Hoping you could be of needed assistance. I’m working on automated small scale roll to roll feeder - begins to unwind printed A3 wide paper roll and rewind at opposite end. The center of reels will have the cutter/die/stamp. However, during the inline process, I need the print to stop when aligned with cutter position - perhaps position/adjust paper if necessary. Having read a little bit about the Pixy, I’m assuming it could work, in this case, by detecting the printed registration mark (perhaps a black square or crosshairs) along side of paper. So my questions being, 1. How do I incorporate the camera system in order to communicate signals for stop/adjust motors etc? 2. Is there software which allows this function as well as motion controlling steppers (turning reels) for this kind of application? 3. Is there a breakoutboard or added components for BOB I could use to complete this? Important Note: I know very little about programming and electronics instead adept mechanically. The little electronic skills I have is as much as worked with steppers and drivers building my own Cnc machines and familiar with configuring Mach3 software and similar. So go easy on me thanks kindly
The Pixy can indeed detect and track an object or shape (provided the background / lighting etc is not too complex). The speed at which it tracks the object is not “super fast” and if you want to incorporate it into your setup, you’ll likely need to empirically determine the maximum feed speed. The Pixy can be programmed to send out a signal to stop / start a motor controller. It’s a more advanced sensor and there is only so much sample code out there, so more than likely you’ll base yourself off some sample code and need to modify it to your needs (for example the communication protocol to the motor controller). The other alternative is to use a vision software for PC, a decent webcam etc. However this approach requires a dedicated PC.
I plan on having a dedicated PC and As far as feedrate - not a major concern for now. My main challenge is learning how to integrate the Pixy for controlling start/stop functions and! able to automatically repeat cycles at any given number.
Are there links on here of similar applications I could review to get me on track?
I’m very interested in getting this going, so any suggestions towards taking my first step and obtaining the hardware/software, would grately be appreciated.
Do you already have a stepper motor controller? If so, you’ll need to understand the connections and communication protocol.
You can also read up about the Pixy itself (all information is online - no documentation is shipped with the product itself) and what connections and communication is possible.
You’ll need to use the Pixy to identify the specific pattern and then modify the code so it sends the right signals to your motor controller.
There are examples online (Google search), but we are not aware of any which you can use as-is.
I have the following
Nema 34 Stepper Motors x 2 (5.6A/phase)
Stepper Drivers x 2 DQ860MA (output Current 2.8A - 7.8A)
Control Board is what I’m uncertain of because I’m familiar with the following Mach3 CNC compatible boards - used them a few times in past (see links below), however it won’t suit this application. I’ve been reading about Arduino controlling steppers therefore enquiring the best suited/compatible solution. The two steppers will work the X axis motion - unwind and rewind.
The punch-cutter I plan to use an independent basic up/down action that only requires a signal that triggers after alignment succeeds. However assuming the camera system detects misalignment and requires Y axis motion, then it necessitates a third stepper - I cannot see this movement beyond -5mm / +5mm or even less.
Simplified
Paper moves/rolls East to West
Camera detects registration Mark then stops movement.
Begins alignment, perhaps X axis = west/east and Y axis = north/south or vise versa depending on position stopped.
Unfortunately we don’t sell or support those boards, so you’ll need to read up quite a bit about how to connect a microcontroller to the connector, and also what code to send it.
Another (perhaps easier) option would be with a black/white detector (no color or pattern at all). The sensor would simply report (via digital pin) if it sees black or white. This means that the side of the paper would need to be a solid color, except where you would put the mark. This would mean less programming for you. If you still want to use your stepper controller however, you’ll need to understand its interface.
Benson you explained exactly what I want - Black mark (small square or crosshair) on white paper. This will be about 10mm away from edge. The prints will be further in.
Is sensor you referring to a different product than camera solution?
The only reason I plan stepper motors because of the incremental positioniting. Initially I thought about using one DC motor operating belt drive controlling both ends - similar to conveyer however uncertain if alignment accuracy should it require reverse/fwd motion.
For black / white, you need a simple IR sensor (exactly what they use for line following robots). robotshop.com/en/infrared-light-sensors.html
If you use a small array of sensor, you can know which way to move the sheet so it’s adjusts perfectly and/or can compensate if the sheet moves left or right.
To interface this with the stepper controller, you’ll need a microcontroller (we suggest Arduino if you have not programmed before) robotshop.com/en/arduino-mic … l?limit=60
After that, it’s a question of wiring it all together and creating the code.
Please forgive my questions, I’m not very clued in sensors or Arduino controllers except CNC, gcode and mechanical, but excited to learn and test new options.
The MEGA might be a bit overkill for simple line detection (great if you plan to do other robotics projects though). You can get away with using an Uno: robotshop.com/en/arduino-uno … rev-3.html
Regarding the sensor itself, they are inexpensive enough to be able to try a few. Note that some will go “HIGH” when they see white, while others will be the opposite.
If the sensors don’t look like they include connectors or cables, you might want to get some at the same time.
If you want the Arduino to operate independently of a computer, you might want a 9V wall adapter.
The important part will be understanding the connections to your existing controller, as well as the communication protocol.
Worst case scenario - you simply buy a different stepper controller which is better documented.
Im very interested to know how you got on with this project and hope you managed to get it going.
Its something I have been working on for a long time but have been stumped.
I too am able to build the mechanical but have limited electrical experience. Thankfully I have a clever electrical mate that can help with the setup once I’ve worked out exactly whats required.
I am working on exactly the same project trying to achieve the identical result. Its unbelievable!
You’ve already asked all of my questions so am very keen to find out some answers if your open to sharing some information.
Hi, i have a printing system that use 2 different printers. So i need a Registration System that recognize Black/White Registration Marks (printed on the 1st image) to align the 2nd on top of the 1st one.
(Exactly what the Curio or Cameo or other plotter does to align the cutting path to the previous printed image).
I’m new to robots, my only guide is this forum a couple days ago.
Looks like an IR sensor and Arduino ONE its the ideal for this purpose, am i right?
What other parts/devices may i need (stepper motor or other moving sensor device, etc)?
There’s any programming about this already that i can buy and tweek to my needs?
Does any of this IR sensors will work ? IR Sensor
thanks kindly