TinyWise - TSL1401CL + ATtiny85 filament width sensor

thingiverse

This is an ATtiny85 based filament width measurement tool version. It's built upon flipper's TSL1401CL filament width measurement tool foundation. Video: iWMkjmjx1MI The LED atop the tower casts a shadow of the filament on the TSL1401CL sensor, which is comprised of a line of photodiodes. Sensor output is read by ATtiny85 MCU and processed accordingly. Analog output signal (1.75 volts = 1.75mm) can be read by newest Marlin version for filament width compensation. This adjusts extruding speed based on filament diameter variations. It's free software with a focus on simplicity in construction (no SMD tools required) and cost-effectiveness (components and PCB total €15). For build details, see instructions below: Instructions Case * Print the case (base and top) either black or color it black using a marker. I use 0.25mm layer height at 75mm/s, 40% infill, three perimeters, no support. * De-burr the 5mm LED slot, 2mm filament hole, and M3 screw guides using a drill bit. PCB * Build yourself the PCB using the provided Fritzing file or order it through the Fritzing Fab Service or OSHPark (https://oshpark.com/shared_projects/fWmrjkiq). Components: R1 = 10k ohms R2 = 1k ohms R3 and R4 = 1.4K ohms (Must be equal; any values from 1K to 10K will work) C1, C2 = 0.1uF = 100nF C3, C5, C6 = 10uF C4 = 1uF U1 = LM7805 TSL1401CL linear sensor array (http://it.rs-online.com/web/p/array-di-fotorilevatori/7857692/) ATtiny85 microcontroller (http://it.rs-online.com/web/p/microcontroller/6962327/) Note on Resistors * I use a white high-luminosity LED; therefore, I employ 10k ohms for R1. You might need to adjust it. Resistors R3 and R4 serve to pull HIGH the reset pin with a voltage divider providing 2.5 volts. They should be equal since they are used in this setup. Clicking the button will momentarily push the reset pin to 5 volts, so there is no issue when the Arduino code reads against the reset pin (roughly above 2.5 volts). Soldering Tips * Even though TSL1401CL is an SMD component, it can be easily soldered using a hand-held iron with light touch. * Use tip for lightly coating each pad and solder it with solder without touching sensor, starting one corner, followed by the other ensuring proper alignment. Programming ATtiny85 * Utilizing a spare Arduino Uno, you can utilize as ISP for programming the ATtiny85 using Arduino IDE, alternatively you could use a dedicated programmer.