Limitation of end effector movements

Depending on the configuration and the instructing function block, different parameters with different priorities have a limiting effect on the resulting end effector motion.

For all parameters, the value valid at the time of instruction always applies (rising edge at the FB input Execute ).

The following parameters are available:

All parameters are maximum values. Thus, depending on the motion profile, it is possible that these values are not reached. Which parameters act with which priority depends on the type of the instructing FB (see the following sections).

Limitations for Cartesian path movements (CP)

(concerns MC_MoveLinearAbsolute , MC_MoveLinearRelative , MC_MoveCircularAbsolute ,
MC_MoveCircularRelative )

For Cartesian path movements, the limitations act with the following priority:

  1. Path velocity, path acceleration and path jerk are first limited by the parameters Velocity , Acceleration , Deceleration and Jerk applied to the instructing FB.
  2. If these values are higher than the limitations set for the axes group, the movement is limited to the lower value in each case.
    The limitations set for the axes group are:
    • Path velocity ( 45 )
    • Path acceleration ( 46 )
    • Path jerk ( 47 )
    The limitations must be set with a value ¹ 0.
  1. The limitations ( 45 ... 47 ) set for the main axes of the axes group are considered as soon as the respective axis is involved in the movement.
    Please note that
    • the limitations are set with a value ¹ 0 and
    • the limitation of the main axes has been activated with the parameter 40 .
  1. Considering the maximum axis velocities and axis accelerations of the X, Y and Z axis, the following applies:
    • In case of linear motions, the path movement is limited with regard to the respective path distance of the axis so that no axis involved exceeds its limitation but at least one can reach its maximum value.
    • In case of all other motions accurate to path, it is limited to the lowest parameter of all single axes involved.
  2. Limitations in the (real) drive axes are not considered during the path planning with Cartesian motions.
Limitations for point-to-point motions (PTP)

(relates to MC_MoveDirectAbsolute , MC_MoveDirectRelative )

In case of point-to-point motions, always the fastest possible synchronous motion of all real axes is driven subject to its individual limitations ( 40 , 41 and 43 ). The end effector motion arises from the resulting motion profiles of the real axes by means of the current kinematic transformation. Limitations of the axes group and the Cartesian main axes are not considered in this motion profile.

Limitations for single-axis motions on axes of an axes group

(relates to MC_MoveAbsolute , MC_MoveRelative , MC_MoveVelocity , ...)

In case of single-axis motions, only the limitations of the respective axis are considered. Limitations of the axes group or other axes of the axes group are not considered.

Limitation of the positioning motion of the end effector

The three parameters available in the axes group ( 45 ... 47 ) limit the positioning motion of the end effector.

  • If an FB is instructed to execute a Cartesian path motion (CP) with higher values for Velocity , Acceleration , Deceleration or Jerk , these values are automatically reduced to the values available in the axes group at the time of instruction.
  • The limitation only acts on the motion of the end effector along the instructed path.
  • If one of these parameters has the value 0, it is ignored and the parameter applied to the FB is used.
Limitation of the rotary motion of the end effector

The three parameters available in the axes group ( 31 ... 33 ) limit the rotary motion of the end effector.

  • The parameters Velocity , Acceleration or Jerk set at an FB for instructing a Cartesian path motion (CP) only define the translatory profile parameters.
  • For the rotary motion, the values ( 31 ... 33 ) available in the axes group are used, reduced, if required, to the respective maximum values of the involved orientation axes A, B or C
  • The limitations only act on the motion of the end effector along the instructed path and refer to the rotational axis in the axis/angle representation.