Is it possible to use laser distance sensor as Z probe ?

netuser

Hello!

is it possible to use laser distance sensor such as PANASONIC HG-C1050?

it have a 0-5V output, if yes we can get a bed mesh without Z motion.

Thanks !

GeneRisi

@netuser In the US, from Newark distributor , the sensor price is $488.66. If that doesn't deter you, then I think it looks interesting!

netuser

@generisi I do got one , HG-C1050 about $150.

fcwilt

@netuser said in Is it possible to use laser distance sensor as Z probe ?:

Hello!

is it possible to use laser distance sensor such as PANASONIC HG-C1050?

it have a 0-5V output, if yes we can get a bed mesh without Z motion.

Thanks !

I think that the firmware would need a mod to support that approach.

But I like the idea.

Frederick

dc42

@netuser last time I looked into this, the reproducibility of low cost time-of-flight laser distance sensors wasn't good enough for this to be viable. There are other sorts of laser distance sensor that provide better accuracy.

For that Panasonic sensor, the datasheet gives the following (sic):

Measurement center distance 50mm 1.969 in
Measuring range ±15mm 0.591 in
Repeatability 30 μm 1.181 mil
Linearity ±0.1%F.S.
Temprerature characteristics 0.03% F.S. /℃

The 30um repeatability is perhaps just about acceptable. The temperature characteristics imply that a 20C temperature change would alter the trigger height by 0.3mm, which I don't regard as acceptable.

o_lampe

@dc42 said in Is it possible to use laser distance sensor as Z probe ?:

The temperature characteristics imply that a 20C temperature change would alter the trigger height by 0.3mm, which I don't regard as acceptable.

In a heated chamber with temp sensor you'd know the environment temp and can compensate it. IIRC there is a temp compensation parameter already in Z-probe definition.

I like the idea of an analog heightmap. We wouldn't waste RAM on same_height data, but collect data only when there is a height error. That way we can produce a finer grid with the same amount of RAM. (*)

*) maybe not, because we have to store coords and height. Where a fixed grid spacing would only store height..