Did you calibrate the MPU6050?
great information on the sensor
There are certain things that aren’t completely specified in the datasheet. It would be better to use libraries built that are available on the internet.
where are you at with this?
How is this project going at this point, can we help, or get involved in any way?
You can also use Quadratic regulator method for controlling the bot. you will state space matrix for that. Check for self balancing bot of Carnegie Mellon University on the Internet.
I have tried it out already Madindra Aryal…Let me know if you need any help