Safety concepts for free-moving mobile systems
Depending on the risk assessment, movements must be evaluated by a safety controller and stopped if the safe boundary conditions are violated.
The safety technology of a mobile system enables safe operation in an industrial environment in which people are present.
The safety concept must be designed in such a way that the mobile system reliably detects people and obstacles and switches to a safe state in good time in the event of an impending collision.
At the beginning of development, a hazard and risk assessment should be carried out in accordance with the applicable standards. Depending on the risk assessment, the respective (motion) state of the mobile system must be reliably detected. Encoders, switches and other sensors (condition sensors) that meet the required performance level are used.
Safe laser scanners are used in mobile systems for environmental perception. These safety laser scanners can monitor several safety zones with different dimensions at the same time.
The safe input variables of the state sensor determine which safety zone is evaluated at which motion state. For example, a smaller safety zone in front of the vehicle can be used during slow travel than during fast travel. The aim is to evaluate a precisely matched safety zone and thus maintain the availability of the mobile system while meeting the required safety requirements.
At the same time, the safety controller specifies the limits (acceleration values, maximum speeds, curve radii, braking ramps) and thus monitors the travel maneuvers of the "unsafe" vehicle controller.
Safety solutions by SEW-EURODRIVE allow for:
- Easy, centralized and clearly structured programming and parameterization
- Programming centered around a function block diagram, with the possibility of creating macros
- Wide range of connectivity options in the EtherCAT® network and Safety over EtherCAT® network
- Open safe and non-safe fieldbus interfaces to PROFINET/PROFIsafe
- With safe additional encoder monitoring, depending on the design
- Extensive diagnostics and debugging options
