replacing garage door motor with stepper

My local astronomy club came to me with a problem. The retractable 10' roof had a VERY old screw style garage door opener. We have gone back and forth with contractors to repair (because the motor was very old and we can't find a replacement. Also we ruled out replacing with conventional garage doors because we would have to do way more work.


So I volunteered to mount a stepper motor to replace the other small motor. I have some experience in this style of motion control having build a CNC from scratch. However building the machine for me was the easy part, making it move was another. Mach 3 software was already out there, and to make a long story short I volunteered myself to solve the problem. I have also built an auto focuser from an arduino (again using others programming) so I have loaded an existing code into an arduino. In both instances (my CNC & Auto-focuser) computers/software control the stepper motors. I dont think anyone wants to have to donate a computer to act as a simple garage door opener.

I am almost done mounting the Nema 23 stepper (which I had) to a helical coupler, and I have an arduino board. What I need is a power supply, and a motor controller. What we ultimately want, is to press a button and the stepper spins until it hits a limit switch to indicate the door is completely closed or opened.

I was wondering if anyone would have any advice on how to accomplish this?

The main reason I want to go this route, is steppers are cheap, easily found and replaceable. All components can fit in a project box and are replaceable. I can arguably get a few arduino's and pre-program them should that particular component fail.

You need a stepper motor controller that acts on keys.

grbl_ESP32 is a grbl based controller that can execute gcode macro's when a switch is activated. You could use 2 switches to activate 2 macros. A macro is a simple gcode command line that moves the stepper to a position at a defined rate like "G91 X100 F30" move the X-axis +100 mm at 30mm/min.

Have a look at their WiKi https://github.com/bdring/Grbl_Esp32/wiki/Macro-Button-Feature

A pulse generator to send a signal to the stepper driver, limit switches, industrial door opener switch and some relays. No need for an audrino. How big of a stepper motor is needed to replace a 1/4-1/2 hp garage door motor?

A PLC can do what you want.

Even better, look for 'stepper speed controller' on Amazon or eBay. <$15 These will do exactly what you want when combined with a power supply and stepper diver.

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Originally Posted by HCE

A pulse generator to send a signal to the stepper driver, limit switches, industrial door opener switch and some relays. No need for an audrino. How big of a stepper motor is needed to replace a 1/4-1/2 hp garage door motor?

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no idea. The door isn't lifting off the ground, its sliding off a roof. Its an observatory roof cover. I figure since my CNC motor can lift my tormach head vertical with no problems, it can slide a screw driven garage door along some rails.

Hi Nate- since your into Arduino try this... I suggest you put a torque wrench on the drive screw and estimate the torque required before you commit to the stepper system. Then you will know what torque you need to move the thing Peter

https://www.arduino.cc/en/Tutorial/L...erSpeedControl