Getting motion from a stepper motor?
I have been tasked with a small project for the day-job, we need a feed/rewind system for a foil printing machine.
Its a simple task - the device needs to take a start signal from the machine, accelerate a motor, run for a preset time, decelerate and stop.
Now, we can either go with a timed duration and adjustable speed or a fixed duration taken from the machine as a start & stop signal with adjustable speed.
The speed needs to be adjustable as the machine is variable speed and also the amount of foil to feed will vary depending on the job design.
So, my question is - how simple can we make this?
I would go straight for a Nema23, 4NM motor i think with a step/dir drive and simple PSU - these I have proven to be tough little cookies on my other machines.
But the control side - how would i look to achieve the speed ramping and velocity in the simplest way?
User input would just need to be a simple pot for the overall speed - this would set the amount of foil fed in the window provided by the start/stop signals.
Re: Getting motion from a stepper motor?
Dave You could use something like this
http://www.ebay.co.uk/itm/Stepper-mo...-/191228844298
How about a simple timer relay for the delay bit.
Re: Getting motion from a stepper motor?
A stepper with a PSU, driver and frequency generator will give you instant start at the set speed, to get ramp up and ramp down you'll need a little more complexity in your control system.
This one is crying out for a PLC, with PIC chips, Arduino etc. the world is the molusc of your choice where it comes to small control systems.
An Arduino with a few switches plus a stepper, stepper driver and PSU would give you what you need, with a little programming, you could even have a 3rd party write the software for you,
Regards,
Nick
Re: Getting motion from a stepper motor?
Thanks CliveS that looks great but with the scant info listed does not look like it does acceleration. Yes a timer relay would work here.
Magicniner - thanks thats the second suggestion for the Arduino :( trouble is i have never seen one let alone programmed or used one.
Would there be any off-the-shelf products?
PLC would be my choice but going on past experience will likely blow the budget. I will pursue this option though to find out.
Re: Getting motion from a stepper motor?
Quote:
Originally Posted by
Davek0974
Thanks CliveS that looks great but with the scant info listed does not look like it does acceleration.
Magicniner - thanks thats the second suggestion for the Arduino :( trouble is i have never seen one let alone programmed or used one.
Would there be any off-the-shelf products?
PLC would be my choice but going on past experience will likely blow the budget. I will pursue this option though to find out.
Dave,
An Arduino is to all intents and purposes a little PLC, it's worth a Google and have a look at what they can do and how easy the programming package is to learn, I've only dabbled to the morse code message from the on board LED stage,
Regards,
Nick
Re: Getting motion from a stepper motor?
If it were my task, I would go for an arduino base solution as you could have more precise control of the variables. As I have 4 Parker Digiplan drivers (integrated power supply type) I would use one to step the motor. The question was 'How simple' though and this would be another solution http://www.ebay.co.uk/itm/Adjustable...3D191228844298
Re: Getting motion from a stepper motor?
I will stick the Arduino on the list for looking at, i have been looking at those simple drivers but none have any ramp control and this will certainly need that.
Re: Getting motion from a stepper motor?
Quote:
Originally Posted by
Davek0974
I will stick the Arduino on the list for looking at, i have been looking at those simple drivers but none have any ramp control and this will certainly need that.
You might be able to use it with the speed pot connected to the arduino to ramp the speed up and down
Re: Getting motion from a stepper motor?
The Arduino is well supported at www.arduino.cc There is a library of prebuilt code for stepper motor applications. If I get the time and enthusiasm I need to get down and do a stepper controller for various jobs. John S, some time ago, indicated to me the desirability of a rotary divider with programmable angles. The application in this thread is another good idea that could be programmed in a day (if I were up to speed, which I am not at the moment). I have got a raft of other projects on the list and probably not enough lifespan left to do them (based on current list !).
Cheers,
Rob
Re: Getting motion from a stepper motor?
Thanks, looking now.
It seems what i want is not a stepper controller but a ramp pulse generator - the stepper controllers seem to want to run the motor themselves but i have a bigger drive to do that, this just needs to generate the step pulses in a trapezoidal ramp form.