Gerber viewer for your Android mobile phone

When we are working with PCB fabrication systems, "Gerber" files are widely used as the input to the fabrication device from the CAD drawing. So, It is very useful to have a Gerber viewer on your mobile phone. Recenlty, I had to work with some microstrip designs and I had to check and compare the finished product at the fabrication facility. So, I found this free Gerber viewer at "Google Play" and you can find this at here. Here are some screeshots from this application showing a microstrip patch antenna in my mobile phone.

Interfacing sensors from Android mobile phone via Bluetooth

Most of the Android powered mobile phones have many in-built sensors. Android API gives us access to these sensors in API level without low level programming. Hence, we can use Bluetooth and these sensors to get sensor data to our embedded systems (may be for your robot). I modifed the "Blutooth Chat" application sample included in Android SDK to send accelerometer data via Bluetooth from my Sony Ericsson Xperia X8.

Modifying cheap servo motor for continuous rotation

You can buy cheap servo motors from ebay for a price of less than a gear motor. But these servo motors can't be used for continuous motion. A simple modification can be done by removing the locking mechanism as in the below photos. I'm using a metal geared servo motor from ebay for this. You should also glue the potentiometer in the middle postion after cutting the lock in the gear. You can use different pulses with varying pulse width and frequency to get continuous motion in the clock wise and anti-clock wise directions.