Need Help!- Need a circuit to control a single stepper

[wwendorf]

Hi All,

I'm hoping someone here can help me with a project I am working on. Unfortunately, I don't have any electronic design knowledge. I know how to put together circuits, but I don't understand how to create them. I also have no experience or equipment to program an EPROM or PIC.

Here is what I need to be able to do.

The high level goal is to be able to control a single stepper motor with a single circuit that is NOT connected to a computer.

On a lower level, these are the functions that are absolutely necessary.
- Speed control (1 rpm to 10 rpms)
- Capability to flip a switch and run the motor in reverse
- On/Off switch to Power entire circuit
- Hold switch to pause the motor but lock it in position by leaving the power to the circuit on (possibly for long periods of time)
- High torque output on the motor
- Ability to run for hours at a time without overheating or burning anything out

These are my "wish list" of functions:
- The ability to step a certain number of degrees at a time (no fraction of degrees)
- A switch to control a relay that controls a 110V outlet.
- Some method similar to a light dimmer to control the voltage going out to the 110V circuit. This 110V circuit drives a small 8000 rpm motor.

If anyone could either direct me to a circuit that would do most/some of this, or would be willing to help me, I would appreciate it. I would like to avoid having two separate circuit board, and would prefer that it be one board (if this is possible) as I want to put the circut, switches and POTs into as small a project box as I can.

Thanks in advance!

Wade

[JonLed]

What kind of a load do you plan on the stepper moving? Also what is the 120V going to operate?

Jon

[wwendorf]

It is slowly rotating the spindle of a type of ornamental lathe that I built. There is not a lot of force as I am only taking about 50/1000th cuts with the cutter at a time out of wood. The 120V is going to be operating what is called a horizontal cutting frame, but basically is an 8000 rpm motor.

Oh, that's the other thing that I forgot to mention, I need the ability to vary the 120V circuit with something like a light dimmer to allow me to slow down the motor attached to it. I currently do this with a light dimmer that I put in a junction box and it works great. I edited the main post to include this last item as well.

Wade

[JonLed]

Originally Posted by wwendorf Hi All, I'm hoping someone here can help me with a project I am working on. Unfortunately, I don't have any electronic design knowledge. I know how to put together circuits, but I don't understand how to create them. I also have no experience or equipment to program an EPROM or PIC.

Do you have a computer with a serial port?

Here is what I need to be able to do. The high level goal is to be able to control a single stepper motor with a single circuit that is NOT connected to a computer. On a lower level, these are the functions that are absolutely necessary. - Speed control (1 rpm to 10 rpms) - Capability to flip a switch and run the motor in reverse - On/Off switch to Power entire circuit - Hold switch to pause the motor but lock it in position by leaving the power to the circuit on (possibly for long periods of time) - High torque output on the motor - Ability to run for hours at a time without overheating or burning anything out These are my "wish list" of functions: - The ability to step a certain number of degrees at a time (no fraction of degrees)

fixed or variable degrees, if variable how do you want to control it

- A switch to control a relay that controls a 110V outlet. - Some method similar to a light dimmer to control the voltage going out to the 110V circuit. This 110V circuit drives a small 8000 rpm motor.

hp?

If anyone could either direct me to a circuit that would do most/some of this, or would be willing to help me, I would appreciate it. I would like to avoid having two separate circuit board, and would prefer that it be one board (if this is possible) as I want to put the circut, switches and POTs into as small a project box as I can. Thanks in advance! Wade

Any pictures of it?

Jon

[JonLed]

Here's a simple circuit that could be used to control the motor, depending on the size, about 1200 Watt limit.

Jon

[orbyog]

http://www.allmotion.com/products_grid.htm

[wwendorf]

Wow, this circuit board looks like it might be a start for me.

http://www.allmotion.com/IntelliINCHDescription.htm

I will have to check into one of these. It looks like it might have what I need except for the ability to move a certain # of degrees.

JonLed:
1) Yes, I have a computer with serial port, but no programmer. I have a friend who has some pic programmers tho.
2) I need to be able to move it any number of degrees in increments of at least 1 degree. I was thinking along the lines of "push a button X number of times, where X is number of degrees (let's say 10 degrees), then the pushing another button would move it the number of degrees that was entered in via the button (10 degrees)
3) Here is the info on the motor I use for the cutter: http://www.grainger.com/Grainger/items/2M037 (1/12 HP) or http://www.grainger.com/Grainger/items/2M033 (1/15 HP)
4) I don't have a pic available right now, but can take some a post some in a few days.

Wade

[JonLed]

Originally Posted by wwendorf Wow, this circuit board looks like it might be a start for me. http://www.allmotion.com/IntelliINCHDescription.htm I will have to check into one of these. It looks like it might have what I need except for the ability to move a certain # of degrees. JonLed: 1) Yes, I have a computer with serial port, but no programmer. I have a friend who has some pic programmers tho. 2) I need to be able to move it any number of degrees in increments of at least 1 degree. I was thinking along the lines of "push a button X number of times, where X is number of degrees (let's say 10 degrees), then the pushing another button would move it the number of degrees that was entered in via the button (10 degrees) 3) Here is the info on the motor I use for the cutter: http://www.grainger.com/Grainger/items/2M037 (1/12 HP) or http://www.grainger.com/Grainger/items/2M033 (1/15 HP) 4) I don't have a pic available right now, but can take some a post some in a few days. Wade

So it sounds like you're going to need some sort of display to show how many degrees you're setting it to move.

http://www.allmotion.com/EZInchdescription.htm looks like it might work.
You'll have to have some gear reduction, if you want to be able to move exactly in 1 degree increments, since most step motors are 1.8 degree/step.

I don't do pigs, but if you want to use some sort of 8051, I can help you. There are controllers that you don't need a programmer for, just a serial port.

Jon

[wwendorf]

I don't know if I really need a display. I was thinking along the line of something like this:

1) Operator decides they want to move in 9 degreee increments.
2) Operator then positions his start point using forward and reverse.
3) Operator sets the direction to move.
4) Operator presses the "1 degree" button 9 times, then performs his cut.
5) Operator presses the "advance X degrees" button which automatically moves 9 more degrees, and performs his cut.
6) Repeats steps step 5 until he has completed his cuts.

Press of the "1 degree" button resets the counter that defines the number of degrees needed to move.

I don't know if this feasible, just seems pretty simple solution. Maybe a display would be easier, I don't know.

Also, I have been using a 3:1 gear reduction, actually a timing belt and pulleys, to give me more power from a small motor. I guess I'd like 1 step to be about 1/4th of a degree for better resolution. Thanks for the info on the # of degrees of a step. I forgot about that.

Wade

[wwendorf]

In addition, i'm going to order the IntelliInch as it will let me test a stepper motor in my machine to make sure it has enough power. That will at least get me started with a proof of concept that my idea will work on this machine.

Wade

[JonLed]

Originally Posted by wwendorf In addition, i'm going to order the IntelliInch as it will let me test a stepper motor in my machine to make sure it has enough power. That will at least get me started with a proof of concept that my idea will work on this machine. Wade

What is your inclination towards the http://www.allmotion.com/IntelliINCHDescription.htm over the http://www.allmotion.com/EZInchdescription.htm drive? Your decision, just curious.

Jon

[wwendorf]

IntelliInch
· 4 Function input GO LEFT, GO RIGHT, LEFT LIMIT , RIGHT LIMIT
· 1 Amp Chopper (PWM) Stepper Driver.
· MilliOhm FETs allow board to run cool at 100% current
· Operates from 9V to 30V
· 1" X 1" X 0.5" Thick
· 1/16th microstep resolution for smooth motion
· Move current and speed settable with Potentiometers
· Auto reduction to 1/3rd move current in hold mode
· Fully ramped smooth accelerations and speeds
· Acceleration settable by fixed resistor
· Hold current automatically selected upon move completion.
· Accepts TTL Level Inputs.

EZ Inch
4 Wire input STEP,DIRECTION,GROUND,POWER
· 1 Amp Chopper (PWM) Stepper Driver.
· MilliOhm FETs allow board to run cool at 100% current.
· Operates from 12V to 30V.
· 1" X 1" X 0.5" Thick
· Eighth,Quarter,Half, or Full Step - Dip Switch Selectable.
. 1/16th microstep resolution special option available.
· Hold and Move current settable with Potentiometers.
· Move current automatically selected when step input is active.
· Hold current automatically selected upon move completion.
· Accepts 24V or TTL Level Inputs.
. Upto 25000 pulses per second.

I guess between the 2, the EZ Inch requires pulses, whereas the IntelliInch appears to just be switch inputs.

With the EZ Inch I would have to have another circuit to send the pulses. The EZ Inch appears to be the way to go once I could get someones help in designing a program in a chip to handle various inputs and do the degrees stepping I mentioned, but the IntelliInch I could likely have operating in an afternoon by just wiring up some switches.

I could be wrong (and please correct me if I am) but that is what I see from reading the 2 descriptions.

Wade