case_images: PMC5891644_01
case_images: Illustration for level 1 training protocol: plate cleaning task.
case_images: fnhum-12-00125-g0003.jpg
case_images: PMC5891644_01_fnhum-12-00125-g0003.jpg
case_images: F3
case_images: Level 1 task, plate-cleaning task: the participant was requested to wear the orthosis and hold the plate in a horizontal position close to the trunk with the non-paretic arm (as shown in Figure 3A). If the participant successfully passed the BF control check, the orthosis would assist the participant to perform elbow extension (as shown in Figure 3B). After extending the participant's elbow, the device would ask the participant to flex his elbow to complete the task cycle (as shown in Figure 3C).
case_images: Illustration for level 2 training protocol: lifting and placing task.
case_images: fnhum-12-00125-g0004.jpg
case_images: PMC5891644_01_fnhum-12-00125-g0004.jpg
case_images: F4
case_images: Level 2 involved lifting a bucket: the participant was requested to wear the orthosis, extend both of his arms and hold a bucket (as shown in Figure 4A). If the participant successfully passed the BF control check, the orthosis would assist the participant to perform elbow flexion to lift the bucket (as shown in Figure 4B). After flexing the participant's elbow, the device would ask the participant to extend his elbow to put the bucket on the desk (as shown in figure 4C).
case_images: Illustration for level 3 training protocol: picking-up and placing task.
case_images: fnhum-12-00125-g0005.jpg
case_images: PMC5891644_01_fnhum-12-00125-g0005.jpg
case_images: F5
case_images: This was defined as the initial position (as shown in Figure 5A). The device would wait for 3 s, and the FES unit would be switched off so that the participant could hold the object (as shown in Figure 5B). After grasping the object, the device would give vocal instruction to ask the participant to flex his elbow to pick up the ball from the desk (as shown in Figure 5C). After the orthosis reached the designated extension angle, the FES unit switched on, so that the participant could release the object in his hand (as shown in Figure 5D). BF control checking was also used in this phase (as shown in Figure 5E).