One of the main doubts regarding collaborative robots concerns protections: being designed to work in contact with operators, can cobots be used without additional protective measures?

Before answering this question, it should be made clear that no cobot is collaborative a priori: it is the application and programming that makes a robot ‘collaborative’. This means that the use of protective devices depends on the specific application.

EN ISO 10218-1 sets out the requirements for robots for collaborative applications:

• Monitored safety stop: the robot must stop or slow down to a standstill when the operator is within the collaborative space. This condition must be maintained and monitored
• Manual guidance: the robot must be able to be manually guided by means of an appropriate device to transmit movement commands
• Speed and distance monitoring: the robot’s speed and distance from the operator must be constantly monitored to ensure operator safety
• Power and force limitation: the robot must be programmed to limit the power or force applied by the robot in the event of contact with the operator to avoid injury or pain.

This last point implies two potential scenarios to be evaluated when analysing a collaborative application: the impact force is not dangerous for the operator and the impact force is dangerous for the operator.

In the first case, it is possible to design a collaborative application without perimeter guards or other protective measures. To this end, measures may be necessary for the correct determination of the limit values reached by the cobot.

In the second case, however, it is necessary to prevent the operator from coming into contact with the cobot while it is still in motion. Although this can be guaranteed even without the use of perimeter guards, it is still necessary to provide other protective devices, such as photoelectric barriers, laser scanners or suitably positioned radars, so that the area around the cobot can be monitored.

At Advolo, we provide you with a team of experts in the field of robotics who can assist you from the design of your robot island according to the main reference standards to certification in accordance with the applicable product directives. Do not hesitate to contact us for more information at: commerciale@advolo.it