Presenting: The Pyr0-Piezo Z-Sensor! A self-calibrating piezo sensor

Hi there!

I recently published a project I’ve been working on for nearly two years, with the aim of solving the biggest issue facing cheap hobbyist 3D Printers: How to get a perfect first layer on any printer, using any type of hotend, and any print surface, even swap-able ones.

While this isn’t the first Piezoelectric z-sensor that’s been brought to the 3D Printing community, it is the first to incorporate an embedded microcontroller designed specifically for self-calibrating and conditioning the signal. Right now, the alpha boards being sent out into the wild don’t have full control over this circuit, but they already seem to produce good results. The Beta and final versions should only improve upon the principles and designs being tested now.

How the piezo z-sensor works: A small piezo element (commonly a 20mm or 27mm disk like the ones used in musical pickups) is fitted to a printer in such a way that when the nozzle touches the bed it undergoes a deformation or compression. When piezoelectric elements are subjected to mechanical forces in this way, they produce a charge. In the case of the z-sensor, this little blip of voltage produced by the piezo disk gets amplified, filtered, and conditioned by the Pyr0-Piezo circuit, then picked up by the board’s embedded MCU. The MCU then sends a z-trigger signal to the 3D Printer’s controller, and viola, you’ve got a Z-sensor. Since the MCU is using an interrupt pin for this function, it causes a delay of only a few microseonds, at most.

I’ve already finished about 12 sets of alpha (rev.1.x) boards that are going out to testers, but I will be looking for beta testers within the next month. If you’re interested, I’d appreciate a ping on the discord channel!

You can find source files on GitHub, Thingiverse, and my Discord’s #resources channel:

https://github.com/pyr0ball/pyr0piezo
https://www.thingiverse.com/thing:3343928
https://www.thingiverse.com/thing:3404715
https://discord.gg/gmjgXHw