Blind Motor NEMA 17

thingiverse

I'll upload more details as soon as possible, but the idea followed having tried the original design, only to have the weight of my blind (3m long, 2m drop) break the gearbox on the suggested steppers. The item screws to the wall via the hole inside the bearing mount and uses a standard 608 bearing. I used a motor - 17HS13-0404S. The screw through the worm wheel is a M4 x 50mm countersunk cap socket allen screw and M4 nylock. The cover is held on by M3 x 10mm screws. Motor is interference fit but holes are there if you want to secure with screws. The blind tube is suitable for ID 24mm. I didn't need a second hole to secure the unit to the wall, but one can just be drilled if needed. I set up the code today to work with the L298n bridge. This isn't the most efficient way of driving the motor, as it uses the stepper.h library. Better integration would be to set up with the AccelStepper.h library and use a proper stepper driver giving you the ability to use accelerate etc. However, link to the code is here - https://github.com/skylineboy20000/Roller-Blind-Nema17 Credit for the majority of this work goes to niday and I have only modified the code to work with a L298N H bridge to drive a NEMA 17 motor. In addition, buttons are included to control UP/DOWN and Reset. MQTT and WebSockets are still integrated. "L298N Set-up Stepper color connections vary by stepper motor, best to look up which wires go to which coil and then connect as appropriate to Out 2 to 4. Jumpers are set to drive a Unipolar stepper and jumper in place to drop the 12v input down to a 5v pin to power the Node MCU. L298N > Node MCU Int 1 - D1 Int 2 - D3 Int 3 - D2 Int 4 - D4 12V Power into L289n GND 5V out > Vin on Node MCU GND > GND on Node MCU (Important these share a common ground) D5 - Switch to Ground D6 - Switch to Ground D7 - Switch to Ground There are two parameters to pay attention to in the code that may be adjusted as needed. StepsPerRevolution - Currently set at 200 which is standard for most steppers (1.8 Degree) small_stepper.setSpeed(150); - Set's the RPM of the stepper, this you'll need to set specific to your motor based on the size of the blind and voltage you're supplying. I'll get some pics up as soon as possible, and I've uploaded the design files if anyone wants to modify.