Fig. 14 shows the data collected in the posture changing experiment.
The horizontal axis is time, and the vertical axis is
the extended length of linear actuators. MB-DC1–MB-DC5 denote
the extended length of the five linear actuators, as shown
in Fig. 3. At 0–25 s, the five linear actuators begin to extend
to reach the home position. MB-DC1 begins to extend at
25–55 s, and then, the upper body part is raised up. After finishing
the sitting task, the knee lifting task is performed. MB-DC4
begins to extend at 60–70 s. Then, the axis begins to extend for
rising the shank part. The whole leg of the patient is raised up
at 75–90 s. Finally, the bed is driven back to the home position.
All the linear actuators are driven to reduce their length to the
home position at 95–150 s.