Solving absolute scale problem in Visual Odometry using IMU data and or distance meter

Question

the visual odometry gives me x,y,z position, unless an absolute scale. I can also have IMU data (to obtain for example roll, pith yaw information). I can also have a distance meter (to obtain a varying distance from the current object)

There is an easy way to combine these information and obtain the related scale?

Thanks!

Answer 1

If you have access to a 3D accelerometer and 3D gyroscope you can estimate (e.g. by using a Kalman filter) the biases of accelerometer + gyroscope AND estimate the scale. This paper (https://www.researchgate.net/publication/220061491_Fusion_of_IMU_and_Vision_for_Absolute_Scale_Estimation_in_Monocular_SLAM) describes two approaches how to estimate the scale given calibrated IMU data.