How would you design/make this?  (display image based on item and proximity) - Page 1
Forum section: electronics / projects

author: Corporate666
author_rank: Unknown
timestamp: May 18, 2020, 02:11:07 am
content: I'm curious how others would go about this one. I have a CNC machine which contains 20 pallets, each of which can load into the machine. Each pallet could have one or more parts on it and each part/pallet has different fixturing... some of them the operator just needs to install bolts or fasten a clamp, others they need to line up something a certain way, etc.I want to put a touch screen next to the loading area that will identify the current pallet in the loading area and what side the pallet is facing forward (towards the operator) - then based on that it will display a screen showing what the operator should do.My first thought is RFID tags on each of the 4 sides of each pallet and a medium range reader locating in the loading area. Then feed that data into a Raspberry Pi, and have a web application written in CherryPy that will read the data from the RFID scanner and display a web page. That also allows me to do things like have the operator acknowledge they have loaded the parts correctly, etc.Does anyone have any feedback/criticism or better ways to do it? I am thinking of RFID because the pallets could be covered in chips/coolant during machining, so any sort of optical reader would be problematic. I also have no power on the pallets, and don't want to mess with batteries. On the computer side, a web page seems the simplest way and saves me having to dick with I/O lines directly in/out of the machine and allows the aforementioned functionality through a touchscreen.If others agree with RFID, would anyone suggest a specific reader for this?

author: dmendesf
author_rank: Frequent Contributor
timestamp: May 18, 2020, 03:53:29 am
content: Maybe this one:https://www.sparkfun.com/products/14066

author: coppercone2
author_rank: Super Contributor
timestamp: May 18, 2020, 04:42:27 am
content: dude your not doing your name justice, hire engineer for 12$ an hour to blow it with compressed air and prod a fucked up mechanism with a broom that you promised to replace 12 yearly meetings agodo your part for the unemployment crisis

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 18, 2020, 04:52:11 am
content: Sure, NFC tags or whatever are one way.Barcodes and a scanner, don't need any programming, just print out the tags. Simpler?The traditional industrial version of what you describe, I think would run everything through a PLC; I've seen things like this were there's a touch screen with widgets controlled by the PLC, and, something stuff happens, there's your tag and whatever.Lower level would a microcontroller doing everything, but that'll take a lot more development than using the rPi; and if you suddenly need network or database access, good luck with that!Easier would probably be a PC and some scripts; the tags might read out via COM port, and that can basically be ran through some basic scripts (maybe not batch files, but pretty much any proper scripting language will do).Doing exactly that, on a rPi (a PC on a board, after all), would definitely do.Overkill? Sometimes not.Tim

author: Corporate666
author_rank: Unknown
timestamp: May 19, 2020, 01:31:26 am
content: Thinking about it more - I'm going to go with barcodes and a continuous scanner. NFC would be problematic with enough radio power to read off metal surfaces at the required distance, and metal slivers would be problematic for either - so I'll need to solve that anyway.I can think of a few ways to automatically load a web page based on a new barcode being scanned but I'm not totally happy with any of the solutions I've come up with. Any better ideas? Basically whenever a new barcode is scanned, I would like a browser window to refresh with a new page detailing instructions for that specific part/fixture.