Table 2 Full feature set used for training the classification models
From: Predicting reactive stepping in response to perturbations by using a classification approach
| Feature | Description | Norm. | Mean | SD | |
|---|---|---|---|---|---|
| factor | \(\bar {x}\) | σ | |||
| xcom | Position of the CoM in x-direction (anteroposterior) | 1/hcom | 0.056 | 0.030 | |
| ẋcom | Velocity of the CoM in x-direction | 1/hcom | 0.000 | 0.057 | 1/s |
| ẍcom | Acceleration of the CoM in x-direction | 0.001 | 0.388 | m/s2 | |
| kcom | Whole body angular momentum around the CoM | \(1/(Mh_{com}^{2})\) | 0.000 | 0.012 | rad/s |
| xcop | Position of the CoP in x-direction | 1/lfoot | 0.233 | 0.161 | |
| ẋcop | Velocity of the CoP in x-direction | 1/lfoot | 0.000 | 0.578 | 1/s |
| ẍcop | Acceleration of the CoP in x-direction | 0.000 | 2.090 | m/s2 | |
| ycop | Position of the CoP in y-direction (mediolateral) | 1/wstance | 0.009 | 0.047 | |
| ẏcop | Velocity of the CoP in y-direction | 1/wstance | -0.001 | 0.185 | 1/s |
| ÿcop | Acceleration of the CoP in y-direction | -0.003 | 1.308 | m/s2 | |
| θhip | Mean joint angle of left and right hip | 0.002 | 0.075 | rad | |
| θknee | Mean joint angle of left and right knee | 0.090 | 0.085 | rad | |
| xCJC | Position of the cervical joint center in x-direction | 1/H | 0.035 | 0.028 | |
| xhip | Mean position of the left and right hip in x-direction | 1/H | 0.035 | 0.016 | |
| xknee | Mean position of the left and right knee in x-direction | 1/H | 0.029 | 0.013 |