EMPLOYEES’S SAFETY WITH ROBOTIC CELLS
Those who work in automation and industrial robotics known that the innovation they propose with their technologies and machinery must comply with precise safety standards. According to the “Consolidated Act on Health and Safety at Work”, indeed, Whenever the use of robots and robotic islands is foreseen in the production cycle, workplaces must comply with precise safety criteria.
The international reference standard for the evaluation of the peculiar risks linked to the use of integrated industrial robotic systems with complete production lines and industrial robotic cells is the ISO 102018-2 legislation. It’s interesting to notice how said law does not take into account the risks deriving from noise and processes in place, such as fumes or radiation, but 'only' the robot-human interaction.
Wanting to summarize in a very concise way what the legislation addresses are the requirements of the perimeter protections and the types of stop, emergency or safety.
But let’s see in detail what nuances the concept of safety assumes in industrial robotics.
More safety with industrial robotics
When we talk about industrial robotics and safety, the topic can be discussed from three connected perspectives:
- The use in safety with robotic cells
- More safety of the environments in which are installed because they work in more risky job
- New control criterias of safety
not only robotic cells must be as safe as expected by law, but they are the tool to exponentially increase safety in workplaces. Using them in the most risky phases for the operator, automatically reduces the incidence of accidents at work. In connection to this, is important to also develop new skills among workers in occupational safety related to environments, laboratories, industries that are increasingly converting to robotics.
Robotic cells for risky tasks
In numerous industrial contexts, the operator is engaged in continuous, repetitive and boring work activities. For this reason, there is the possibility that, with the passing of the hours, his level of attention decreases and that, exactly for this reason, the probability of accidents increases.
It would be ideal to believe that through industrial automation e industrial robotics all risks of injury for the operator would be cancelled. The undeniable advantage is their maximum containment L’indiscutibile vantaggio è il loro contenimento massimo. However, if we consider that we can entrust automation with these types of tasks, we can certainly assume an increase in safety in the workplace, a decrease in accidents and, above all, an ennobling/evolution of human labor.
Industrial robots can do the most dangerous jobs that are harmful to human health. It is not only an assessment in terms of work accidents, in many cases disabling, but also a tool to 'preserve' the health status of a population of workers who will have to be operational until old age.
For a solid improvement in safety, the robot must be seen as a real collaborator to the human activity, a real tool for improvement. For instance, a more advanced area of research than we might think is studying the use of exoskeletons to help workers in tasks that involve very tiring positions for long periods of time.
Physical and laser barriers
Now let’s talk about the risks related to the use of robotic cells. Having within them a robot that has a considerable weight, size and acceleration, cells can actually pose a danger to the inexperienced or distracted operator who is supervising, maintaining or loading/unloading there or simply working in its proximity.
There’s more. The most integrated type of robot in cells is usually the antropomorphic robot, which is a robot that is not able, on its own, to understand what’s around it and if there are moving bodies in its range. This requires the integration of special tools.
This is the reason why robotic cells are normally protected by physical barriers that act as protective devices. These are perimeter protections consisting of metal cages that surround the entire cell and are intended to reduce or prevent access to the hazardous area. Entry into the work area is possible through an alarmed door only after the robot has been deactivated.
This, nonetheless, implies that to make the operator work in safe conditions, the cell must be temporarily stopped, taking useful time from the production flow. This explains why laser barriers are often preferred to perimeter.
Laser barriers are devices equipped with sensors that detect the presence of an unknown body, they stop or slow down the robot in action and restart it when the safety distance is restored. The advantage is obvious, because in this way production never stops. The robot cell is active without stopping and the operator can work in complete safety.
Further reflection on the subject of safety can be made on collaborative robots, the cobots. These are robots that allow the worker to operate safely without the use of barriers, either physical or laser. Contact with the operator is very close so as to allow the human presence in case of activities where it is required more manual dexterity. Opinion is divided on their safety: the world of research and development ensures high levels of protection from risks and accidents and in fact they are decreasing, however there are still no studies that establish their relationship with the use of robotic cells.
As integrators of industrial robotics solutions we know with certainty that an operator's exposure to the risks associated with dangerous tasks is greatly reduced when a robotic cell is introduced into the company. However, it is also important to avoid other types of workplace accidents related to the use of the cells themselves, which can pose a real danger if they are not adequately demarcated, as required by law, by protective barriers, whether physical or laser.