Fig 1.
The structure diagram of the MTP assistive device.
(A) Schematic diagram; (B) Prototype used in the experiments.
Fig 2.
A profile of the assistive cable force was used to determine the actuation onset timing.
Fig 3.
Foot segments of a musculoskeletal model.
A path actuator and cylindrical object added to the foot segments of a musculoskeletal model.
Fig 4.
Five onset times and results for musculoskeletal simulation.
(A) The five different onset times were at 12%, 18%, 24%, 30%, and 36% of the gait cycle. (B) The results of the simulations showed that the flexor hallucis longus activation was decreased the most compared to the flexor hallucis longus activation without the actuator when the onset timing was set to 30% of gait cycle. The dashed vertical line indicates toe-off event timing.
Fig 5.
Placement of the electrodes on the right ankle and MTP muscles.
Surface EMG signals from the flexor hallucis longus, extensor digitorum longus, tibialis anterior, gastrocnemius medialis, gastrocnemius lateralis, and soleus were collected during the tests.
Fig 6.
Muscle activities of six muscles over the one gait cycle.
Normalized mean EMG (left) and normalized EMG over one gait cycle (right) under actuated and non-actuated conditions are shown for each muscle. Lines link data points from same participant. Curves are averages taken over all participants; shaded regions indicate one standard deviation. The vertical lines indicate the toe-off.
Table 1.
Means, standard deviation (SD) and statistical results for normalized muscle activities during walking with the MTP assistive device under actuated and non-actuated conditions.
Fig 7.
MTP angle over one gait cycle.
Curves are averages taken over all participants; shaded regions indicate one standard deviation. The vertical lines indicate the toe-off.
Table 2.
Means, standard deviation (SD) and statistical results for spatiotemporal and kinematics parameters during walking with the MTP assistive device under actuated and non-actuated conditions.