A big update. I have completed the PCB layout, generated the BOM and have an initial idea of total cost of components. But first, here is what the board will look like.
The big square border around the camera module is a place holder for additional lens. The camera comes with fixed focus length of 30cm. The thought is to add external lens and play with viewing angle and focal length. The two LED's on top and bottom of camera are for illumination. They are high power LED's. Now your robot can see in the dark.
Here is updated schematics, with layout and BOM. Sparkfun forum does not allow me attach pdf file, so get it from link below.https://docs.google.com/file/d/0B9g-44wqIYIHODc3eXhUN2liLWM/edit
The total cost of components is coming up to be $37. This does not include shipping & handling charges by Digikey, PCB vendor, etc. The most expensive items are
1) PCB board: $12.53 (This price is per unit when you build 10 boards)
2) STM32 processor: $10.99
3) Camera Module $6.54
I am planning to build 10 boards in the initial build, out of which 5 are spoken for. The other 5 are up for grabs at $40 a piece. Basically it is cost of components. I am assembling the boards at home so assembly charges are zero.
I am placing the order for PCB and components on Monday, July 15th. We should have PCB fabricated and ready for assembly by Aug 1st. Hopefully we will have a working board by 2nd week of August.
There is still a day for last minute additions and updates. If you have a suggestion please share.