## 3 Results
### Actuation Type 2  
In the case of Type 2, which provides torque assistance to all the lower limb joints, the target tracking results also showed a good match, and there was no significant difference according to mesh density. The generalized coordinate (Figure 7a-c), generalized speed (Figure 7d-f), and muscle activation (Figure 8a-i) showed good agreement with tracking values. The experimental EMG patterns during a natural walking speed of adults [(39; 40)] were added to (Figure 8) for comparison with the target muscle activations obtained from CMC. The EMG patterns were scaled to match the CMC results. The fiber length (Figure 9a-i) and muscle excitation (Figure 9j-r) which were not included in the objective function (Equation (1)) also showed practically the same results as the tracking values. Figure 5: Results of the fiber length and muscle excitation (Type 1). Results of the fiber length ((**a–i**), solid lines) and muscle excitation ((**j–r**), solid lines) are shown for the right limb compared to the results of CMC data (red dashed lines). The results of the fiber length are normalized by the optimal fiber length of each muscle. The difference between the mesh densities is small. See Supplementary Materials for results on the left limb (Figure S3). Figure 6: Assistive forces and torques of the external actuators (Type 1). The actuator inputs are shown for the right limb ((**a–c**), solid lines). For comparison, the GRF data are also shown for the 1 g walking (red dashed lines). Due to the periodicity constraints assigned to the actuators, the actuator inputs showed the same values at both ends. The smoother control input curves were obtained as the mesh density increased. See Supplementary Materials for results on the left limb (Figure S4). Figure 8: Tracking results of the muscle activation (Type 2). Tracking results of the muscle activation ((**(a-i)**, solid lines) are shown for the right limb compared to the objective tracking data (red dashed lines). The difference between the node densities is small. The shaded areas are surface EMG patterns obtained from natural speed walking in healthy adults from the literature [39, 40]. It is scaled to match the simulation data for comparison. See Supplementary Materials for results on the left limb (Figure S6). Figure 7: Tracking results of the generalized coordinates and generalized speeds (Type 2). Tracking results of the generalized coordinates ((**(a-c)**, solid lines) and generalized speeds ((**(d**–f)**, solid lines) are shown for the right limb compared to the objective tracking data (red dashed lines). The difference between the node densities is small, and the results closely match the objective data for all the mesh densities. Hip flexion, knee extension, and ankle dorsiflexion are positive. See Supplementary Materials for results on the left limb (Figure S5). Figure 10 shows the torque input of the Type 2 actuators. For comparison, the differences between the results of inverse dynamics in the two environments, i.e., in the absence of GRF data at 0 g (microgravity) and in the presence of GRF data at 1 g (earth), were also represented together. (ID difference in Figure 10). The knee and ankle joint actuators had similar results to 'ID difference' (Figure 10b,c). The hip actuator (red dashed line in Figure 10a) showed fluctuating results, and the deviation of maximum and minimum values was larger than that of 1 g GRF data. The maximum magnitude was about 50 Nm at 10% and 60% of the gait cycle, and the minimum was about -50 Nm at 85%. The number of design variables, iterations, CPU time, and minimum objective function value for the actuation types are shown in (Table 1). In both types of simulation, the design variables comprised  
Figure 10: Assistive torques of the external actuators (Type 2). Actuator inputs are shown for the right limb ((**a–c**), solid lines).