Hello, (and please bare with me as English isn't my native language)
For my business I find myself having to manage and manipulate many small light objects from my inventory. My interest would be to build myself a relatively simple system to automate most of the procedure. So I've come to seek you guys experience for input and tips on how to do this the most efficiently.
The objects being small (at most an inch long) I've thought of storing them in a vertical wall of open compartments which a small robotic device going around the surface of the wall to retrieve them.
For the device movements I've figured 2 solutions :
either have it placed on an axis which will itself will move (thus giving me the x:y access)
Or have it on a cable structure like a vertical xy plotter system (akin to this : search "Project of the ploter for my master work" on youtube as it tells me i can't link here yet)
The objects being lightweight and hard to grasp with certainty I've figured that I'd use the fact that they are magnetizable. So a small arm would come and activate then retreat and disactivate thus letting the object fall in an awaiting container under the device.
I'd probably also need a small light sensor system to verify if I'd indeed captured the object during the retrieval procedure.
All of this controlled preferably through a wifi connection to my program & its database.
I'm conscious that this is going to be a lot more complicated to effectively attain as there is bound to be many problems I've yet to discover. The programming part isn't the one I'm worrying as I've been dabbling in it for some years now
But I'd appreciate any help to point me in the right direction. Which parts would I need (as I must admit I'm a bit lost with the wide range of proposed parts on websites) ?
Is Ardino even the best choice to do such a project while trying to keep it simple enough?
Hey! I'm sorry I don't have input on your project. I just wanted to say your English is better than mine - and I only have one language. So don't feel like you need to apologize.
I will, however point out something funny you may have said inadvertently. "Bare with me" means "let's take our clothes off together". I'm sure you meant "bear with me".
I know I'm strange, but I thought it was funny. Good luck with your project.
Wouldn't some kind of vending machine mechanism be easier?
Instead of a "picker", you essentially have each container cell with it's own "pusher". And an infrared beam at the bottom just makes sure something fell through - but you might not want this anyway.
Oh how the same letters in an other order changes a meaning
I'm indeed also considering a vending machine style mechanism but only for my larger products as the smaller ones are too small and too great different number to be applicable.
Maybe a picture will be worth 1,000 words. If you could show up a picture of things that you sell and how you're managing them, we could possibly piece together a solution/plan. By the way, you can use a photo interrupter to detect if something is lifted by your electromagnet.
A wide range of products could be applicable afterward but those I have in mind right now are fishing flies as they are in a way the worst case scenario:
Can be more lightweight then that now can it.
I'll try making a sketch of the design that I'll post here later on.
Its just an intended prototype for now, so just want to see how it manages.
So here is the basic structure of it, 2 axis for X & Y with small motors (the 3 little boxes) to control the placement.
So what do I need to start out and make this ? 3 motors I suppose but which type ? how do I control them (do I need an Ardino board for each or can I just all link them to one, lets say placed on the central box) Where can I find the parts for gripping and moving along the axis.
Sorry if all of these are very amateur questions but ... that's my status for now. Just need to be pointed in the right direction.
Not really. He could use a tray.
When the system indicated low he could pull the tray and refill it.
Well, he talked about it being a wall of these things; one component (a lure) per tray/slot - that's potentially hundreds of lures, all with barbed hooks! OUCH!
;D
Though perhaps to "restock" he could have the arm/shuttle mechanism do it in reverse of the picking arrangement...
Its just an intended prototype for now, so just want to see how it manages.
You might want to look into the various projects online for homemade plotters and CNC machines; the X/Y positioning mechanism is going to be very similar (except yours is vertically oriented, vs horizontally oriented as it is for those projects). You really only need two motors, one for X travel (left-right) and one for Y (Z?) travel (up-down). However, you would need to rotate both sides of the vertical carriage at the same time (likely using lead screws - cheap threaded rod would be fine for your app - no need to get fancy and expensive with acme thread or ballscrews!). This syncrhonized movement can be handled easily with pulleys and thread, or if your system proves to be heavier than anticipated (which is possible depending on your picker mechanism), then use sprockets and toothed belt drives.
No, I can see a tray, 1inch wide, say 30 inches long, placed along a wall. Stack these 1.5 inches apart(for vertical storage-opening at top).
Or next to each other if opening at front.
Now each row is a part, each tray hold 30 parts. Its an array!
To refill, just remove the tray from the wall hangars, refill and reset.
Another way to do it would be a vertical tube. But the parts would need some sort of small container. Stack the parts in a tube, stack 20-30 tubes together. The tube has a small opening at the bottom that a arm could remove a part from. This has the advantage in that the arm only has to move in a X direction (across the bottom).
Tubes could also be mounted on a carousel that rotated. Then it just needs a simple flipper to eject a part when it comes around.
Tubes could be filled at slow times, during business simply replace a tube of parts with another tube.
Look I just found a tube source:
Hmm, maybe I should patent all this.....
(probably already done)
I think there's a tried and tested paradigm you could adopt, a CNC table. This link lumenlab.com - lumenlab Resources and Information. illustrates the mechanical structure. The X/Y axis moves across your stock tray. The Z axis lowers a magnetic picker and deposits it in an out tray.
Much of the challenge and cost of constructing a CNC machine is ensuring strength, rigidity and accuracy. You don't really need any of those for your design. Not to the degree that's required in a machine that's supposed to mill sheet metal to millimetre precision at any rate! You could map G-code to stock inventory. Run the script and off it goes. There's a massive online DIY CNC community for help.
Guaranteeing something has been picked is an interesting challenge ...
By changes in weight? Either of the entire stock area or of the deposit tray. If the weight is known for each inventory item then you'd know if something had left the table or arrived in the deposit tray or not. Would need to be very sensitive though I guess.
Light sensor, yeah I see where you're coming from but ... one per tray would be a lot of inputs so I think you'd need to detect whether something is stuck to the magnet or not once the picker head has left the table.
What about resistance? Could you measure the change in resistance (or capacitance or whatever, I'm not an engineer) across the pick up head. If it hasn't changed then it hasn't grabbed anything?
Alternatively you could not deal with it and rely on visual inspection. You would only need to count the number of items not whether they are the correct ones as in the above design picking should be reliable.
