Astrotracker for photography

thingiverse

Tracking gear for astrophotography. Works well with short focal lengths. Compatible with most common tripods. It was a test of FDM printer capabilities... **Note: I've reached more softness, building simplicity and small weight in this project.** Non-printable parts ------------------------ * x1 Screw DIN931 M12 90mm (30mm of screw-thread) for warm-gear. * x1 Screw DIN931 M12 80mm (30mm of screw-thread) for axis. * x1 Screw DIN931(933) M8 50mm for photohead. * x2 Thrust bearings 7201B for axis. * x2 Bearing 61901 for warm-gear screw. * x2 M12 DIN934 nut (or counternut) * x1 M8 Wing nut * 2x M3 5mm inner/stopping screws for gear wheels. * Assortment of crews DIN 7049(or 7981) 2.9mm for parts coupling. Assembly notes ---------------- * Screw of warm-gear must be polished with polishing paste. I used a piece of felt and an electrical screwdriver for it. * Parts named `prokladka_*mm.STL` used warm-gear tense adjustment. Big tense causes waving of all gear. * Big tense in axis causes spasmodic motions of camera. You should tighten the nut not too strong, but so tough avoiding lufts. Arduino firmware ------------------ ``` #include <AFMotor.h> // Connect a stepper motor with 200 steps per revolution // to motor port #2 (M3 and M4) AF_Stepper motor(200, 2); void setup() { Serial.begin(9600); // set up Serial library at 9600 bps motor.setSpeed(5); } void loop() { unsigned long last_time_point, diff; int step_period = 755; last_time_point = millis(); while(1){ diff = millis()-last_time_point; if(diff >= step_period){ motor.step(1, FORWARD, MICROSTEP); last_time_point += step_period; } } } ``` AFMotor.h is Adafruit Microstep motor library from https://github.com/adafruit/Adafruit-Motor-Shield-library