SmartComp™ Leads to Higher Precision in 3D Parts Processed With a Rotary Table

Precision in laser processing does not come simply from having an ultra-precise machine. Achieving tight true-position tolerances in real-world parts requires a thorough understanding of the parts, fixtures, processes and their interdependencies during fabrication. It also requires the ability to compensate for the inevitable variations in dimensions or shape of the part to be processed or in placement of the part within the machine.

LASERDYNE machines include numerous features and capabilities to address the needs for precision in laser processes. These include AFC or OFC probing to compensate for local deviations in part shape and to map 3D parts that are out of round or contain a weld seam.

These compensations ensure that the laser beam focal point is in the correct location relative to the workpiece surface for the process to produce the correct hole diameter, cut width, or weld profile.

What about part or fixture misalignment?

LASERDYNE machines also include tools to compensate for misalignments due to how parts are located in the fixture or how the fixture is placed on a rotary table (Figure 1). A part without an adjustment for these misalignments will wobble and/or precess1 as the rotary table turns.

Figure 1: A cylindrical part that is not centered on the rotary table, is tilted on the fixture mounted on a rotary table, or both is a candidate for SmartComp™.

SmartComp™

LASERDYNE SmartComp corrects the programmed position and angle of the laser beam in real-time for parts where:

The center of the part is not aligned with the center of the rotary table or
The part is tilted with respect to the center of rotation of a rotary table.

SmartComp can be used to compensate for both linear offsets and axis precession on parts processed on a rotary table, even if they are flat, round, conical, or contain curved surfaces. It is also useful for any application – cutting, drilling, and welding.

Making use of SmartComp™

To compensate for any misalignment using SmartComp, we must first know how the part is misaligned and/or offset. Manually determining the correction factors for the rotational misalignment and orientation requires knowledge of vector mathematics. Any manual process will also be time consuming and increase part processing time.

LASERDYNE SmartComp makes it easy to calculate and implement the corrections by measuring a small number of points on the part. The best way to calculate the point values is to select datum points on the part and then measure the actual position of these points using OFC, AFC or the camera.

During processing, SmartComp adjusts the coordinate system so that the programmed positions line up with the actual part position. A G20 Plane Set or $ALIGN will have the same effect when used with non-rotary based parts.

A major difference between a G20 or $ALIGN is that SmartComp maps the axis shift to the rotary table (A-axis). As the table rotates, the positions of the X, Y, and Z axes (and as an option, the C and D axes if the BeamDirector® is used) are adjusted so that the laser beam tracks the true part orientation.

SmartComp for Offset Errors

The first application for SmartComp mentioned in the introduction is for situations where the part and/or fixture is not centered on the rotary table. In other words, the centers of rotation for the rotary table are parallel but offset.

The video simulations below show two examples, one for drilling and one for welding, where SmartComp is used to provide compensation for parts that are offset from the rotary table center.

Figure 2: Video simulation of SmartComp for percussion drilling-on-the-fly of a cylindrical part whose center of rotation is offset from the center of the rotary table axis.

Figure 3: Video simulation of SmartComp for laser butt welding a flange to a cylindrical part. SmartComp is used to ensure that the laser beam follows the weld seam even though the center of rotation of the part is offset from the center of rotation of the rotary table axis

SmartComp for Offset and Tilt Errors

As mentioned above, SmartComp is also used to compensate for linear offsets that occur in combination with parts and/or fixtures that are tilted with respect to the rotary table’s axis of rotation. Since SmartComp corrects motion of linear and, as an option, BeamDirector axes, it can be used for any application.

The video simulations below show two examples where SmartComp is applied to parts that are both offset and tilted on their rotary table. The simulation on the left illustrates a percussion drilling on the fly application while the one on the right features a laser welding application.

Figure 4: Video simulation of SmartComp for percussion drilling-on-the-fly of a cylindrical part that is both offset and tilted with respect to the center of rotation of the rotary table axis.

Figure 5: Video simulation of SmartComp for laser butt welding of a flange to a cylindrical part that is both offset and tilted with respect to the center of rotation of the rotary table axis.

Still not sure?

Want to learn more about SmartComp and if it can be useful in your application?

Prima Power Laserdyne manufactures 3D laser machines for precision laser processing. We also have a team of application experts who can help you with your part processing needs.

Contact Prima Power Laserdyne Sales at 763-433-3700 or e-mail us at lds.sales@primapower.com.

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1 Precession is a change in the orientation of the rotational axis of a rotating body.