconfigurable machine that can complete the same task as ten workers is esti-mated as approximately £180 000. The payback is 10 months. The other quan-tifiable benefits include employment, wastage reduction, health and safety, and hygiene.

Of course one of the difficulties in designing any form of cartoning machin-ery is that cartonboard is a highly non-linear material (Dai and Cannella, 2008 ; Beex and Peerlings, 2009 ). It is possible to model some forms of carton behaviour (Hicks et al ., 2001 ; Dai and Rees Jones, 2002 ). Nonetheless the usual design strat-egy is to try to ensure that the worst cases are catered for. A number of research-ers have considered various forms of board folding. This includes paper folding (Song and Amato, 2004 ; Balkcom and Mason, 2008 ), as well as origami carton folding (Dai and Cannella, 2008 ; Dai and Caldwell, 2010 ).

Typical confectionery packs such as origami packs, which do not require the use of solvents in packaging, need a dexterous and reconfigurable machine with robotic fingers (Dubey and Dai, 2006 ; Luo and Dai, 2006 ; Dai and Caldwell, 2010 ) to produce packs with sufficient variety and complexity to attract custom-ers. The demonstrator system in this chapter makes use of two forms of mecha-nism. There are basic folder units for making the folds around pre-defined creases (Dai et al ., 2009a; Yao et al ., 2010 ), and finger mechanisms for guiding carton faces in the appropriate direction. A number of finger mechanisms have appeared in the literature (e.g., Liu and Dai, 2003 ; Birglen and Gosselin, 2006 ; Luo and Dai, 2006 ; Wei and Dai, 2009 ) with varying numbers of degrees of freedom and hence potential application areas. Constraint modelling techniques were used for part of the design and simulation work for the demonstrator. These allow the design to be built up from what is known initially about the constraints, with the model being expanded as the designer’s confidence increases and knowledge about the design task becomes greater (Mathews et al., 2006; Mullineux et al ., 2010 ). Constraint-based design is frequently used in this way (Mullineux, 2001 ; O’Sullivan, 2002 ; Hoffmann, 2005 ; Mattthews et al ., 2006 ). The constraint modelling environment that was used makes use of optimisation techniques to resolve constraints (Hicks et al ., 2006 ), although other approaches are possible (Hoffmann, 2005 ; Michelucci and Foufou, 2006 ).

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17.3 Reconfigurable mechanism technology Reconfigurable mechanism technology is particularly applicable to the confec-tionery industry because of the variety of confectionery products that are packaged and the need for quick change-overs between different products. The extended reconfigurability and the versatility of machines using this technology would enable the machines to adapt to different packaging requirements and ensure the machines are fully utilised.

17.3.1 Introduction Reconfigurable mechanisms have been a research trend since the 1990s (Dai et al., 2009b; Dai et al ., 2012). Mechanisms with a changeable topology (Kuo et al ., 2009 ; Zhang and Dai, 2009 ) and a metamorphic process (Dai and Rees Jones, 1999 ; Gan et al ., 2010 ; Zhang et al ., 2010 ) have been investigated. Confectionery packaging presents a new scope for reconfigurable mechanisms and their study (Dai et al ., 2009b ; Dai et al., 2012). The development of machine reconfiguration for the confectionery industry requires research into carton-folding techniques and machine adaptability. Lu and Akella ( 2000 ) at the Beckham Institute used fix-ture techniques to describe carton folding based on a conventional cuboidal car-ton and used the similarity between carton motion sequence and robot operation sequence for operation. But the technology only focused on rectangular cartons. Though some machine prototypes have been produced to handle more complex cartons, these machines often only cover a single type of carton (or possible very similar types) and so lack reconfigurability. Dai and Rees Jones ( 2002 ) took a new approach and used an equivalent mechanism to describe a cardboard carton, this generates carton manipulation. Liu and Dai ( 2002 ) subsequently investigated carton manipulation and developed robotic fingers for carton folding. Dai and Cannella ( 2008 ) further revealed the characteristics of carton panels and creases during the folding motion that were used for the development of a novel pack-aging station. Neale et al . ( 2009 ) applied the constraint-based approach to the modelling and analysis of packaging machinery and to the creation of a new pack-aging machine. There have been opportunities for research on reconfigurable con-fectionery handling and packaging technology using the robotic finger principles (Yao and Dai, 2008 ) and constraint modelling (Mullineux and Matthews, 2010 ) to meet the business needs for confectionery handling and packaging.

17.3.2 Stages in the design and creation of reconfigurable mechanisms for confectionery packaging

The following stages were used for design and creation of reconfigurable mecha-nisms for confectionery packaging (Dai et al ., 2009a).

Work analysis The motion of packaging cartons for confectionery is critical for folding and erecting mechanisms and for automation. This needs a generic analysis (Dai and

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Rees Jones, 2002 ; Döring et al ., 2006 ; Hicks et al ., 2007 ; Yao and Dai, 2008 ; Wurdemann et al ., 2010a) of the geometry, kinematics and sequence. The motion analysis generates a profile that covers similar types of cartons and differentiates the cartons by their categories. This analysis leads to the design and development of reconfigurable mechanisms.

Modularity The system requires modular construction for diverse carton-folding functions including poking, tucking and squeezing operations using robotic end-effectors (Dubey and Dai, 2006 ; Wurdemann et al ., 2010b). The modules, in the form of either folders or fingers, can be designed through the common motion and manip-ulation of carton folding. In particular, the packaging unit needs to be modular in order to be arranged on the production line.

Reconfigurability The system needs to be capable of changing its modules by repositioning and reorienting them in the reconfigurable space, resulting in adaptability and ver-satility to suit multiple tasks. This can be realised by programmed motion and progress control and by mechanism reconfiguration. The position and orientation of modules varies with the shapes of cartons and their folding sequences (Dai, 1996b ; Dai et al ., 2009a; Zhang and Dai, 2009 ; Aminzadeh et al ., 2010 ).

Requirements The system needs to be designed to meet the requirements of customers and the constraints of the manufacturing environment. An automatic packaging process involves many subtasks. Generating physically valid folding sequences is the first to be considered (Liu and Dai, 2002 ; Song and Amato, 2004 ). The car-ton function is decomposed and the information is obtained from carton-folding analysis so that robotic fingers and folders can be designed. These modules are arranged in a lay-out by changing their positions and orientation for different cartons and folding functions. The flow chart of the analysis and synthesis is shown in Fig. 17.5 .

17.4 Case study of a reconfigurable system for carton folding

Reconfigurable packaging machines are the means to achieve flexible production and to reduce the cost of seasonal employment. A reconfigurable system (Dai et al ., 2009a; Yao et al ., 2010 ) was designed and produced to demonstrate the con-cept of reconfigurability and adaptability in food handling and packaging.

17.4.1 Reconfigurable demonstrator system The demonstrator system was created to handle a particular form of carton. This is a tray carton whose net is shown in Fig. 17.6 . The main base panel is considered

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as being fixed during the erection process. The four main faces need to be folded into the vertical position. Between these faces are four pairs of ‘gusset’ faces which move with the four main faces. The two end-faces are each attached to an additional rectangular face. The final stage in the erection process is to fold these over and into the tray. These then capture and retain the folded gussets and form double walls at the end of the completed tray. Tabs at the sides of the addi-tional faces fit into cut-outs on the longer side faces and ensure the completed tray remains erect without the need to apply glue. Trajectories of four gussets and of the main faces are shown in Fig. 17.6 .

Based on carton folding and common-motions analysis, the reconfigurable system was designed for the carton tray folding. What was found was that cer-tain faces of the carton net needed to be actively folded. Other faces followed passively, but these needed to be guided to ensure that they moved in the correct direction. Modules were created to show the reconfigurability of a robotic system for carton packaging. There were two types of modules designed to help fold the faces of the carton: robotic fingers (Yao and Dai, 2008 ; Yao et al ., 2011 ) and folder mechanisms (Sirkett et al ., 2007 ; Mullineux et al ., 2010 ). The arrangement of the system is shown in Fig. 17.7 . The end-panels of the folder mechanisms make con-tact with the faces of the carton net and cause them to turn when required. The panels can be changed depending on the size of the corresponding carton face. Suction cups within the end-panels grip the carton face to ensure that no slippage occurs during folding. Suction cups are also used to hold the base of the tray fixed while the other faces are folded around it. The robotic fingers are used to guide the passive faces of the carton. An end-effector, which is essentially a thin blade, pushes on the appropriate crease and moves with it as the carton erects around it.

These modular fingers and folders are arranged on a base and can be moved appropriately depending on the size and design of the tray carton to be erected.

17.4.2 Prototype of reconfigurable system for folding carton trays As part of the design process for the reconfigurable demonstrator, prototypes of the basic robotic finger and folder mechanism were created and tested. This

Fig. 17.6 Folding trajectories of the faces and gussets of the tray carton.

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enabled the appropriate motors to be selected and tested. It also ensured that sat-isfactory speeds could be obtained and that the torques created were sufficient to deal with the expected range of cartons. The fingers were designed to achieve planar motion with two degrees of freedom. This means the motors need to move together in a pre-determined relation. The folder consists of two folder sub-units. The sub-units are essentially the same and allow rotation about a single (vir-tual) axis. One sub-unit is sufficient to fold the long-side faces of the tray car-ton. Mounting one sub-unit on another allows the two folding operations on the end-faces to be achieved.

In the final demonstrator system, the modules are mounted on an aluminium structure system that was built from extruded aluminium beams (of modular design) together with framework connectors and sliding elements. The system can be assembled quickly and economically using only hand tools. The structure also enables additional components to be easily integrated, such as pneumatic cylinders, sensors and cables.

17.4.3 Motion control for the demonstrator system The demonstrator system made use of servo-motors and there is a need to estab-lish the control signals for these to achieve the appropriate motions (Sahinkaya et al ., 2007 ). An experiment was undertaken to make sure the timings of the var-ious operations were correct. Since vacuum cups were used to hold several of the faces of the carton net, sufficient time delays needed to be in place to ensure suf-ficient grip was obtained before folding took place. The experiment was designed to test the performance of the automatic packaging system. Figure 17.8 shows the flow chart of the process.

Carton

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Fig. 17.7 Arrangement of modules for tray folding.

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At the start of this experiment the carton was sucked onto the base platform at the centre of the system. Fingers stand below the gusset corners and the ori-entation of the fingertips is along the creases of the gusset corners. Folders are arranged along the creases of the wall-panels.

Figure 17.9 shows the timing sequence for tray cartons. The cycle time was 0.81 s, with a speed of 72 packs per minute. Synchronisation between the motors was another important factor, particularly for the finger modules where the posi-tion of the end-effector is determined by the position of its two motors. Each fin-ger should stand under the base of the tray. The first step of the fingers should be to move up and break the crease of the gusset corner, in the interval 0–0.21 s. This manipulation is controlled by one motor. The second step is to push the broken gusset corner into the right position. This manipulation is controlled by the other motor. At the same time the ‘lower folders’ rotate 90° to fold and support the four side faces. After that the ‘upper folders’ rotate 180° to fold the double wall into its final position, requiring 0.4 s.

Peaks occur during the movement of the end-effectors of two fingers from the end position to the start point. The design of the fingers means that these manipu-lations are more difficult than the folder’s manipulation.

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Fig. 17.8 Flow chart of the experiment.

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17.4.4 Testing of the demonstrator system An experiment was carried out in a demonstrator constructed (Dai et al ., 2009a) based on Fig. 17.8 with reconfigurable modules. The general arrangement is shown in Fig. 17.10 . Inductive sensors are used to mark the zero positions of the motors in order to avoid position errors.

The folding process is shown in stages in Fig. 17.11 . In Fig. 17.11a , the pick-and-place unit extracts the next carton net from the supply stack. It moves it across to the erection unit ( Fig. 17.11b ), places it there and then moves away ( Fig. 17.11c ). In the version of the system shown, fixed ‘crease breakers’ are used instead of the fingers to initiate the breaking of the gusset creases as the net is placed onto the erector. The folder units act to erect the carton tray, and the erected form is seen in Fig. 17.11d . The pick-and-place unit then approaches the erected tray ( Fig. 17.11e ), contacts it ( Fig. 17.11f ) and then moves it to a conveyor. The total cycle is 30 units per minute, which compares well with the time achieved for manual erection. The model-based approach is used for co-operating two folders and two double-folders (Liu et al., 2008).

The system is able to fold tray cartons of different sizes (with the same basic geometry) by changing the positions of the mechanism’s modules. The advantages of the system include that the system enables more reconfigurable and flexible solutions, especially for seasonal production, and reduces the cost for overcharges on packaging assembly line with its modular design.

In this process the velocity and acceleration for every position segment is gen-erated automatically (Quin Systems, 2001). The speed is limited by the maximum speed of the system. These maps are extracted from the timing diagram for the angular motion of fingers. This control was successfully demonstrated in the test rig and proves the manipulation planning strategy.

The strategy consists of four steps: modelling the carton and generating the motion trajectory, manipulating the trajectory in the interactive space,

Pick-and-placeunit

Conveyor

Control unit

Folders

Fig. 17.10 A demonstrator in an industrial environment.

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establishing a timing diagram of the motors, and linking the motion trajectories to controllers by maps.

It has been verified in confectionery manufacture that the reconfigurable pack-aging robotic system is able to reduce the expensive costs of seasonal employ-ment and tooling change-over. The cost saving can be illustrated from a case study in a manufacturer in the United Kingdom (Yao et al ., 2010 ) as in Section 17.3 .

17.5 Future trends The future trends are for flexibility and reconfigurability in the context of small batch production, which entails short runs and frequent change-over. This presents scope for research and development of reconfigurable mechanisms and machines (Dai et al ., 2009b; Dai et al., 2012 ).

17.5.1 Reconfiguration Research and development work has indicated the potential of reconfigurable systems with respect to confectionery packaging. The automatic reconfigurable confectionery handling and packaging system arising from the work described in this chapter can enable the confectionery industry to further exploit the seasonal confectionery market. It also allows leaner production, reduces rejection rates and downtime and increases market opportunities. Between 10% and 30% of packag-ing waste would be reduced if the manual erecting of packaging could be replaced with a reconfigurable system. A reconfigurable system could be exploited in sev-eral ways. One way would be by providing a means whereby end-users can per-form the reconfiguration for themselves (e.g. via software). An alternative would be to provide a service for end-users in which the specification for reconfiguration

Fig. 17.11 Folding cartons by the demonstrator in an industrial environment.

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is provided based on the details of the packaging design. There is scope for pro-viding these details electronically and/or via internet communications.

As mentioned above, reconfiguration techniques particularly benefit indus-tries where variety and seasonal changes are required. In cases where the man-ual erection and closure of cartons is not economically viable and existing machines cannot adapt to the new product, the techniques developed and the machine prototype produced can provide a means of creating new products for growing markets. An example from the confectionery industry is the supply of confectionery to hotel chains where mini-bars require special confectionery products with forms of packs and assortment changing frequently. The use of reconfigurable-machine technology could potentially result in an increase in output/sales by confectionery manufacturers. In general, the current research and development of reconfigurable machines benefits the industry from machine making to food production and to food distribution. The technology is capable of being extended to other food manufacturing sectors and the idea of recon-figurability provides an opportunity to enhance food manufacturing. This will lead to improvements in working conditions and levels of employment and so help social and economic sustainability. Further, the concept of reconfigurabil-ity would lead to future development of machines based on the new technology. The potential market in the United Kingdom for the machine can be envisaged to be 5–10 machines per year, which represents up to £1.5 million. Also, possi-ble savings on waste can be somewhere between £3000 and £10 000 per pack-ing line per year.

17.5.2 Reduction of environmental impacts Since the research described above is aimed at the food and confectionery indus-try, most of the targeted packaging has a functional quality that is more important than its appearance or suitability as a gift package. Its chief function is to get the product to market in good condition, thereby reducing wastage.

The research into reconfigurable-machine technology should have no negative environmental impacts. On the contrary, there are some other significant environ-mental benefits. These include:

Reduced level of material wastage compared with hand erected packaging. • Use of fewer machines than alternative solutions, and hence power savings. • Better transport/storage costs. Pre-glued hand-assembled cartons take up more • space than flat machine-erect blanks that are used in this project. If glues that contain solvents are avoided, it is easier to recycle packages. Flat • blank machine-erect-cartons usually need a smaller area of carton board than pre-glued cartons. Improved health and safety aspects. Less personnel involvement automatically • reduces the accidents, RSI potential, burn injuries associated with working with hot glues and cut injuries from sharp edges of cartons. The quicker and more efficient size-changes also reduce material wastage. •

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Generally, packaging accounts for between 10% and 35% of the total cost of • the product in the confectionery sector. This is already a huge cost to the man-ufacturer who is trading in a market driven by price promotion. The incentive is for the manufacturer to reduce the packaging cost, rather than to go for over-packaging of items.

17.6 Conclusion The confectionery industry is a highly competitive market where reconfiguration technology is needed to meet the demanding requirements of short runs, small batch production and frequent change-overs for a vibrant and demanding consumer market. Automation and robotics technology are hence leading the research in this industry particularly in the end of production lines for packaging of packaged confectionery products. This provides wide scope for researchers to use the reconfigurable mecha-nisms and robotics technology and to develop reconfigurable machines.

This chapter further presents this challenging market and the pressing task associated with developing and using reconfigurable-machine technology; it also describes a reconfigurable robotic demonstrator system with a design based on the strategy of reconfigurability and developed in a factory. This reconfigurability technology helped to create a reconfigurable production line that meets the chal-lenges faced in the confectionery and food industry.

17.7 Acknowledgements The demonstrator system described in this paper was created as part of a research project funded by the Department of Environment, Food and Rural Affairs (Defra) and the Engineering and Physical Sciences Research Council (EPSRC) of the UK under its Advanced Food Manufacturing LINK Programme in a collabora-tion with the University of Bath (Professors Tony Medland and Glen Mullineux) and a group of industrial companies including Bendicks Mayfair Ltd (Ms Evelyn Weddell), Quin Systems (Mr Mike Webb), and Marks and Spencer (Dr Mark Caul). This funding and support are gratefully acknowledged. Contribution to the demonstrator from Dr Wei Yao, Dr Ferdinando Cannella, Dr Lei Cui and Dr Guowu Wei of King’s College London is gratefully acknowledged. The author further acknowledges the financial support of the European Seventh Framework ECHORD project DEXDEB under grant number 231143 and in particular thanks Prof. Glen Mullineux for his friendly check of the manuscript.

17.8 References Aminzadeh , V. , Wurdemann , H.A. , Dai , J.S. , Reed , J. and Purnell , G. ( 2010 ) “ A new

algorithm for pick and place operations ,” Industrial Robot: An International Journal , 37 (6), 527 –531.

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http

://w

ww

.woo

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dpub

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ngon

line.

com

M

onas

h U

nive

rsity

(76

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-440

)

Tue

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2, 2

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Balkcom , D. J. and Mason , M. T. ( 2008 ) “ Introducing robotic origami folding ,” The International Journal of Robotics Research , 27 (5), 613 –627.

Beex , L. A. A. and Peerlings , R. H. J. ( 2009 ) “ An experimental and computational study of laminated paperboard creasing and folding ,” International Journal of Solids and Structures , 46 , 4192 –4207.

Birglen , L. and Gosselin , C. M. ( 2006 ) “ Kinetostatic analysis of underactuated fingers ,” The International Journal of Robotics Research , 25 (10), 1033 –1046.

Cannella , F. and Dai , J. S. ( 2006 ) “ Crease stiffness and panel compliance of carton folds and their integration in modelling ,” Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science , 220 , 847 –855.

Dai , J. S. and Cannella , F. ( 2008 ) “ Stiffness characteristics of carton folds for packaging ,” Transactions of the ASME: Journal of Mechanical Design , 130 (2): 022305_1 –7.

Dai , J. S. ( 1996a ) “Survey and business study of the dextrous reconfigurable assembly and packaging system: DRAPS – CREF reconfigurable production plant,” Research and Project Report , PS960321, Unilever Research.

Dai , J. S. ( 1996b ) “ Conceptual design of the dextrous reconfigurable assembly and pack-aging system: DRAPS – CREF reconfigurable production plant ,” Research and Project Report , PS960322 , Unilever Research.

Dai , J. S. ( 2005 ) “ Automatic reconfigurable confectionery handling and packaging sys-tem ,” Food Link News , 53 , 10 – 11 .

Dai , J. S. and Caldwell , D. G. ( 2010 ) “ Origami-based robotic paper-and-board packaging for food industry ,” Trends in Food Science & Technology , 21 , 153 –157.

Dai , J. S. and Cannella , F. ( 2008 ) “ Stiffness characteristics of carton folds for packaging ,” Transactions of the ASME: Journal of Mechanical Design , 130 , 022305:1 –7.

Dai , J. S. , Medland , A. J. and Mullineux , G. ( 2009 a) “ Carton erection using reconfigu-rable folder mechanisms ,” Packaging Technology and Science , 22 , 385 –395.

Dai , J. S. , Zoppi , M. and Kong , X. W. ( 2009b ) “Editorial preface in reconfigurable mecha-nisms and robots,” Proceeding of the ASME/IFToMM International Conference on Reconfigurable Mechanisms and Robots (ReMAR 2009) , KC Edizioni , June.

Dai , J. S. , Zoppi , M. and Kong , X. W. (2012) “Preface,” Reconfigurable Mechanisms and Robots I, Springer, London, July.

Dai , J. S. and Rees Jones , J. ( 1999 ) “ Mobility in metamorphic mechanisms of foldable/erectable kinds ,” Transactions of ASME: Journal of Mechanical Design , 121 (3): 375 –382.

Dai , J. S. and Rees Jones , J. ( 2002 ) “ Null-space construction using cofactors from a screw-algebra context ,” Royal Society of London Proceedings Series A , 458 , 1845 –1866.

Döring , U. , Brix , T. and Reeβing , M. ( 2006 ) “ Application of computational kinematics in the digital mechanism and gear library DMG-Lib ,” Mechanism and Machine Theory , 41 , 1003 –1015.

Dubey , V. N. and Dai , J. S. ( 2006 ) “ A packaging robot for complex cartons ,” Industrial Robot: An International Journal , 33 (2), 82 –87.

Dubey , V. N. and Dai , J. S. ( 2007 ) “Complex carton packaging with dexterous robot hands.” In Huat , L.K. , ed., Industrial Robotics: Programming, Simulation and Applications . Mammendorf, Germany : pro Literatur verlag Robert Mayer- Scholz/Advanced Robotics Systems International , pp. 583–594.

Dunn , J. ( 2006 ) “ It’s chocs away as flexibility takes flight – new research aims to develop packaging machinery that combines automation with flexibility ,” Food Manufacture , 29 March 2006, in the news, also available in http://www.foodmanufacture.co.uknews/fullstory.php/aid/3059/It’s_chocs_away_as_flexibility_takes_flight.html

Gan , D. M. , Dai , J. S. and Liao , Q. Z. ( 2010 ) “ Constraint analysis on mobility change in the metamorphic parallel mechanism ,” Mechanism and Machine Theory , 45 , 1864 –1876.

Hicks , B. J. , Medland , A. J. and Mullineux , G. ( 2001 ) “ A constraint based approach to the modelling and analysis of packaging machinery ,” International Journal of Packaging Technology and Science , 14 (5), 209 –225.

Cop

yrig

hted

Mat

eria

l dow

nloa

ded

from

Woo

dhea

d Pu

blis

hing

Onl

ine

D

eliv

ered

by

http

://w

ww

.woo

dhea

dpub

lishi

ngon

line.

com

M

onas

h U

nive

rsity

(76

5-47

-440

)

Tue

sday

, Mar

ch 1

2, 2

013

7:14

:49

PM

IP A

ddre

ss: 1

30.1

94.2

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Hicks , B. J. , Medland , A. J. and Mullineux , G. ( 2006 ) “ The representation and handling of constraints for the design, analysis, and optimization of high speed machinery ,” Artificial Intelligence for Engineering Design, Analysis and Manufacturing , 20 , 313 –328.

Hicks , B. J. , Mullineux , G. , Berry , C. , McPherson, C. J. and Medland , A. J. ( 2007 ) “ Energy method for modelling delamination buckling in geometrically constrained systems ,” Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science , 217 , 1015 –1026.

Hoffmann , C. M. ( 2005 ) “ Constraint-based computer-aided design ,” Journal of Computing and Information Science in Engineering , 5 , 182 –187.

Kuo , C. , Dai , J. S. and Yan , H. ( 2009 ) “Reconfiguration principles and strategies for recon-figurable mechanisms,” ASME/IFToMM International Conference on Reconfigurable Mechanisms and Robots (ReMAR 2009), 22–24 June, London, UK .

Liu , H. and Dai , J. S. ( 2002 ) “ Carton manipulation planning using configuration transfor-mation ,” Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science , 216 (5), 543 –555.

Liu , H. and Dai , J. S. ( 2003 ) “ An approach to carton-folding trajectory planning using dual robotic fingers ,” Robotics and Autonomous Systems , 42 (1), 47 –63.

Liu , H. , Dai , J. S. and Seneviratne , L. D. ( 2008 ) “ A model-based approach to cooperative operation of multirobot systems ,” Industrial Robot: An International Journal , 35 (1), 37 –45.

Lu , L. and Akella , S. ( 2000 ) “ Folding cartons with fixtures: A motion planning approach ,” IEEE Transactions on Robotics and Automation , 16 (4), 346 –356.

Luo , Z. and Dai , J. S. ( 2006 ) “ Geometric analysis and characteristics of a three-fixed-pivoted multi-phalanx robotic finger ,” Journal of Mechanical Engineering Science , 220 , 1075 –1082.

Matthews , J. , Singh , B. , Mullineux , G. and Medland , A. J. ( 2006 ) “ Constraint-based approach to investigate the process flexibility of food processing equipment ,” Computers & Industrial Engineering , 51 , 809 –820.

Michelucci , D. and Foufou , S. ( 2006 ) “ Geometric constraint solving: The witness config-uration method ,” Computer-Aided Design , 38 , 284 –299.

Mullineux , G. ( 2001 ) “ Constraint resolution using optimisation techniques ,” Computers & Graphics , 25 (3), 483 –492.

Mullineux , G. , Feldman , J. and Matthews , J. ( 2010 ) “ Using constraints at the con-ceptual stage of the design of carton erection ,” Mechanism and Machine Theory , 45 , 1897 –1908.

Mullineux , G. and Matthews , J. ( 2010 ) “ Constraint-based simulation of carton folding operations ,” Computer-Aided Design , 42 , 257 –265.

Neale , G. , Mullineux , G. and Medland , A. J. ( 2009 ) “ Case study: Constraint-based improvement of an overwrapping machine ,” Journal of Engineering Manufacture , 223 , 207 –216.

O’Sullivan , B. ( 2002 ) Constraint-Aided Conceptual Design , Professional Engineering Publishing Limited , London .

Quin Systems ( 2010 ), Putting Imagination into Motion , available at: http://www.quin.co.uk/, accessed February 2011.

Packaging Machinery Technology ( 2007 ) “Confectionery,” Larger Confectionery Pavilion to Make Pack Expo in 2007, Dusseldorf.

Plimsoll Analysis Confectionery ( 2011 ) “A comprehensive study of the UK Confectionery market in 2010,” Plimsoll Publishing Ltd.

Research and Markets ( 2007 ) “Snapshots UK Confectionery 2007,” Snapdata International Group.

Research and Markets ( 2009 ) “Confectionery Market Report Plus 2009,” Key Note Publications Ltd.

Sahinkaya , M. N. , Rayner , R. M. C. , Vernon , G. , Shirley , G. and Aggarwak , R. K. ( 2007 ) “Synthesis of demand signals for high speed operation of a packaging mechanism,”

Cop

yrig

hted

Mat

eria

l dow

nloa

ded

from

Woo

dhea

d Pu

blis

hing

Onl

ine

D

eliv

ered

by

http

://w

ww

.woo

dhea

dpub

lishi

ngon

line.

com

M

onas

h U

nive

rsity

(76

5-47

-440

)

Tue

sday

, Mar

ch 1

2, 2

013

7:14

:49

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ss: 1

30.1

94.2

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Proceedings of 2007 ASME International Design Engineering Technical Conferences & Computers and Information in Engineering Conference, IDETC/CIE , Las Vegas , paper DETC2007–35444.

Sirkett , D. M. , Hicks , B. J. , Singh , B. , Mullineux , G. and Medland , A. J. ( 2007 ) “ The role of simulation in predicting the effect of machine settings on performance in the packag-ing industry ,” Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering , 221 , 163 –176.

Song , G. and Amato , N. M. ( 2004 ) “ A motion-planning approach to folding: From paper craft to protein folding ,” IEEE Transactions on Robotics and Automation , 20 , 60 –71.

Wei , G. and Dai , J. S. ( 2009 ) “ Geometric and kinematic analysis of a seven-bar three-fixed-pivoted compound-joint mechanism ,” Mechanism and Machine Theory , 45 , 170 –184.

Wurdemann , H. A. , Aminzadeh , V. , Dai , J. S. , Reed , J. and Purnell , G. ( 2010 a) “ Category-based food ordering processes ,” Trends in Food Science & Technology , 22 , 14 –20.

Wurdemann , H. A. , Aminzadeh , V. , Dai , J. S. , Reed , J. and Purnell , G. ( 2010 b) “ Introducing a new 3D ordering process for discrete food products using food categori-sation ,” Emerald Group Publishing Limited, Industrial Robot: An International Journal , 37 (6), 562 –570.

Yao , W. and Dai , J. S. ( 2008 ) “ Dexterous manipulation of origami cartons with robot fin-gers based on the interactive configuration space ,” Transactions of the ASME: Journal of Mechanical Design , 130 , 022303:1 –8.

Yao , W. , Dai , J. S. , Medland , T. and Mullineux , G. ( 2010 ) “ A reconfigurable robotic folding system for confectionery industry ,” Industrial Robot: An International Journal , 37 (6), 542 –551.

Yao , W. , Cannella , F. and Dai , J. S. ( 2011 ) “ Automatic folding of cartons using a reconfig-urable robotic system ,” Journal of Robotics and Computer-Integrated Manufacturing , 27 (3), 604 –613.

Zhang , K. , Dai , J. S. and Fang , Y. ( 2010 ) “ Topology and constraint analysis of phase change in the metamorphic chain and its evolved mechanism ,” Transactions of the ASME: Journal of Mechanical Design , 132, 121001 .

Zhang , L. and Dai , J. S. ( 2009 ) “ Reconfiguration of spatial metamorphic mechanisms ,” Transactions of the ASME: Journal of Mechanisms and Robotics , 1 (1), 011012_1 –8.

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robotics and automation in the food industry || robotics and automation for packaging in the...

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