Ideas

[Burnsie90]

I am a total novice with electronics. I am making a prototype of my invention and I need some advice on how to make it work. I have a small enclosure that will have a part with a gear in it. I have this wireless devise: http://www.aliexpress.com/snapshot/6483336769.html?orderId=65702578791853. What I need is when I push the button on the remote a 3.7v motor will turn my gear approximately 2 revolution, then when the button is released the motor turns the gear back the same 2 revolutions.

I was thinking of a stepper motor, but I have no idea how to control it. I have tried to look into them and was hoping to find one board that will control and drive the stepper motor.

My other issue is that all this needs to be done in my small enclosure approximately 2inches by 2inches.

Eventually, I will have a company manufacture the electronics for all this, but I need to get a prototype working.

Any thoughts and suggestions are welcome.

Thank you,
Kevin

 

[Burnsie90]

I just found these tiny stepper motors that might work. http://www.aliexpress.com/item/High...per-motor-Mini-motor-stepping/1918702041.html

 

[KMoffett]

You're going to need to know how much current your motor and receiver are going to draw to get an idea big a battery you are going to need. I would use an 8-pin PICAXE microcontroller (just my favorite for one-offs) and a stepper driver board like this: https://www.pololu.com/product/2134

Ken

 

[Burnsie90]

I ordered some parts and I am starting to figure out how this all works. I can't wait for them to get in to try it out. Thank you Ken for your suggestions. I do not know how much current the motor and receiver us. I am hoping that all this will work with a 110mah Li-on rechargeable battery.

 

[Burnsie90]

I have the parts that Ken suggested. A picaxe 08M2 and the DVR8834 driver. I also have a micro bipolar stepper motor. I have connected it all and gave some very basic code to get the motor to turn. I have it connected to a 4.8v battery on a non solder breadboard. I have the + and - rail connected to my picaxe programmer and also to VMOT and both GND's on the driver. I have M0 low, SLP high and DIR Low. I have the stepper connected the B1 and B2 and A1 -A2. I have a supper small program. My code is:

Main:
low 0 ' M0
high 1 ' SLP
low 2 ' DIR

Run:
high 4 ' step high
pause 500
low 4 ' step low
pause
goto Run

The picaxe is sending pulses to the step pin of the driver, but the driver is not sending anything out from the B and A pins (using a multimeter to check).

As stated before, I am new to all this. Can someone help me out.

Thank you,
Kevin

 

[KMoffett]

Please post a schematic of what you have with all connections and non-connections.

Ken

 

[Burnsie90]

How do I draw the schematic? Can you give me an example? Sorry, I have no electronics background.

Kevin

 

[Burnsie90]

It is setup just like the below picture. I do not have a decoupling capacitor on the motor power supply. VMOT and GRD are connected to the power bar on my breadboard (4.8v battery pack). SLEEP is connected to pin 1 of my picaxe 08M2. M0 is connected to pin 0, DIR is connected to pin 2 and STEP is connected to pin 4. My Picaxe 08M2 is mounted in my programmer board that I purchased with it.

Hope this helps.

Kevin

 

[KMoffett]

It all seem correct. I would try it with the motor.

Ken

 

[Burnsie90]

I did try it with my motor, but I didn't see any movement. Will the code that I posted earlier work or do I need to do something different to get it to move? I can move the motor with direct power, but it acts like I am not getting anything out of my driver.

Kevin

 

[KMoffett]

On simulating your program, I get errors on both "Run" and the second Pause. I think "Run" is a reserved word, so just change them to "Go". Add "500" after the second "Pause".

Ken

 

[Burnsie90]

My bad. On my program I used move instead of run and I had the 500 after pause. The program runs on my picaxe and I can see pulses (multimeter) on the step input of the DVR8834, but I cannot see any movement on the motor, nor can I see pulses from any of the A and B motor outputs. Is my concept (code) of running the DVR8834 correct?

Thank you for your help<
Kevin

 

[KMoffett]

If your wiring is as shown in the graphic it should work.

Ken

 

[Burnsie90]

Thank you Ken. It is working, I had a loose connection. The motor get pretty warm. Does that mean that I have it connected wrong? It didn't come with any specs and I can't see a difference in ohms on the legs.

Kevin

 

[KMoffett]

I would guess that your voltage might too high for it. The spec on the web page you linked to said 3-5V. It also may not have been designed to be continuously powered. If I were designing for eventual manufacture (your first post) I would look for motors that you can buy new in quantity, rather than surplus. It can affect your design choices.
Also for a "total novice with electronics" you are doing well! Keep up the good work!

Ken

 

[Burnsie90]

Thank you. This is a great learning experience. I will turn the volts down. I appreciate all your help. Now it is time to play around with it. Of course this spurred other ideas, they will have to wait.

Thanks again,
Kevin