Self balancing roboter IMU issue

Question

I build a self-balancing robot, at least that what i should have been. now i have tried implementing a complementary filter which combines gyro and accelerometer data, but the problem is that the motor and the IMU (MPU 6050) are on the same board and max. an inch away from each other.

So, if i get it right, the vibrations from the Motor do influence the accelerometer way to much, hence i am not getting any applicable result when the robot is set to the ground.

So, what techniques can i apply to get the absolute orientation?

[EDIT]

This, right now, is my code with the complementary filter. My problem is, that even when the motor is off, the yAngle value varies very much from the yAcc value, although the yAcc value is correct. Is there any error in my code causing the gyro drift to break the whole filter?

// 100.0 is dt, 14.375 the gyro-specific resolution
float gyroY = (float)(readY()) / 14.375 / (100.0);
int z = getAccZ();
int x = getAccX();
float yAcc = atan((float)z / (float) x) / PI * 180;
yAngle = 0.98 * (yAngle + gyroY) + (0.02 * yAcc);

Answer 1

What sort of values are you getting out of your accelerometer? The raw values you get from an accelerometer will not translate into any form of orientation. Here is some good reading for how to get orientation out of such a mems device.

If noise from your motors really is the issue, I would recommend implementing a Finite Impulse Response (FIR) filter. For example a moving average filter might help you out. I recommend keeping the order of the filter low however, as (depending on your Samples per Second) the higher the order, the slower the response time of the data will be. This could introduce a level of error you will have to be careful of when trying to make your robot balance.