4 N-Channel MOSFET H-bridge

 

It's actually IRF1404, nice little HEXFET costing Rs. 90.

But driving it ........ very challenging !

We tried IR2110, but mosfet driver blues were taking to much time so we jumped to a shortcut we accidentally learned at NERC 2010. Using an external battery to drive the high side mosfets :D

This is what the mosfet driver gave us

A headache ! and this ....

 Total disaster :(  we can bet you can't make an oscilloscope do that :P

Tilt Measurement

Intertial Measurement Unit and the complementary filter....

Testing the IMU with voltmeter

To estimate the correct angle of the platform, we needed the complementary filter. A DKU-5 (USB to UART-TTL) cable was used to transmit the raw accelerometer and gyro values to MATLAB. Voila ! Angle estimation turned out surprisingly well (with a lot of programming feats of course).

Here's the real time MATLAB plot result

White = accelerometer, blue = gyro, green = filtered angle