It may be already asked question in somewhere but I am struggling!

I have a four wheel robot which I want to drive it to perform 90-degree left/right turn, I am using the **MPU6050 3dof** to get angles, however everything is ok when the DC motors are off and the readings from the **MPU6050** are pretty good. 

But when the DC motors are on, the readings start to be increase randomly. I tried to use a different power supply to the DC motors and the Arduino, but with no solution. At the end when I reset the Arduino everything was back to be normal even if the DC motors are on!

[![the bellow image is my schema](https://i.stack.imgur.com/1mbfl.jpg)](https://i.stack.imgur.com/1mbfl.jpg)
Any help will be appreciated and I am open for any suggestion.