Going paperless is one start-point of the digital revolution in manufacturing, known by many as the Smart factory, or Industry 4.0. By Michael Ford, Aegis Software
Since our early ancestors first started drawing on the walls of caves, the physical entity of the ‘canvas’ and the way of marking shapes, symbols and pictures has, of course, evolved massively in comparison to the technology of printed matter today.
The move to ‘paperless’ however is not just the next stage of this evolution. There is a far more profound paradigm shift moving physical media into the digital domain that paperless technology provides, which is a critical component of our digitalised Smart factory. The future of ‘Paperless Manufacturing’ is far more than simply manufacturing without paper.
The Hidden Costs Of Paper In Manufacturing
Paper is not without its merits. It is not dependent on any form of batteries or power supply and does not need to be in the range of any Wi-fi or Bluetooth signals. If the paper is stored correctly, it can last for hundreds of years without any of the issues we have seen related to changes in digital media storage. Paper is still seen by many as a matter of permanent record.
There are unfortunately some key restrictions and costs. Paper can normally only be read by one person at a time. You have to find the paper in order to be able to read it. There is an easy way to copy what is on the paper, but then the version control of information becomes harder to manage. These issues may sound trivial until we take into account costs related to, for example, ISO document management and certification which has become a significant part of industry requirement.
The cost of managing data on paper is far higher than people imagine. Storage of billions of manufacturing documents is not a fiction. Even when the paper document with needed information is located, there is often the task of extensive manual searching through the document. Paper can often be misplaced or lost. Information can be changed or removed.
There is the difficulty of managing the content of what is written on paper, with errors in consistency, meaning and interpretation. The language is also fixed. One has to wonder what the total cost of paper-based documentation in manufacturing really is, after all, as soon as someone suggests the replacement of paper with a paperless system, all eyes are suddenly focused on the cost of the technology of the replacement, rather than the cost of the legacy operation.
There are two sides to the use of paper within manufacturing. Paper is commonly used as a way to communicate work-instructions for manufacturing processes, whether manual or automated and for things such as logistics and maintenance instruction. The second use of paper in manufacturing is to record information about things that have happened, whether that is production event records or the history, for example, of maintenance actions performed. The first use of paper brings information into manufacturing, and the second takes information out. The digital replacement of paper, therefore, requires two separate though related approaches.
Data-flow into the factory starts with the product design description. Though information such as drawings or lists of information can be communicated electronically, for example, sent by email, it should be noted that receiving a scanned document or diagram as communication of information is only a small step in reality towards being paperless, as the document is either printed or interpreted on-screen as if reading a paper document. There is a little further value from the digitalisation of the information, as the content is not digitalised, only the way in which the data is transferred.
In production, converting paper-based product model data into the various forms of process model data requires a huge manual repetitive engineering effort. For automated processes, such as SMT machines, the result is often in the form of a machine program, though more generally the output is a dataset that describes the individual work assignments to each machine. The automated machine vendor software will directly interpret the data to then create optimised programs.
Automated processes do require, however, operator interaction, especially during the changeover, setup and material verification. Using paper for the guidance of tasks is very common. Non-automated processes, especially manual assembly of PCB components and final mechanical product assembly requires far more complex operational guidance documentation. For inspection and repair stations also, significant amounts of paper reference materials exist.
There are two key issues then related to the use of paper to deliver work-instructions. The first is whether the documents provided are up to date, and the second is how to know whether anything has actually changed. Many manufacturing operations issue paper-sets for each work-order, in which case it is very difficult to know whether there are changes buried in the detail. Others issue paper-sets only in the case where engineering changes have occurred, in which case it is difficult to know in the absence of new documentation whether updated documentation is not needed or is late or even lost.
Significant control and skill is required. For material logistics, where the paper is used for ‘pick-lists’ to control the movement of materials from point to point, these can often get lost or damaged. For product tracking, the paper ‘lot follower’ is used to describe the intended product process sequence, with paper repair tickets used to facilitate exceptions. Recording data from the factory operations is less complex, but often far less well managed.
Though many production processes are automated, when considering all of the processes, the majority are still manual, and so dependent on paper communication meaning that most data is still summarised and written down by operators. Recording events on an individual production unit basis is often impractical other than a simple stick-on repair ticket, which has a high risk of loss as repairs are made. As the requirement for data collection from assembly operations increases, significant operator distraction results which reduces their productivity dramatically. The data written is often subjective, which varies from operator to operator and their mood at the time, making such data collection of very little value and certainly not timely.
Paperless ‘State Of The Art’ Today
True digital technologies, such as the IPC-2581 format, can be used to digitally describe a product in production engineering terms within a single data file without the need for supporting drawings or lists of information. This allows software modelling to create a ‘digital twin’ of the product, that is, the complete product representation such that any aspect of the product data can be accurately viewed and digitally processed for any purpose. New Product Introduction (NPI) software takes this data and converts through digital simulation, together with the local bill of materials information and process specifications, into production process ready data.
The same digital twin model works to support manual assembly and test processes. Being digital, standard templates can be used which immediately create any required electronic documentation required for operation, assembly, change-over, setup, material loading etc. which can then be managed and displayed by an MES system at the various points in production where required.
Typically, in most cases today, low-cost PCs and terminals are used at key stations that display electronic documentation. The advantages that the best MES computer systems can provide include specific and contextual control and display of information, ensuring compliance and version control, even highlighting any subtle but important changes that have occurred since previous versions.
In the same way, maintenance tasks and material logistics can also be provided in electronic format. The use of hand-held mobile devices is recommended for such an approach as the knowledge and instruction is related to the operator as they move around, rather than the location at which they are working. The same terminals, whether static or mobile can also be used to gather data collected from the processes.
Unlike paper recording, the best MES software can assist data entry using data entry wizards that ensure data is collected quickly and accurately following rule-sets that drive consistency and avoid mistakes. The use of standard digital fault codes etc. means that data collected is not language dependent. It can be for example that data is input in Spanish or Chinese, with reports made for example in English or Japanese.
Replacing paper documentation with true digital documentation provides the opportunity for automated documentation management, as well as increasing data accuracy and timeliness. The ‘digital twin’ of product information and ‘digital shadow’ of production history existing together on a manufacturing MES platform provides a great deal of additional benefits. Any piece of data can be used for many different purposes. The calculation of key metrics for performance, quality etc. can be made and displayed so as to provide an opportunity for operational improvements on dashboards and in reports. These are based on live data collection prior to the data being sent remotely into for example a cloud database.
The tracking of products on a single unit basis can also easily be supported, ensuring that all processes are executed in the correct order, including the managed routing through additional inspection and repair processes where potential defects have been detected. Data can then also be used to augment key decision-making at the whole factory level, for example assisting with decisions of planning, work-order allocation and scheduling based on the actual live throughput, status, material and resource availability.
The provision of a single source of accurate and timely flow of information means that all roles in the factory, whether production, engineering or quality related see the same key information contextualised according to their role, which is complete and consistent with the other viewers.
The best results are obtained where an MES solution has live data links with all automation as well as providing electronic documentation terminals for assembly, with feedback, plus the inclusion of critical supporting transactional operations such as materials logistics and resources, all on the singular platform. Digitalised MES in this way can today remove every instance of the requirement for paper in mainstream activities across the operation.
The Future Of Paperless Manufacturing
Looking forward, there are two key areas of technology that are being developed. The first is related to the methods and devices associated with the way in which we view electronic documentation and how that documentation is presented. Assembly operators, for example, today have to look away from their work towards a computer screen for instruction, which is a distraction. It can create quite a strain on the neck, hands and eyes continuously moving back and forth.
Using Augmented Reality (AR), for example, a digital headset or glasses will soon be able to provide a heads-up display for the operator while they are working. This eliminates losses of time and concentration. The latest Bluetooth v5 has, for example, adequate bandwidth and signal strength to provide complex, real-time instructions to AR headsets which presents assembly, inspection or test information step by step to the operator in real-time as they work. This technology will even present live pointers and guidance for the operator, superimposed on the physical work that they are doing, reducing learning time and almost eliminating the risk of mistakes, even when the product or work-order changes.
For high-mix cell-based Lean production, such technology is likely to have a significant impact. Operators will become more productive and less stressed, with throughput increased in some estimates by as much as 50 percent.
The second area of technology being developed is within the advanced digitalised MES software itself. Advanced algorithms are currently used to convert disparate data elements into added-value key metrics. These algorithms will start to evolve into Artificial Intelligence (AI) algorithms, that will be able to go further working out ways to enhance and optimise production in real-time, even to the extent of automatically introducing new products, adjusting production quantities and timing to suit changing customer needs. Initially, this will take the form of assisted decision-making, where AIs will create suggestions and options from which management and engineering can choose. As AIs become more advanced, and trusted, decisions to be made or confirmed by human management will no longer be needed.
To enable these AI algorithms to get to this level of effectiveness, the digital twin model of the product and digital shadow of the production data must be complete and accurate. Collecting data from the many machines from different vendors is currently limited by the sheer number of different communication content format definitions.
Within 2018, it is expected that this limitation will start to change as a new Industrial IoT standard, such as the upcoming Connected Factory Exchange (CFX) standard from the IPC, is adopted by machine vendors, manufacturers and solution providers.
Very soon, digital factories will be achievable for all sizes of companies in any sector of the industry. The productivity of such factories is expected to increase significantly, though the main benefit will actually be the high degree of flexibility, being able to handle extremes of product mix, without penalty on productivity. Going paperless is one start-point of the digital revolution in manufacturing, known by many as the Smart factory, or Industry 4.0. Actually, digital manufacturing is a very real, business-driven effort, that all factories need to embrace.