OpenPrintTag reader in s multi filament printer.
Open print tag looks like a very good solution.
Some questions I have in relation to multi filament printers such and the XL or INDX coreOne.
1. How will the RFID reader connect to the printer main board.
2, What will the reading range be
3. Will you need one RFID reader per spool holder.
4. For a multi spool holder setup where the spools are close how will the reader be able to tell which spool is in each slot - I presume rotating the tag in an out of range like on the Bambulab AMS won't be possible.
5. How often will the printer be expected to update the filament usage info - and how will print cancellations or failures handle usage info.
6. Will RFID readers/writers be able to handle multiple tags in range.
RE: OpenPrintTag reader in s multi filament printer.
- There is already and RFID reader connected to the main board since the MK4S. They just need to move it.
- Low frequency RFID is a few centimeters
- Yes
- See #3
- As often as needed, presumably on a fixed frequency
- See #3
RE: OpenPrintTag reader in s multi filament printer.
So I guess if the printers already have NFC - then the main usage is going to be moving the spool next to the printer and registering it - and then putting it on the spool holder.
Usage info would possibly be tracked by the printer and then have to be flashed back onto the spool by moving it back near the printer to de-register it before moving to a different spool.
If the solution involves multiple RFID readers in the spool holders I think the big circular antenna might mean there is a risk of two spools next to each other being close enough to the RFID reader for them both to be picked up - especially if two adjacent spools have their RFID tags on opposite sides.
RE:
You are over-thinking this. RFID readers are quite small. The "antenna" is in the device being scanned. Each device has it's own unique ID. This system is already in the Bambu AMS. The technology itself has been around for decades and all the engineering hurdles were worked out a long time ago.
RE: OpenPrintTag reader in s multi filament printer.
Wish the edit period was longer...
To answer your questions, imagine an RFID reader next to the spool holder. You mount the spool, the RFID transmitter transmits to the spool which powers the tag in the spool. The tag responds with a unique ID for the tag and information about the spool (filament type, amount remaining, etc). If another spool is placed nearby, the reader won't acknowledge the "other" spool since the first spool is still close by and registered. This would still apply to a multi-spool setup.
RE: OpenPrintTag reader in s multi filament printer.
Bambulab RFIDs don't have big antennas going right around the spool inner - they are just tiny little stickers - which are duplicated on both sides of the spools.
There is one RFID reader between each 2 filament rolls - so 3 in total.
The AMS spins the spools around to a) Move the RFIDs over the readers, and b) Move the RFIDs from the other spool not being read away from the RFID reader.
The AMS can also estimate how much filament is left by measuring how much filament move is required for each revolution of the spool - which it can detect by the RFIDs coming in and out of range.
The OpenPrintTag design of having the much bigger antenna around the whole spool means I think the RFIDs won't be easily movable out of the way by spinning the spool, won't be compatible with the AMS even if BambuLab decide to join the party, and might even interfere with Bambulab spools if they are in the same AMS as OpenPrintTag spools - but I guess maybe that is being done on purpose.
RE: OpenPrintTag reader in s multi filament printer.
My previous answer was written before you latest response - where I guess you are saying in response to my question 6 that you can have multiple RFIDs in range - and communicate with all of them individually one at a time then I think that helps with some of my concerns.
RE:
Yes, multiple readers, say in a row, can detect which spool is close to it by signal strength. Also, the size of the antenna not only affects the range but the amount of power that can be generated inside the tag from the transmitter's RF signal. Prusa slicer can estimate the amount of filament being used in a print so a simple method would be to send a m-code to the spool and simply subtract this out over time. Would definitely be cruder than the AMS solution however since things like variable spool sizes, width etc would need to be programmed into the tag.
As I was pointing out tough, all of this would have been well thought out before they release it.
RE: OpenPrintTag reader in s multi filament printer.
Of course with the AMS, variable spool sizes and such aren't supported anyway...
I wonder if it'd be possible to have a very powerful NFC reader that could eventually (once every spool has a tag) read the data on all of the spools in a small room... That would be helpful for inventory 🙂
Yes, multiple readers, say in a row, can detect which spool is close to it by signal strength. Also, the size of the antenna not only affects the range but the amount of power that can be generated inside the tag from the transmitter's RF signal. Prusa slicer can estimate the amount of filament being used in a print so a simple method would be to send a m-code to the spool and simply subtract this out over time. Would definitely be cruder than the AMS solution however since things like variable spool sizes, width etc would need to be programmed into the tag.
As I was pointing out tough, all of this would have been well thought out before they release it.
RE: OpenPrintTag reader in s multi filament printer.
OpenPrintTag does seem like a promising solution for multi-filament printers! A few points to consider:
Connection to the printer’s mainboard will likely depend on the printer’s interfacesome use USB, others might use dedicated GPIO or I²C connections.
Reading range is important, especially for setups with multiple spools close together; the system may need precise calibration to avoid misreads.
For multi-spool holders, it’s possible that one reader per spool may be required to accurately track each filament, otherwise distinguishing tags could be tricky.
Frequent updates on filament usage would help maintain accurate logs, but handling cancellations or failed prints could require additional software logic to correct usage data.
RFID readers that can handle multiple tags simultaneously exist, but performance can vary, so testing in your specific setup would be important.
Overall, it seems like a smart way to simplify filament management, especially for larger or more complex multi-material prints.
RE: OpenPrintTag reader in s multi filament printer.
I like that idea - or if it could at least use of phone app or something to move it around all of the places you store filament and just collect what your current stock is - as I find keeping track of all of the filament and knowing when to reorder quite hard to manage.
Might try out one of the phone apps shown in the video to see what sort of range if possible on an iPhone.
RE: OpenPrintTag reader in s multi filament printer.
Open print tag looks like a very good solution.
Some questions I have in relation to multi filament printers such and the XL or INDX coreOne.
2, What will the reading range be
In the video, Prusa tells that because of the large tag antenna (it's a large ring), the tag can be read, even from "the other side of a 2KG spool", a.k.a, about 20 cm?!
RE: OpenPrintTag reader in s multi filament printer.
My Additional questions to this good topic;
- Assuming we would need to upgrade all 5 spool holders to one with RFID capability (on the XL 5T), how will they communicate with the mainboard? - there are no open ports, and the GPIO Hackerboard is not available for the XL
- Will we then also get a firmware- and slicer update to communicate the filament data from the printer to the slicer, like BambuLabs do?
RE:
Open print tag looks like a very good solution.
Some questions I have in relation to multi filament printers such and the XL or INDX coreOne.
2, What will the reading range be
In the video, Prusa tells that because of the large tag antenna (it's a large ring), the tag can be read, even from "the other side of a 2KG spool", a.k.a, about 20 cm?!
Thanks yes I thought I remembered that - which sounds good in principle - but does I think also make it a bit more tricker to definitively work out which spool is in which holder.
If it can be made to work I think it will be a major step forward - because I understand its quite tricky keeping track of which filaments are in which tool on the XL - so having something like this would help.
Maybe some sort of standalone device - like a Rpi or ESP32 - with RFI'd readers(s) could then talk to the slicer via Wifi - because I guess its really the slicer that needs to know rather than the printer for most things other than usage updates.
RE: OpenPrintTag reader in s multi filament printer.
Hello,
Maybe it's a dumb question but if I have few NTAG216 It will be possible to use them or it will only work with theses specific tags ?
RE: OpenPrintTag reader in s multi filament printer.
Scanning the spool with the prusa app seems to be the cheapest and easiest solution even for older printers without NFC capability. On the core one for example its just a matter of extending the existing NFC cable and stick an antenna near the spool. Its low frequency (13,6 MHz) so a longer cable doesnt add much attenuation.
RE: OpenPrintTag reader in s multi filament printer.
Scanning the spool with the prusa app seems to be the cheapest and easiest solution even for older printers without NFC capability. On the core one for example its just a matter of extending the existing NFC cable and stick an antenna near the spool. Its low frequency (13,6 MHz) so a longer cable doesnt add much attenuation.
Agreed if the app can pass its data to the slicer automatically on a Mac or PC
RE: OpenPrintTag reader in s multi filament printer.
On the core one for example its just a matter of extending the existing NFC cable and stick an antenna near the spool. Its low frequency (13,6 MHz) so a longer cable doesnt add much attenuation.
It's surprising that Prusa did not design it that way from the start. What use of the NFC reader were they envisioning when they placed the antenna on the back of the printer? (The "transfer your WiFi credentials" seems a bit like an alibi use case. I can't imagine that they designed in the NFC reader just for this one-time use. But any more regular use would require the NFC antenna to be in a more accessible location.)
But I am wondering whether the metal side panels on the Core One are going to be a problem for an OpenPrintTag reader. The obvious location for an NFC antenna would be flat on the side panel, right next to the spool. But having the massive ground plane on the back side of the antenna it bound to mess with its properties?
RE: OpenPrintTag reader in s multi filament printer.
According to this the NFC readers in existing printers (MK4/C1) are passive - so I guess that means only designed to talk to phones rather than filament spools - so I presume a new ones are going to be required for OpenPrintTag.
RE: OpenPrintTag reader in s multi filament printer.
Hello,
Maybe it's a dumb question but if I have few NTAG216 It will be possible to use them or it will only work with theses specific tags ?
No, I tried the same and they don't work. I did have luck with ISO/IEC 15693 tags ( e.g. these: https://www.amazon.com/dp/B07GBMJNWL ) though the Prusa app threw a time out error but still wrote the tags. I tested two different filaments and they were fine. Once we understand how this all glues together, maybe they're useful, maybe not but they prove a point at least.