[Dennis] of [Made by Dennis] has been constructing a Voron 0 for enjoyable and training, and since this apparently wasn’t sufficient of a problem, determined so as to add various scratch-built enhancements and modifications alongside the way in which. In his newest video on the journey, he rigorously calibrated the printer’s movement system, together with translation distances, the perpendicularity of the axes, and the mattress’s place. The aim was to get higher than 100-micrometer precision over a 100 mm vary, and reaching this required detours into pc imaginative and prescient, clock synchronization, and linear algebra.
To appropriate for non-perpendicular or distorted axes, [Dennis] calculated a place correction matrix utilizing a digicam mounted to the toolhead and a ChArUco board on the print mattress. Picture recognition software program can simply detect the corners of the ChArUco board tiles and establish their positions, and if the digicam’s focal size is understood, some easy trigonometry provides the digicam’s place. By taking footage at many alternative factors, [Dennis] might calculate a correction matrix which maps the printhead’s reported place to its precise place.
Leveling the mattress additionally took surprisingly deep technical information; [Dennis] was utilizing a PZ probe to detect when the hotend contacted the mattress in varied locations, and had made a wiper to take away interfering plastic from the nozzle, however wasn’t glad by the mattress’s slight continued movement after making contact (this might need launched as a lot as 5 micrometers of error). To appropriate for this, he had the microcontroller within the hotend document the time of contact and ship this together with the hit sign to the Raspberry Pi controller, which retains a document of occasions and positions, letting the true contact place be seemed up. This required the hotend’s and the printer’s microcontrollers to have their clocks synchronized to inside one microsecond, which the Pi managed utilizing USB start-of-frame packets.
The ultimate consequence was already trying fairly skilled, and will solely get higher as soon as [Dennis] calibrates the extrusion settings. Should you’re searching for extra about ChArUco boards, we’ve lined them earlier than, in addition to calibration fashions. Should you’re searching for high-precision mattress leveling, you could possibly additionally try this Z sensor.
Because of [marble] for the tip!
