How to... find opportunities in collaborative automation

Materials World magazine
,
1 Aug 2018

Phil Webb, Cranfield University, UK, looks at automation and the potential of humans collaborating with robots.

One only has to look at any recent media coverage of robotics, automation, or artificial intelligence to realise that not only are there significant advances in technological capability, but also equally important societal and attitudinal challenges to what is sometimes misleadingly referred to as the rise of the robots. The perception of the job-stealing robot is becoming more prevalent, as it is clear that they will have an impact on working life. 

By embracing new forms of automation and robotics, there are many opportunities for industry, and particularly smaller companies, to realise significant productivity gains, increase growth and, in many cases, employment. However, if these groups do not grasp these opportunities then there is grave risk of losing employment not to robots themselves, but to other businesses and nations that have seized the opportunities presented. One such significant and much vaunted new technology is collaborative robotics. 

What is it and what does it mean?

Collaborative robotics allow a human operator to be closely integrated into an automation system as opposed to being physically excluded from the entire process – as is normal with more conventional robotics and automation. In truly collaborative robotics, a human and robot, or other automated system, work together on the same task in the same workspace at the same time. An alternative to this is cooperative robotics, in which the operator and robot work together on the same task in the same workspace, but sequentially. So what are the advantages of collaborative and cooperative robotics? 

Firstly, they allow the automation of many processes that would previously have been prohibitively expensive to do by leveraging the skill of the human operator to handle variability. Secondly, they are often easier to implement at lower cost due to the different and flexible guarding requirements needed to ensure safety. 

The release of safety requirements for industrial robots (ISO10218-1 and ISO10218-2) in 2011 was a turning point with a number of changes that recognised the advances that had occurred in robot and controller technology. For instance, it allowed the use of force and torque limited manipulators without physical guarding. It also permitted the presence of operators in the working envelope of standard industrial robots, with the controller running in automatic providing it was equipped with the relevant safety monitoring capability. The standard is currently being revised and it is anticipated that its replacement will enable greater opportunities for co-working. 

Until recently, robots capable of working collaboratively were limited to what are commonly referred to as cobots, but this is a misnomer as in reality any robot can be used collaboratively depending on the application. In many cases, it is the end effector or process tool that is the source of most danger to operators rather than the manipulator itself, making its safety irrelevant. Typically, these cobots are limited to maximum payloads of 10kg, as above this the force torque limitations will be exceeded. 

There is now a new and more interesting class of robot emerging that is capable of significantly exceeding these payloads, one example being the Fanuc CR35-ia (above). Similar robots are now being produced, or planned, by most of the major robot manufactures, opening up a huge new applications domain. These newer collaborative robots operate within the safety standards by using advanced sensing to detect any physical contact and react accordingly.

Challenges to implemention

There are many challenges to using automation, but they can be broadly divided into understanding, acceptability, and business case. To use any robot collaboratively we need to understand its capabilities alongside the proposed application. A fundamental question can be, does it really need a collaborative robot or would a more standard approach be better? 

Collaboration is most effective when there are clear boundaries that can be identified in the appropriate demarcation of effort between the human and robot. Consideration must be given to each of the individual tasks and what the tacit skill requirement is from the human or, for instance, the repeatability of the robot. A typical example of an effective application is in complex assembly tasks where the collaborative robot can be used to position and hold parts while the human operator completes the installation, eliminating the cost of expensive tooling and allowing rapid reconfiguration for different product variants. Furthermore this can be scaled up using the new higher payload robots, removing the need for manual handling or simplifying the manipulation requirements for larger subassemblies. 

Tasks that require more aggressive processes, such as welding, are best performed cooperatively with the operator excluded from the workspace during the hazardous operation. This strategy can also be adopted for the manipulation of large parts during assembly that have masses in excess of the capability of collaborative robots. 

The second and often most intractable challenge is acceptability both at management and operator levels. It is imperative that engagement takes place at an early stage and all parties have direct experience of working with these robots during development to build trust and acceptability. Unsurprisingly, recent work has shown that young workers with little experience of industrial robots adapt far more positively than those with greater experience. It is true that there is an element of complacency through lack of knowledge, but this must be carefully managed as proximity to any moving machinery presents dangers. However, a key differentiator is often that they have fewer preconceptions of what is conventionally regarded as safe and not safe and do not have formative historical experiences of working with earlier industrial robots that could be unpredictable and highly dangerous. 

Thirdly, it is well known that the UK is relatively poor at investing in automation, even when factors such as greater servitisation in the UK economy are taken into account. In the case of the low payload force and torque limited robots, their use can often provide a lower cost entry point through relatively easy programming and the reduced need for complex protection and safety systems.

There are clear opportunities ahead for the widespread and closer integration of people and robots in the workplace, which should be enhanced by the introduction of new standards. As we move forward we need to consider the true role of robots in the workplace and even closer coupling with people – for example, exoskeletons. This is raising significant ethical concerns that are now being formally considered by the standards bodies. What is clear is that the workplace will be a very different environment in the future and UK industry must adapt if we are to continue to prosper.