The growth of automation and the rising popularity of Industry 4.0 ‘intelligent’ tools are helping manufacturers produce more tailored solutions to customer requirements, particularly in high-tech sectors. A high level of customisation, however, inevitably raises new challenges around the role of people in the production process, particularly in terms of skills development and error reduction.
Assembly tool manufacturer Desoutter puts it like this: “In the past, an assembly worker was valued because he or she could perform the same task competently on the same line day after day. In today’s more flexible manufacturing environment, that same worker may be required to rivet body panels one shift and wire up a lighting system on the next. Traditional training in all of these skills takes time – and the pace of technological change can render such learning obsolete very quickly.”
The question then becomes: how can we ensure that modern assembly workers feel valued and competent, and can access the information they need to complete tasks efficiently and free of error? Enter the intelligent workbench.
Andy Minturn, strategic product manager at Bosch Rexroth, says that at the heart of any assembly task are “lean manufacturing techniques” and ergonomic design of the working area. He adds: “Key drivers within the industry are batch sizes of one, increased variants and efficiency, which means assembly systems now have to provide flexibility in order to meet productivity demands.”
Michael Heath, PivotWare team manager at Desoutter, agrees, adding: “As we see the need for complete customisation increasing, and to enable suppliers to provide unique products to their ever [more] demanding customers, production styles have to change. This new concept in manufacturing allows for complete flexibility, as processes, product differentiation and production rates can be changed very quickly and easily.”
In complex production environments that can’t be controlled by humans alone, he says, there are only really two options: “You could completely automate production by using robots and remove the human factor. The problem here is that in a high percentage of companies this isn’t possible, as robots do not have the same adaptability, dexterity or decision-making processes as humans.
“When this first option isn’t available, or the costs are too great, the other option is to provide the human worker with the necessary tools and equipment to enable them to complete their tasks reliably and with constant repeatability whilst removing the responsibility from them.”
Workbench technology
Minturn says that intelligent workstation technology can be defined as “interactive assembly systems that have the capability to guide an operator through an assembly process”.
Desoutter’s intelligent workbench version is called PivotWare. It is a process control platform that guides operators through a specific set of assembly tasks as part of an automated process. A graphic and textual display shows them exactly what tools to use, components to apply and where to fix them.
The system verifies that each step has been completed correctly before allowing the operator to move on. The platform is programmable by the customer using software tools provided, so responsiveness to changes in requirements is unhampered by any need for specialist intervention.
“This innovative concept in assembly guides the user through the complete production process, providing continuous feedback to them and the manufacturing execution system, guaranteeing all steps in the process are completed correctly with no fault forward,” Heath says. “The system also allows for data capture, mining and review, ultimately leading to machine self-learning, efficiency gains and increases in production utilisation.”
Bosch Rexroth’s ActiveAssist is a good example of how software developments are pushing the boundaries within manufacturing. ActiveAssist is a freely configurable piece of software that connects to the physical assembly system that is equipped with sensors, touchscreens, cameras and projectors.
The system identifies the workpiece by radio-frequency identification (RFID) or barcode and loads the required workplan immediately onto the monitor. The work instructions can then be projected directly onto the work surface using a projector and the correct grab container is marked. All information is ergonomically positioned in their field of vision. The system is also compatible with hardware components such as simple clutch tightening tools and smart tightening systems, which allow tightening parameters to be monitored and logged.
And so, the products in action: On a multi-product line in the Bosch Rexroth plant in Hamburg, Germany, 200 variants of a hydraulic valve product are assembled economically and with no retooling. The assembly line connects people, machines and products. It consists of nine autonomous intelligent workstations. By means of an RFID chip, the product is controlled independently by the assembly line.
The work steps required are displayed to employees on screens at every workstation. Modifications are not necessary. This increases productivity by around 10%. Kanban systems and ‘supermarkets’ only provide the parts that are actually required. The result is a 30% reduction in stock.
An app for fault and deviation management increases availability. All that is required for diagnostics is a smartphone or tablet PC. Each station recognises employees by means of a Bluetooth tag and adjusts the work area to the individual, including language, qualifications and font – automatically.
The interactive manufacturing system, collects, filters and visualises production data continuously. The employees see the information in real time and can quickly come up with necessary solutions, reducing downtime and boosting productivity.
Pushing the boundaries
As automation continues to create new roles and challenges, intuitive human-machine interfaces like PivotWare will become increasingly important, according to Desoutter: “Not only does this platform deliver improved quality, reduced rework and increased volume production in automated environments, it also supports validation and traceability.”
Heath describes intelligent assembly workbenches as “the next wave in disruptive technology” and “a new concept to enable significant increases in agility and flexibility in a production environment”. And this is where intelligent assembly benches come into their own: “They are enabling producers to realise the end goal of product customization, flexibility and agility by managing the quality and accuracy of every product.”
Minturn points out that intelligent assembly systems can be used to optimise processes and, particularly important in today’s highly competitive quality-driven manufacturing environment, provide process and parts traceability. These systems can also support employees in reducing the likelihood of human error and deliver maximum process reliability and productivity. He concludes: “By connecting the physical assembly workstations to the world of IT, with a completely networked, easily integrated and modular system it can allow, operators, supervisors and management access to a wealth of information about the performance to further optimise processes.”