Hi,
there is a new auto bed level sensor, that is a distance sensor with resolution 0.01mm, different from normal proximity sensor BLtouch.
more details: GitHub - markniu/Bed_Distance_sensor: Auto bed level with High resolution distance sensor
if someone interest to do that I can help to send this sensor and 3d printer main board to you for free.
Thanks!
Hi, Any updates on this? I just got this sensor and would love to help if I know where and what to change in Klipper firmware. 
Hi mark_luo,
interesting. Could you please explain, how the sensor works?
Kind regards, hcet14
I have one as well. It is an I2C device. There is Arduino test code in the GitHub. I just got it and haven’t messed around with it yet. I’m not a Klipper expert so unlikely to be the one to integrate it. Works with Marlin.
Here is the document link about how this sensor works: Data Protocol · markniu/Bed_Distance_sensor Wiki (github.com)
If anyone who like to integrate this to klipper and shared with others, please PM me or email:niujl123@sina.com, I would like to send one to you.
Hi mark_luo,
you use a TCA305. That is a very old sensor from Siemens. It is obsolete since 2021 Discontinued Products - Infineon Technologies. The datasheet is from 2005. Why did you choose this sensor?
Kind regards, hcet14
I see many inductive sensor chip in the market that clone this TCA305, and we can purchase this chip easily. Do you have any other recommended chips?
No. I didn’t know there are Chinese clones to buy. It seems, it’s a LDA355 from http://www.huaaoe.com. I was just able to find a Chinese datasheet. Couldn’t find an English one. Not sending the I2C address is a good idea. Let’s wait how HelgeKeck is doing… Kippler support · Issue #1 · markniu/Bed_Distance_sensor · GitHub
The LDA355 is dirt cheap on Aliexpress
[https://www.aliexpress.us/item/3256801354083926.html?gatewayAdapt=glo2usa4itemAdapt&_randl_shipto=US](https://LDA355 chip) Complete datasheet is on that page… In english!
hi, i found a similar version and in open source with the I2C protocol. I think this should work!
https://www.electronics-lab.com/project/inductive-proximity-sensor-using-tca505/
Thanks! I have finished integrate this BedDistance Sensor into klipper, but need to wait for merging into master branch:
https://github.com/Klipper3d/klipper/pull/6031
Am I understanding correctly that this device requires a bed surface that contains a ferromagnetic substrate, as with certain spring steel “flex” plates? In other words, am I correct that it won’t work with glass or G10, for example?
