Robots protected with wireless safety

Wireless Safety, an aluminium safety fence, emergency stop buttons and a safety door locking device, SSP not only supplied everything from a single source, but in this case also offered a coherent safety concept for the automation of a robot system. The demonstration cell consists of a robot, a carrier for the car body and a linear axis on which the robot moves. The cell is used exclusively for the demonstration of Sword Brushes.

Robot behind aluminium safety fence with Safety Simplifier safety controller and tGard as solenoid interlock

Safety linking of the systems as a challenge

From a safety perspective, the safety linking of the linear axis and the robot as well as the many accesses was the biggest challenge. "Linking the safety functions with the wireless safety control "Safety Simplifier" from SSP was many times easier for us than with conventional systems and we were able to flexibly expand the system, for example for safeguarding the windows."

Decentralised safety PLC with Wireless Safety

Because, the Plug & Play solution brings safety to where it is needed. SSP offers the decentralised safety PLC with Wireless Safety with 14 safe, digital inputs and outputs and optionally with two additional, double relay outputs. The user can then configure the 14 I/Os as desired and flexibly as inputs or outputs. For this solution, modules with 14 I/Os were selected for each door unit; the modules on the control cabinets also have two additional relay outputs to switch off the robot and machine potential-free. The door modules are also directly equipped with the necessary operating elements such as emergency stop and illuminated buttons. These can also be freely selected via an online configurator. The integrated LED display enables a quick overview of the inputs and outputs and provides further information on signal strength or number of participants.

Safety Simplifier on the robot safety controller

Wireless control Safety Simplifier

Wireless communication

Above all, this new concept also drastically reduced the wiring effort of the system, because the tGard safety interlock and external emergency stop buttons are simply connected directly to the Safety Simplifier with pre-configured connectors. This means that no additional safety PLC or wiring effort is required in the control cabinet. The Safety Simplifier now sends the signals wirelessly on a frequency of 2.4 GHz to the other participants in the system. The special feature here is that it is not a simple transmitter and receiver model, but through mutual multi-master communication, a comprehensive network of safety communication is established, in which each Safety Simplifier also serves as a repeater. This means that even longer distances can be bridged reliably and quickly without the use of cables! If Wandres decides to use Safety Simplifiers on additional installations, there are still 15 channels available on the 2.4 GHz frequency so that they do not interfere with each other. In total, up to 16 Safety Simplifiers (256 I/Os) can communicate with each other in one system.

Safety interlock tGard

It is self-explanatory that the highest safety requirements are necessary for such an application, which is why SSP solenoid interlocks are used on the access doors. The solenoid interlocks from the Fortress Interlocks - tGard range are particularly robust and, due to their slim design, are perfectly suited for mounting on an aluminium fence. A mounting plate is no longer required.

Safe control

In addition, the user can benefit from a decentralised safety concept at the same time. Simple functions can be easily added to existing as well as new systems. Functions such as "door closing" or "time-delayed opening" can be selected and directly connected to the safety outputs of existing safety systems and machine controls. A control cabinet for the safety technology and a higher-level safety switching device are no longer necessary in this case.

Solenoid interlock tGard and emergency stop button EDI