CoM is the Center of Mass. The closer to the max value, the more stable the posture, and the closer to the min value, the more unstable the posture. 

 

To calculate the frame length, count the total number of frames in the dataset. Each frame represents a data point collected over time. The total frame length gives the duration of the motion or activity being analyzed. In this dataset, the total frame length is determined by the number of entries in the data array.