Your phone's vibration motor can turn into a microphone and give away your secrets

Your phone's vibration motor can turn into a microphone and give away your secrets
Did you ever stop and think about the vibration motor on your phone? After today, you might want to. At the Electrical and Computer Engineering school of the University of Illinois at Ubana-Champaign, Associate professor Romit Roy Choudhury and PhD candidate Nirupam Roy, have discovered that you can be spied on using the vibration motor on your phone. The vibration motor is like a speaker, and any speaker can be used like a microphone.

Choudhury and Roy wrote a paper about this. Re-arranging the applied voltage of the motor can turn the component from a speaker to a microphone. The good news is that this isn't something that can be done via remote control. Reversing the applied voltage requires someone to get into a phone and physically mess with the motor. However, it could only take a minute to set this up, soldering at "four critical junctions." 

The vibrations recorded really don't sound like they can be identified. But with voice recognition software, and algorithms that replace missing frequencies, the garbled noise can be translated into the right word an amazing 80% of the time.

Click on the sourcelink to hear an actual  pre-processed word captured by the vibration motor, the word after processing, and the word through a microphone. Choudhury and Roy will present their paper in Singapore later this month at MobiSys.

source: VibraPhone (1), (2) via TechCrunch



1. AlikMalix unregistered

Crap! Now I'm freaking out!!! /s

11. JumpinJackROMFlash

Posts: 464; Member since: Dec 10, 2014

No need to freak out, they already listen to you through the ACTUAL f**kING microphone built in to every phone!!!! No need for using this crap.

12. AlikMalix unregistered

/s = sarcasm.

2. Barney_stinson

Posts: 672; Member since: May 30, 2016


7. peace247 unregistered

because they can

10. My1cent

Posts: 370; Member since: Jan 30, 2014

McGyver could have done it better!

3. XperiaG

Posts: 178; Member since: Jun 06, 2016

Really, so to be in real danger you must give your phone to one of this tech genius so they can mess around with your device and then spy you.... yep.. an everyday jeopardy.

8. TheOldOne

Posts: 196; Member since: Mar 29, 2012

if you give your phone to this tech genius, and if his intentions are to spy on you, he will rather install a proper microphone than to adapt the vibration motor for this purpose.

4. xq10xa

Posts: 810; Member since: Dec 07, 2010

Just like that movie Eagle Eye

5. ibend

Posts: 6747; Member since: Sep 30, 2014

and soon, some evil-genius will use all connected smartphone to map the whole town using sonar, and use all camera on this planet combined with ultra fast facial recognition to find any single person he want.. (yeah, its from that movie, and that movie :-/)

6. peace247 unregistered

that movie sucked....RIP Paul.

9. Casorati

Posts: 13; Member since: Sep 05, 2014

Or you just use the microphone which is there anyways to spy...

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