sensitivity scale factor respective to full scale setting provided in datasheet Select SDA and SCL pins for I2C communication Thank you for your help!! #include Ĭonst uint8_t MPU6050SlaveAddress = 0圆8 Here is my code block thus you can help me. I searched some useful things but I couldnt find anything about what I am exactly looking for. I can get acceleration and gyro data with a good accuracy. This is why it is necessary to have some independent indication of orientation / rotation if you want to use an accelerometer for an IMU.I am improving a project, however, I'm stucked in while trying to calculate the forward speed(velocity) from MPU-6050(The kit I use is Nodemcu). The problem becomes less important when the acceleration is very large - but for small (compared to $g$) accelerations this really won't work very well. And that means that you can't tell the difference between the two cases I drew very well - the uncertainty in $a_x$ will be very large. When the sensor is rotated and stationary, and the values are perfectly known, thenĪ_y = g\sqrt$.įor small angles of rotation, when $a_y\approx g$, that error becomes exponentially bigger - in other words, even with an accurate accelerometer it's hard to estimate $\theta$ when the angle is small. I show two situations where the $a_x$ sensor records the same acceleration, but the $a_y$ sensor records a slightly different value. For simplicity I will do this in 2D - it should be easy to see how to extend it to 3D (but that doesn't make it better-behaved). Here is the reason that your problem is not easy to solve. If that doesn't answer your question, can you please be more specific in your question about the concept you are stuck on? update But when you don't, the problem is very ill posed unless the acceleration is large compared to $g$ (or at least "not small").ĭetails of the calculation can be found in this paper. This is why it is preferable to have some independent information about the rotation of the sensor: if you have rotation sensing (not just linear acceleration measurement) you can integrate that to get the angular position this helps improve the estimate of the orientation, and then it's easier to subtract the gravity vector.įor example this answer assumes you know the rotation (orientation of the sensor) after which things are simple. The problem is that the difference between two large vectors that point almost in the same direction is a small vector with a large error on it. What you are left with is the difference vector. If you know the magnitude of $g$ accurately, you can look at the actual total acceleration observed by your accelerometer and subtract the "known" g.
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