Lukasz from Proma-Elektronika kindly sent us a unit to test, and we are quite happy with how it performs on our fiber laser machine.
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The height sensor is used to automatically set and/or maintain a fixed nozzle-to-material distance which has been determined appropriate according to the focal point of the laser beam, i.e. "autofocus".
Autofocus is enabled in the following clips, and the readout from the device shows it is maintaining the set height closely, including during/after indexing. The drilling speed was slowed down to make it easier to observe.
The C2V Laser Sense has not had issues with noise from operation or the sparks generated, which eventually became a problem with an optical height sensor used previously with this machine.
Drilling holes:
i.imgur.com/mOQMjpb.mp4
i.imgur.com/CB8KpLx.mp4
Entry holes:
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Exit holes:
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Straight cuts. Note the visible autofocusing at the very beginning:
i.imgur.com/YGVQZon.mp4
Result:
image missing https://i.imgur.com/hKo1PHA.jpeg
The testing we did is so far largely qualitative but we can say it comfortably achieves its specified 10 um (0.01mm) resolution, which is important to us. At some point it would also be good to validate the stated sampling frequency (3.65 kHz) and response time (< 2 ms).
Aside from performance, one standout feature of this unit is the information feedback right on the unit. The LED and built-in display are tremendously helpful, both during calibration, and during operation. Really a very useful feature!
Setup was quite simple and the documentation of the device function, modes, wiring diagrams, and calibration routines were helpful. A cat6a cable (shielded, twisted pairs) was perfect for making the data/power cable.
For integrating the C2V Laser Sense to our existing machine using an Aerotech A3200 controller, it was straightforward to just use the analog output from the device. It would be great to see others configure this device with LinuxCNC. Given the many modes of operation offered, it should be possible to get it set up with quite a variety of hardware.
Since precision is our priority, we went with Mode 0 which has a non-linear (exponential decay) relationship between voltage and distance.
Good grounding of the chassis was important to getting good calibration results, and luckily the calibration process is easy. Fast calibration for the reference position is just a button press. The precision calibration requires programming a small routine to get the motion speed and distance required.
The best part is the colors of the LED indicator make it easy to see when calibration should begin, when it is in progress, and most importantly, whether it has failed or completed successfully. And the built-in display even shows the calibration curve; a very nice touch!
In one instance, upon powering up the machine, the device's reading was "frozen" at a fixed voltage regardless of distance, or even touching the nozzle tip. We never figured out what the cause was. Re-initializing the system and checking the grounding did not help. But resetting the unit and recalibrating it resolved the matter. We were not able to reproduce this issue, so I guess chalk it up to machine gremlins.
It goes to show how useful the readout from the built-in display is, as that was the first and most obvious clue that something was not as expected.
Overall, very happy with the C2V Laser Sense. Thanks to Lukasz for sending us this unit. We'll be looking to purchase more units for future machines, hopefully running on LinuxCNC. If others have used this unit with LinuxCNC, please do post your results!
