# Development and Preliminary Evaluation of a Lower Body Exosuit to Support Ankle Dorsiflexion
## 4 Results  
### Kinematic Data  
Mean kinematic trajectories of the ankle sagittal, transverse and frontal plane, as well as the hip and knee joint in the sagittal plane, are shown on the left side in Figures 5-9. All kinematics of the baseline measurement without the exosuit are illustrated in blue and with exosuit in red, respectively. All angles concern the left leg, on which the exosuit was worn. The gait cycle started with the heel strike and ended with the heel strike of the same leg and next stride. The stance phase, where the foot had contact with the ground, changed into swing phase at about 64% of gait cycle. The corresponding statistical test is illustrated on the right side of every figure. It indicates the SPM[t] curve (black) and the critical value (red, dashed line). By exceeding the critical value, significant differences can be observed throughout the entire gait cycle. In general, the analyzed joint kinematics within the current study did not significantly differ between the walking with and without the exosuit conditions.  
The sagittal plane motion of the ankle describes the dorsiflexion and plantarflexion degree of freedom. Positive values illustrated in Figure 5 correspond to dorsiflexion, where the foot was lifted upwards, and negative values to plantarflexion movement. At heel strike at 0% of gait cycle and the following stance phase, the angle curves of both conditions follow the same movement without any displacement. From the beginning of the initial swing phase at 64% of gait cycle, the foot was supported by the exosuit for dorsiflexion movement. At the minimum plantarflexion angle, a mean difference of \(-2.23\pm 7.01\) was noticeable.  
The ankle transverse plane motion is shown in Figure 6. The degree of freedom for adduction is depicted in the positive direction of the y-axis, and for abduction in the negative direction. The greatest difference between walking with and without the exosuit was at the minimum abduction angle during initial swing phase, of 0.72 \(\pm\) 0.89\({}^{\circ}\). Nevertheless, the slight displacements were not significantly different.  
Figure 5: (**a**) Mean sagittal ankle angle during gait cycle from heel strike to heel strike with (red) and without (blue) exosuit, and (**b**) statistical 1D SPM test; * critical t-value.  
Figure 6: (**a**) Mean transverse ankle angle during gait cycle from heel strike to heel strike with (red) and without (blue) exosuit, and (**b**) statistical 1D SPM test; * critical t-value.  
The mean trajectory of the ankle frontal plane is shown in Figure 7. Positive values indicate the inversion movement, whereas negative values present eversion movement. The maximal difference between the two conditions was 3.43 \(\pm\) 1.62\({}^{\circ}\) at 64% of gait cycle (initial swing phase). Additionally, walking with the exosuit had a slightly larger variance.  
The sagittal angle curves for knee and hip are shown in Figures 8 and 9, which summarize the flexion of the corresponding joint with positive values and an extension movement with negative values. There was no difference between walking with and without the exosuit, neither for the mean trajectory nor for the variance.