# Combining the Advantages of Different Processing Solutions Using a Novel Motion Processing Approach
## 5 Combining Processes with Differing Solution Principles
### Switching between Motion Profiles for Different Process Solutions  
Two process solutions can be combined if they implement the same technological task in relation to the product. In the example processes, the task 'convey product from rest position A to B' is performed. Starting point and target point of the product as well as rest at both points are identical for both processes. For other process types, this boundary condition may not be given. The previously introduced motion processing approaches have different characteristics. In the case of discrete processing, it is assumed that there are areas where switching with non-optimal motion specifications has no negative influence on the process result. The process characteristics are not important in this case. The continuous switching principle can be used for processes where an interpolated value is close to the optimum value assigned to the given operating speed. Processes with basically different characteristics cannot be switched in this way. In this case, an excessive distortion of the interpolated motion compared to the optimal solution would induce instabilities in the process. In the example processes, as described above, different physical principles are used to implement the technical task. As a result, the motion profiles at the working tool differ considerably. Depicted in Figure 8a are the X-components of the motions. Figure 8b shows the motion as a 2D plot in the workspace of the kinematics. Since the motion in Y is the same for both processes, it is not considered further here. When comparing the motions, the following is worth mentioning:  
* Both motion profiles have an identical starting point in rest at \(\tau=0\) (\(v=a=0\)). Discrete switching is allowed at this point. * In the new process (light gray), the process stroke (\(\tau=0\) to \(0.4\)) is in X direction significantly shorter than in the conventional process (dark gray). As a result, switching the process solutions within the process stroke would lead to a distortion of the resulting motion set-points due to the strongly differing motion profiles. This, in turn, could induce process instabilities, which, however, must be avoided. Switching within the process stroke is therefore not allowed for the example. * The return stroke (\(\tau=0.4\) to \(1\)) is also different for both process solutions. It can be seen that with the conventional solution (dark gray), the comb moves in a negative direction directly after the end point of the process stroke, while the new solution  
Figure 7: Basic idea of the new hybrid processing solution. (**a**) Product’s positioning error for the conventional and (**b**) new processing solution. (**c**) Principle of combining the two processing solutions with the aim of increasing the maximum operating speed. (light gray) first moves in a positive direction. This is related to the positioning of the comb and the product. Whereas in the conventional solution the product is in contact with the comb in the positive X direction, in the new solution, it is positioned in the negative direction. To avoid a collision, the comb must first be moved in the other direction. Since the return stroke is not relevant to the process in the example, there is the possibility of switching between the motion profiles here. It is evident that the end points of the process stroke are far away from each other. Even here, there is no risk of collision when switching. The product is at the same position for both processes, and the working tool will not touch the product even in an interpolated motion. Switching with a weighting function is therefore permissible in the entire return stroke. It should be noted at this point that the decision about which regions of the process are relevant or not must be made individually for each process. It cannot be generalized. Discrete motion processing is successful in the given scenario when switching within the return stroke or at the common starting point. This has already been verified in various previous works [7; 16; 18; 19].