Collaborative robots: Risks and rewards
14 February 2018
Jonny Grey, UK sales & marketing manager, Motoman YASKAWA, explains why he believes collaborative robots are a way to future-proof a manufacturing process
Having contemplated how to complete a challenging, tedious, and possibly dangerous job, there is usually a heightened sense of satisfaction when you actually get it completed safely. That sense of accomplishment probably will occur for the first few times. However, over time, these types of jobs are likely to become more tedious and could have a negative impact on operators, preventing them from spending time on higher value tasks. Installing an industrial robot to take over tedious or monotonous work may not always be the answer. That’s because not all robots are equal.
Industrial robots can be a complex solution, especially for small and medium-sized businesses and not every plant manager has the staff (or the resources to hire an integrator) to program a robot. Health and safety requirements will mean the robot's working area will need to be safeguarded to prevent potential injury to those working close by.
Depending on your application, you can overcome these challenges by hiring a special type of industrial robot – a collaborative robot, or cobot. A cobot is relatively lightweight and is designed to operate safely in close proximity to people. This can eliminate the need for safety curtains or fencing, due to the use of proximity sensors or force-limiting technology and with the proper application and risk assessment. It’s easily programmed through hand guiding, which allows a worker to move the cobot’s arm to each point in a job instead of the more time-consuming process of typing commands into a pendant.
Those with only a limited knowledge of cobots may refer to them as ‘fenceless robots’ implying that they are safe. However, if you are manufacturing knives with a fenceless robot, is an operator working nearby any safer because the robot is moving slowly? It’s all about evaluating the complete system.
Before investing in a cobot, conduct an appropriate risk assessment. There are certified experts in robotics to handle these risk assessments to ensure that the robot, the application and operators interact safely. Getting this chemistry right brings the dual benefits of a safe place to work and improved productivity.
Here’s an example we saw during a site visit. A cobot grabbed a part for a lifting mechanism out of a forming machine; inspected it using a 2D camera and then inserted the part into another nearby machine for polishing. As a result of this repetitive task the operator previously manning this station risked injury from back strain and, toward the end of their shift, wasn’t examining the piece as closely as at the beginning of the day. The cobot eliminated the risk of injury to the worker and ensures more consistent quality control.
Collaborative robots can work alongside humans and are easily configured. If a cobot comes in contact with an operator, it immediately stops to minimise or eliminate injury. If you decide to reconfigure your production line to handle a new product, a properly trained operator can re-program a cobot in just an hour or two.
If management wants to change the style or type of product its plants are producing, a collaborative robot is versatile enough to handle whatever changeovers are needed with minimal effort and time. Collaborative robots can also provide benefits in terms of safety, cost, quality and ROI, making them a feasible solution for the technical and economic challenges faced by supply chain organisations, no matter the industry or size.
An example is the MOTOMAN HC10 which has been developed by YASKAWA. It has been designed for applications which require a simple, easy and safe robotic solution to automating tasks that require working in close proximity to human operators. The cobots are designed to operate in PLC-controlled manufacturing systems, eliminate the need and the costs associated with physical guarding, and feature simplified built-in network safety IO.