Key fob camera modifications
Friday, May 14 2010 @ 07:10 PM BST
The key fob camera will be ideal for my project. It will provide the ability to take a picture or record video.
All I need to do is modify it so that I can control it with an Arduino. To do this I need to electronicaly press the buttons and know what state the camera is in.
I plan to do this by bypassing the buttons with opto couplers and to check the state I will use a light resistant resistor or similar device over the status led.
Having easily removed the board from the case I have soldered flying leads to the two buttons, cut the battery wires, extended them and unsoldered the small board mounted microphone and attached it again with longer leads. All a bit fiddly, but using plenty of light and a fine tipped soldering iron, I managed after a couple of tries. The leads will need attaching somehow for strain releif. I intend to mount this on some strip board. Running the leads to the strips and then soldering a male connector to the strip board. This will make it easier to mount in an enclosure and protecting my poor soldering from any mechanical stress.
This is the top of the board showing where I have carefully soldered the leads to the switches.
This is the back showing the extended battery wires(red and black on the right) and the extended mic wires on the left again black and red. The mic is marked for + on one lead and the board is marked as well so make sure you get the connections correct.
Here is the battery with extended leads but no insulation on the soldered joins yet.
Im going to be using the battery during prototyping until I have sorted out an alternative power supply.
Here is the completed prototyping board.
The camera board is mounted by a few blobs of hot glue on the usb socket and ic's. I checked they wernt even warm before I did this.
So there shouldnt be any problem with overheating or melting hot glue.
Ive added an ldr over the status led, its inder the 2 coiled red wires on the right. Attached the battery via 2 pins in case I need a battery supply while im playing with it. but also allowing me to remove the battery and supply power via the pinned connector on the right.
Here is the board plugged in to the breadboard, via a ribbon cable, ready for me to connect it to an Arduino and start playing.
The ribbon cable brings out power, earth, standby button, action button and the 2 leads from the ldr.
Connector pin outs, pin 1 at the bottom.
1 - ldr
2 - ldr
3 - standby button
4 - standby button
5 - action button
6 - action button
7 - power
8 - earth
Ive kept it simple rather than putting the opto isolators and other components on the board to make it more flexible for developing.
Once Ive got everything working how I like it Ill review how all this is connected up and decide where all the subsystems go.
I intend to etch my own pcb to hold the standalone arduino and mount the lot in a waterproof housing.
The camera will have to be mounted somehow on a board with a window and could be very similar to this with provision for mounting on standoffs.
And here it is mounted on my breadboard with optocouplers sparkfun ePir and Arduino board ready to test.
Im just getting my head arounf Fritzing and will post some nice schematics soon.