Using the «LAxesGrpCtrl» block library for controllers in the Siemens SIMATIC S7-1200 family, it is possible to coordinate and traverse multiple axes of a Cartesian handling system on a predefined motion path as a synchronous point-to-point (sPTP) movement in space.
Using the blocks in the library, it is very easy to implement traversal movements of the Tool Center Point (TCP) from point P1 in space to a second point P2 in space in a Cartesian kinematic system.
f more than two points in space are chained to form a coherent movement, the intermediate points in the movement can be assigned a blending radius. Once the traversal movement has come within the defined radius from the intermediate point, the movement path will be blended: The next point in space will be approached.
Thus, before it approaches the next point in the path, the Tool Center Point (TCP) follows a path through the blending radius which is not precisely defined but rather which depends on the programmed dynamics values.
The coordinated traversal movement of the axes in a Cartesian kinematic system results from the individual motions of the kinematics axes via the motion control function «MC_MoveAbsolute» to the next target position. Here, the dynamics of the individual motions are adjusted by the blocks in the library in such a way that all axes start simultaneously and, if at all possible, reach the target position simultaneously.
The duration of the traversal movement of the slowest axis in the kinematic system is calculated, then the dynamics of the remaining axes are reduced so that all axes need the same amount of time for the traversal movement.