Tilting solution
Application
A defined spatial angle can be reached by performing various rotary axes movements.
In order to achieve a certain solution, for example to avoid collisions, you can pre-position the rotary axes or program SYM (SEQ).
Description of function
In the optional machine parameter prohibitSEQ (no. 201209), the machine manufacturer defines whether the control will provide the SEQ option in addition to SYM.
HEIDENHAIN recommends using SYM because this function is suitable for all machine kinematics.
Please note that you must not simply replace SEQ with SYM, because the behavior is different depending on the machine kinematics.
Option | Meaning |
---|---|
SYM | With SYM, you select a tilting solution relative to the symmetry point of the primary rotary axis. The symmetry point lies at the center of the rotary axis. The primary rotary axis is the first rotary axis, seen from the tool, or the last rotary axis, seen from the table. |
SEQ | With SEQ, you select a tilting solution relative to the basic position of the primary rotary axis. Using SEQ only makes sense for machine kinematics where the symmetry point of the primary rotary axis lies at 0°. |
Reference point for SYM: A = –90° | Reference point for SEQ: A = 0° |
Entering SYM or SEQ is optional.
If you do not define SYM (SEQ), the control will select the solution variant with the smallest number of rotary axis movements, based on the current rotary axis positions.
If no tilting solution is available within the traverse range of the machine, the control will issue the Entered angle not permitted error message. This happens regardless of whether you have defined SYM (SEQ) or not.
Tilting solution SYM
Using the SYM function, you select a solution option relative to the symmetry point of the primary rotary axis:
- SYM+ positions the axis in the positive half-space
- SYM- positions the axis in the negative half-space
As opposed to SEQ, SYM uses the symmetry point of the primary rotary axis as the reference point. Every rotary axis has two symmetry positions, which are spaced by 180°. In some cases, only one symmetry position is within the traverse range of the machine.
Determine the symmetry point as follows:
- Perform PLANE SPATIAL with any spatial angle and SYM+
- Save the axis angle of the primary rotary axis in a Q parameter (e.g., –80)
- Repeat the PLANE SPATIAL function with SYM-
- Save the axis angle of the master axis in a Q parameter (e.g., –100)
- Calculate the average value (e.g., –90)
The average value corresponds to the symmetry point.
Tilting solution SEQ
Using the SEQ function, you select one of the solution options relative to the basic position of the primary rotary axis:
- SEQ+ positions the axis in the positive tilting area
- SEQ- positions the axis in the negative tilting area
SEQ is based on the basic position 0° of the primary rotary axis. If both solution options are within the positive or negative area, the control will use the tilting solution that requires the smallest number of rotary axis movements, relative to the current position. If you need the second-best solution, then either pre-position the rotary axes (in the area of the second solution) before tilting the working plane, or use SYM.
Examples
Limit switch | Start position | SYM = SEQ | Resulting axis position |
---|---|---|---|
None | A+0, C+0 | Not prog. | A+45, C+90 |
None | A+0, C+0 | + | A+45, C+90 |
None | A+0, C+0 | – | A–45, C–90 |
None | A+0, C–105 | Not prog. | A–45, C–90 |
None | A+0, C–105 | + | A+45, C+90 |
None | A+0, C–105 | – | A–45, C–90 |
–90 < A < +10 | A+0, C+0 | Not prog. | A–45, C–90 |
–90 < A < +10 | A+0, C+0 | + | Error message |
–90 < A < +10 | A+0, C+0 | – | A–45, C–90 |
SYM | SEQ | Resulting axis position | Kinematics view |
---|---|---|---|
+ | A–45, B+0 | ||
- | Error message | No solution in limited range | |
+ | Error message | No solution in limited range | |
- | A–45, B+0 |
The position of the symmetry point is contingent on the kinematics. If you change the kinematics (such as changing the head), then the position of the symmetry point changes as well.
Depending on the kinematics, the positive direction of rotation of SYM may not correspond to the positive direction of rotation of SEQ. Therefore, ascertain the position of the symmetry point and the direction of rotation of SYM on each machine before programming.