Robots are an integral part of Industry 4.0, and they have shaped the sector. You might even say they have conquered it. As of 2017, there were around 1.8 million industrial robots worldwide. And, according to the International Federation of Robotics (IFR), that figure will rise by another 1.7 million by 2020. In many industries, factories and production facilities have become smart factories, self-learning and supported by robots. Collaborative robots, or cobots, enable a completely new kind of collaboration within smart factories. These machines work right beside humans, with no barriers between them. To ensure safe human-robot collaboration, adequate safety systems are required. In the future, these systems will be equipped with integrated safety functions based on embedded solutions, allowing additional safety functions while simultaneously increasing the level of integration.
High-Precision Assistance in the Process Industry
Demographic change, a lack of skilled specialists, and the demand for increased productivity necessitate the use of robots. And collaboration between humans and machines unites the best attributes of a worker. It combines the hand-eye coordination, power control, and independent problem-solving abilities of humans with a robot’s precision, trajectory control, and tirelessness. While robots are most prevalent in the automotive industry, the coworkers made of metal and wires have also found their way into the process industry. For example, Italian detergent manufacturer MARKA works with cobots. A robotic arm screws caps onto the chemical company’s products. “Due to the shape of the cap, it was difficult to get a grip and precise positioning. The reason we chose a collaborative robot from Universal Robots is because it was able to do precisely that,” says Sergio Melite, a specialist technician at MARKA.
Four Methods for Safe Collaboration
Performing heavy work requires power. But finding the right level of precision requires control. A cobot can do both – as long as it is correctly configured. To ensure the machines do not harm their human colleagues, companies need to follow the regulations in the ISO standard. This sets out four techniques that can be used for collaboration:
- Hand guidance: When a human and a robot share a workspace for collaboration, and there is physical contact, the robot is guided manually through the use of a joystick or a force-torque sensor, for example. The robot may only move at a controlled speed.
- Safety-rated monitored stop: When humans and robots coexist, they either work in different workspaces or at least do not work at the same time in the same workspace. The robot stops before the human enters the collaborative workspace and only restarts once they have left.
- Speed and separation monitoring: Human and robot work together in simultaneous, sequential, or parallel collaboration when they share a workspace, but no physical contact occurs. The machine moves at a reduced speed, and sensors monitor the separation distance between robot and human. If the minimum separation distance is violated, the robot automatically stops.
- Power and force limiting: The power of the robot is limited mechanically, electronically, or by sensors – as is the force of a collision. This technique is suitable for any form of collaboration between human and machine.
Without safety monitoring of robots, safe collaboration is practically impossible. Accidents such as what happened at a Volkswagen factory in Kassel, Germany, belong in the past. In 2015, a worker lost his life because a robot was not sufficiently secured. An error caused the machine to grab the worker and fatally crush him against a metal plate.
Robots Are Targets for Hackers
Functional safety technology by itself is not sufficient to protect employees from their new coworkers. If robots are connected to the internet, they are a possible target of cyberattacks. Once hackers gain access to the inner workings of a machine, they can use it to spy or to cause harm to people and products in the area. At CEBIT 2017, there was a convincing demonstration of just how easy that can be. Controlled from Hanover, a robot in a factory 600 kilometers away knocked over a stack of boxes. This example shows that cyberattackers can exploit security vulnerabilities to use robots for their own purposes. And in reality, the consequences are unlikely to be as harmless as few toppled boxes.
In a 2017 test, employees from U.S. cybersecurity company IOActive hacked into a NAO robot and an industrial robotic arm from Universal Robots and disabled the emergency mechanisms of the machines. This would then render safety techniques like hand guidance and force limiting useless.
The TÜV-Certified Coworker
Secured by the right technologies, cobots can change the industrial working world. But certification for these artificially intelligent assistants still presents an obstacle. From risk assessment and safety concept development to safety checks, it is a lengthy process to obtain approval to work with robots from the likes of TÜV.
One way to accelerate this procedure is to implement pre-certified embedded solutions for safety and cybersecurity. Even if a modification is carried out, it is not necessary to reapply for certification. This enables fast deployment of a wide variety of robotic systems.