Mobile Phone Video Surveillance
The Concept
Take a mobile phone, build some intelligent electronics around it and presto, you have your own Remote Video Surveillance System!
This sounds quite simple however, to achieve this this project required working with several different technologies and processes!
The Creation
Initially the group obtained a few old mobile phones with built in cameras. Then the students determined the sequence of key strokes required to take the phone from a standby position, through to taking a photograph, SMS’ing it to another a mobile phone then returning the mobile phone back to its standby mode. It was interesting to note that once the receiver’s number was saved to the phone’s address book, only 3 keys were required to preform this entire routine!
The next stage was a lot of fun as it involved taking the mobile phones apart to learn how the keypad actually worked. The students discovered that they could simulate the actual keys with relays. This was ideal as they could then design an electronic circuit to switch these relays, thereby replicating keys being pressed.
The students were now ready to build the hardware circuit which would control the sequence of the relays being switched. They used a PIC microcontroller for this as it was quite cheap to purchase and relatively easy to learn how to program.
Writing the program required a lot of thinking. Several tests and improvements were needed to make the circuit match the way the phone was designed to interpret the keys being pressed.
“It was great fun taking a mobile phone apart, understanding how it works, and then making it do things we wanted it to do. We learned a lot about new technologies”
