Dynamic production environments require close cooperation between humans and robots without rigid separations. The Dynamic Safety system developed by Botfellows enables great flexibility while maintaining a high level of safety, thereby facilitating efficient cooperation between humans and robots. Botfellows is a spin-off from the Fraunhofer IWU in Chemnitz. Dynamic Safety is available in two versions, the functionality of which differs according to the requirements.

The core version of Dynamic Safety is a flexible safety module for fenceless robotics. The module is compatible with a wide range of common safety sensors, including 3D radar and 2D lidar. It dynamically calculates compact safety zones and then automatically configures the safety sensors. This makes it easy to implement efficient, fenceless robot applications, even in dynamic production environments. With the Dynamic Safety Advanced variant, the system differentiates between moving persons and inanimate objects. Thanks to the direct connection to the robot controller, the system continuously processes real-time movement data and uses this to determine the minimum required safety zones in accordance with the applicable standards. At the same time, it permanently monitors the positions of all people and objects in the shared workspace. This enables safe and efficient collaboration without physical separation devices. If a person approaches the defined danger zone, the robot slows down or stops immediately.

At least 30 percent less space required

Dynamic Safety works with both light robots and heavy-duty robots. It continuously collects data on the machine's status, including speed, position, force and acceleration. The safety areas are defined as warning and protection fields, which are determined and monitored in real time. An intelligent algorithm evaluates the collected data, recognizes potentially dangerous situations and takes into account possible effects on the surroundings. If a critical situation arises, human safety is the top priority. The system reacts immediately and automatically adjusts the speed to reliably avoid risks.

Robots equipped with Dynamic Safety no longer require fixed safety fences. Instead, they use flexibly adaptable virtual safety zones. Conventional rigid safety zones usually limit the shared workspace of humans and robots to mere coexistence. The robot detects people

and reacts to them, but cannot actively support them. Dynamic Safety brings a decisive step forward here by allowing direct collaboration between humans and robots as a team. Dynamically adapted safety zones create new scope for task distribution and combined work processes. This reduces the space required by at least 30 percent, and even more in the case of comprehensively networked systems. This is made possible by the considerably faster reaction time of the robot controller. The robot can stop instantly in the event of danger, making more efficient use of the available space. The result is higher capacity utilization, greater system availability and more productive working time overall.

Higher performance with high-level language code

In its search for an open and powerful hardware and software platform up to SIL 3/PL e, Botfellows came across the safety controllers in the PLCnext Control product family from Phoenix Contact. The PLCs stand for open and free programmability of automation solutions. In addition to the standardized IEC 61131 languages, high-level languages such as C/C++/C#, Matlab Simulink or Python can also be used in a real-time context.

Safety-relevant functions can also be executed in C and used as a library in the PLCnext Engineer engineering environment. Botfellows offers highly specialized function blocks for the fenceless protection of agile robot applications with dynamically changing protected areas. These function blocks can be flexibly parameterized in combination with the recipe handling of the safety controller and can therefore be used generically for a wide variety of use cases and robot types.

In addition to openness, the safety control system from Phoenix Contact offers high performance. Analyses accompanying the development of the implementation of Dynamic Safety in C language compared to existing variants in Structured Text show an increase in performance by a factor of 5.

New business models from licensing to maintenance

Technology providers such as Botfellows can therefore use the PLCnext Technology ecosystem not only as a platform for technical implementation, but also for new business models. In addition to marketing and licensing via the PLCnext Store online platform, they also benefit from all maintenance and servicing functions such as device and update management for safety-relevant software and firmware components as well as application programs and parameters.

The safety controllers in the PLCnext Control series support the Profisafe and Safety over Ethercat (FSoE) safety protocols for connecting network-compatible safe sensors and actuators. An additional safety-relevant connection to a higher-level safety controller can also be implemented via Profisafe. This multi-protocol capability results in a high degree of flexibility when selecting the sensors and actuators that can be used for Dynamic Safety. In addition to their performance aspects, the components can also be selected according to their price-performance ratio and availability. The high-level language algorithms of Dynamic Safety are network-independent and can therefore be used generically. PLCnext Engineer is a powerful tool for programming standard and safety functions and for configuring and parameterizing Profisafe and FSoE networks.

In open control systems such as PLCnext Control, the increased security requirements are of particular importance. All safety controllers from Phoenix Contact are protected by the security measures implemented by PLCnext Technology and are certified for use up to security level SL 2 in accordance with IEC 62443-4-1/4-2. The functionally safe functions of third-party manufacturers such as Botfellows also benefit from this.

DynamicSafety@PhoenixContact thus proves to be a harmonious combination of the functionally safe, open hardware and software platform PLCnext Technology and the highly specialized technology functions for dynamically changeable fenceless safety zones from Botfellows.

Authors:

Steffen Horn, Head of Functional Safety, PLCnext Technology and Automation Systems, Phoenix Contact

Mohamad Bdiwi, CEO and Co-Founder Botfellows and Team Leader Collaborative Robot Systems, Fraunhofer IWU; Sebastian Krusche, CTO and Co-Founder Botfellows

SPS, Hall 9, Stand 310