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11 years, 1 month ago.
Wireless lock
Mbed community,
I'm a current electrical engineering student at Southern illinois university carbondale. As part of a senior design project me and a group of classmates are looking at developing a "wireless/rf/bluetooth" padlock. Or something of similar design.
The idea is to use a smartphone app (most likely android for now) to unlock the padlock. Locker-room lock, storage locker lock, etc. We are still in the brainstorming phase so we need ideas on what devices to use and how we can implement such a device.
On that note I have been browsing the mbed site and it looks like i would need an mbed controller and bluetooth or wifi addon/shields although im not sure what to do along the lines of the lock mechanism. It only needs use one communication method not both(trying to minimize size and cost) and run off of battery.
I did mention padlock but it can also be some kind of electronic locking mechanism as long as it can be used for the "storage locker" situation.
I'm fairly new when it comes to all this microcontroller stuff but any input or direction you guys can give would be great.
1 Answer
11 years, 1 month ago.
For communication, Bluetooth would be a bit simpler. You don't need a complex protocol for something like this: enter password, lock and unlock. You could also provide a "set password" feature, or you could hard-code it into your mbed. If you don't hard-code it, you'll need to use some flash storage to hold onto the password between power cycles, and a way to reset the password back to "factory default" in case the user forgets it.
For the lock, you're talking a moving mechanism, possibly a gearbox. If you use a gearbox and are somewhat serious about securely locking things, consider a "worm gear" approach, since worm gears are driven from one direction only.
Also, consider a manual override in case your battery dies.
I like your answer, ill look into the Bluetooth vs wifi options. But Im also looking as well what i should buy to get started/playing around with the different concepts.
I was looking here https://www.sparkfun.com/categories to help decide which mbed board i should use.
for bluetooth modules:
http://www.bluegiga.com/WT12_Class_2_Bluetooth_Module
https://www.sparkfun.com/products/10823
mbed options:
https://mbed.org/handbook/mbed-Microcontrollers <not quite sure but im thinking the lower power consumption battery powered once since its essentially going to be a battery powered final product