Lost keys are a real nuisance and a rather inelegant problem when keeping things locked away and safe. There are a number of companies that are looking to use technology to create easy, approachable solutions to access control. Will they catch on, or is low-tech the best option?
I look at a few different Arduino projects that can create relatively simple solutions for access control. Perhaps experimenting with Arduino will help you decide whether technology is appropriate for this problem. Check them out in Arduino Lock Devices.
By the way, feel free to get in touch if there are any other areas Arduino or otherwise you'd like me to cover. My contact info is on my bio page.
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