Robots or Cobots – Which Technology Should You Choose?

Suppliers of industrial robots and cobots (collaborative robots) are regularly asked which is the best technology option for manufacturing. Indeed, the question was recently raised following a BARA (British Automation and Robot Association) board meeting. This gave rise to a discussion about the advantages, disadvantages and ideal applications which is covered here.

Defining Robots & Cobots

As highlighted in the Automate UK guide to robot types, industrial robots have traditionally been used for manufacturing purposes. Programmable and capable of movement across three or more axes, these robots offer benefits in terms of production line flexibility and efficiency. Also offering high precision and accuracy, industrial robots are typically used in place of humans for the performance of tasks categorised as dull, dangerous, and dirty.

Industrial robot types include the:

• Six-axis articulated arm - highly flexible and dextrous, six-axis robots are commonly used for applications such as IG & TIG welding, sealing & glueing, and machine loading
• SCARA (Selective compliance assembly robotic arm) - capable of exceptional speed and accuracy, SCARA robots are ideally suited to pick-and-place applications
• Cartesian - ranging in size and capacity, Cartesian robots are commonly used for de-moulding operations on Injection Moulding Machines
• Delta - with their distinct configuration, Delta robots operate at particularly high speeds and are well-suited to food and packaging applications.

Although cobots also come under the industrial robot category, they are designed specifically to work alongside humans (rather than replace humans). Cobots may be operated with minimal or light safety guarding, unlike their traditional robotic cousins. The integration of cameras and HMI (human-machine interface) units is common, with cobots allowing for better application of human capabilities. Cobot programming is also relatively easy, thanks to the recall and repetition of set movements.

Cobots are a particularly good choice where:

• Space is at a premium
• High throughput or force is not required 
• Processes involve the use of multiple robots and other production equipment
• Interaction with human operators is required

There’s some disparity in the sale and application of different robot types, with a reported 3.4 million industrial robots in use across the world. The global robotics industry is forecast to reach $43.32 billion in revenue by 2027, with the cobot market expected to reach $7.66 billion by 2030. Such widening adoption is likely to have a positive impact on manufacturing business growth, given the relative shortage of skilled manual labour.

Choosing Suitable Robotics

There’s an increasing tendency for manufacturers to assume that cobots are the best choice, with industrial robot suppliers commonly asked about their availability. Indeed, many suppliers have opted to offer cobots for positive engagement with prospective buyers. On-site discussions typically focus on suitability in terms of throughput, safety levels, reliability, and other key factors. Cobots may, or may not, be recommended depending on the established user needs.

The choice of traditional robots and cobots should be made in consideration of:

• The expected performance of tasks calling for different levels of precision, hazard avoidance, payload capacity, and throughput
• The required level of human-robot interaction, availability of space, and integration with existing systems in the work environment
• The budget (considering the initial investment and ongoing maintenance) and expected return on investment.
  

A risk assessment should be carried out before deciding on the best choice of robotics. This should account for key standards specific to robot selection and solution design such as ISO/TS 15066, ISO 10218-1, ISO 10218-2 and ISO 12100. Where cobots are concerned, this will mean accounting for potential human contact with areas of the robot such as the grippers or payload. Risk assessment findings may highlight the need for guard rails, safety sensors, and other means of human protection.

There should also be some allowance for the adjustment of application parameters. As an example, there may be a sacrifice in speed, with multiple cobots needed for the expected level of throughput. Alternatively, the desired throughput might be achieved through the implementation of an industrial robot with a safety cage. The key is to first look at the application and then the technology needed to achieve it.

For a clearer idea of the suitability of industrial robots and cobots, it’s worth reading the case studies in Machinery Update. As an example, the May/June 2024 edition focused on the collaboration between TM Robotics and Orfer in developing a compact robotic system which allows for the opening of flattened cases, with the flaps being folded and base sealed in a single cell (page 16). The July/August edition included an article about Epson’s launch of high-capacity six-axis SCARA robots designed for safe collaboration with humans (page 15).

Such case studies reflect the need for a structured decision-making process, involving:

• Assessment of business needs and goals
• Evaluation of task and environment suitability
• Calculation of budget and potential ROI
• Consultation with experts and vendors.

Expert Advice

To recap, robots and cobots come with a distinct range of advantages. There are a wide range of industrial systems, suitable for diverse applications such as heavy loading and pick and place. With cobots being introduced more recently, the range of applications is more limited (although expanding at a pace). Care must be taken over the choice of such systems according to your business capacity and need. It’s generally best to limit the scope of implementation and gauge feasibility in the short term.

Do you have experience or perspective on the suitability of robots and cobots for different applications? Go ahead and share with Automate UK on LinkedIn or X. or contact us to see how we can support you here.