Digital Twin Or How To Reduce Products Development Time
The high-tech company Grenzebach’s portfolio includes the simulation of material flow in complex plants in the glass industry. To achieve this, Grenzebach uses Siemens simulation solutions. Together, the two companies have developed the most recent product from Grenzebach, the tin-air speed stacker, a machine for stacking all types of glass sheet. This expertise has produced a Siemens digital twin for the first time as well as the motion control. This allowed all the functions and permutations of the stacker to be simulated while simultaneously developing the initial motion control program to provide an optimum starting point for virtual commissioning. By running what were previously sequential development steps in parallel, it was possible to reduce both development times and costs significantly.
The tin-air speed stacker is a three-axis rapid stacker which can selectively pick up glass sheets from the tin side or the air side and rapidly place them vertically on a glass rack – up to 20 times a minute. This represents a 30 percent improvement in stacking performance and makes the tin-air speed stacker the most powerful stacker in its class. The motion control is provided by a Simotion D445 motion control system with the Handling Advanced universal library as well as Sinamics S120 modular converters and Simotics S servomotors. Grenzebach was venturing into completely new ground with this development. “In order to get to grips with the potential singularities of the kinematics which were similar to those found in articulated robots, we decided to build a digital twin for the first time,” explains Roland Jenning, Head of Innovation at Grenzebach.
Erring on the side of caution
The digital twin was produced using the NX Mechatronics Designer software from Siemens PLM Software. The initial motion control programs were created at the same time as the digital twin which reduced the development time and time to market significantly. To make the simulation of the programmed movements in the digital twin as close to reality as possible, Grenzebach chose a ‘hardware in the loop’ design in which the control is connected to the kinematic modal in NX via a Simit simulation unit. The program is then tested using the Simotion Scout engineering system; Simit picks up errors and highlights weak points. This allows processes to be optimized long before the first actual commissioning. However, this is not the end of the digital twin’s usefulness. Future modifications to the plant or changes to the product can be played out virtually in advance and checked for errors without disrupting continuous operation.