Hi folks, newbie here trying to decide which electronics platform to learn. I have an idea for a sort of an employee timeclock in which each employee would have a USB stick that identifies him. He would insert the USB, press a button, and the device would send an HTTP REST call over the network to clock him in. All that's needed from the USB is to store at most a few dozen bytes containing the user's name and maybe an API key.
From googling, I gather that Arduinos don't really read USB drives (except the Yun). But would it be possible to use a USB for 'identity' even if not using the full capabilities of USB? Like I said, each thumb drive would only need to produce a few dozen bytes of data at most. I hesitate to use something other than a thumb drive, because it's such an easy UX, but would be open to other ideas for a way to identify the employee.
You can get Arduino shields/modules that act as a mass storage device reader (needed to read USB flash drives) but such a system is very susceptible to being abused and can create a lot of wear and tear on the USB connector.
An alternative system to consider would be RFID as it contactless there is no wear and tear and less likely to be abused. The principle of operation is the same as you have with the USB stick but the number is encoded into the RFID tag. All you need to do is match a tag number with an employee.
Thank you! I hadn't thought of the wear-and-tear problem. I'm thinking maybe a solution would be to use a 6-inch male-female USB extension cable (e.g., https://www.amazon.com/C2G-Cables-Go-52119-Extension/dp/B00CJG2ZYM) to serve as the "external" USB port on my device (which would be in some kind of box). Then if the external USB wears out from heavy use, I just replace the extender.
joeclark77:
Thank you! I hadn't thought of the wear-and-tear problem.
I still think the cheaper and more robust system would be to use RFID tags/cards. The link I posted earlier was to give you an idea how they work but if the price is wrong then ebay sell readers and tags/cards for a lot less money. You can either use cards or tags (or mix them up) depending on what suits best. Reader
10x Cards
10x Tags
olf2012:
There are inexpensive and durable solutions designed exactly for your purpose. Google iButton
Great product, thanks for the link! The main problem for me is that it's not wireless. Without giving too much away, I'm working toward a product that can be moved around within a facility and transmit data real-time over company wifi. iButton is something you carry around until you want to manually take it to a computer to transfer data.
Riva:
I still think the cheaper and more robust system would be to use RFID tags/cards. The link I posted earlier was to give you an idea how they work but if the price is wrong then ebay sell readers and tags/cards for a lot less money. You can either use cards or tags (or mix them up) depending on what suits best. Reader
10x Cards
10x Tags
I agree with you, but the thing about the RFID cards is that I think they require some special hardware and software to program (or to match with an identity in a software system). I want to create a product that's as simple and easy to set up as possible, for a company with no skilled IT staff. I figured that saving a text file on a USB stick would be hard to screw up.
joeclark77:
I agree with you, but the thing about the RFID cards is that I think they require some special hardware and software to program (or to match with an identity in a software system). I want to create a product that's as simple and easy to set up as possible, for a company with no skilled IT staff. I figured that saving a text file on a USB stick would be hard to screw up.
I will try both.
Your planned USB implementation has some obvious issues;
Easy to copy a text file onto another usb, give it to your mate "clock me in"
Wear and tear
Like others have already suggested NFC/RFID and iButtons are pretty easy.
NFC. You can buy the tags for pennies, either as cards, stickers or keyfobs. Programming can be done in advance/bulk using a simple smartphone app. (program up 100 at a time, keep them in a drawer... track issuing using spreadsheet, pen & paper.... or crayons on walls if things are that bad!). They can be copied but its a step up from USB... and there are copy protection mechanisms if you really get into it.
iButtons, price/unit is ~£3-5. Programming I havent checked in detail, I cant imagine its that bad.