The CAD design of the main bed is shown in Fig. 1(c). The
specification of the bed chassis is 2200 mm × 846 mm. Four
wheels are installed under the bed chassis frame for the moving
task. The size of the bed is 2200mm×910 mm, and the height is
450 mm. The length of the upper body part is 800 mm, the
bottom part is 350 mm, the thigh part is 400 mm, and the shank
part is 650 mm. A 300-mm stroke linear actuator is connected
to the upper body part, the other two 250-mm-stroke linear
actuators are connected to the bottom part, and the rest of two
200-mm stroke linear actuators are connected to the shank part.
Totally, there are five linear actuators used tomove the bedplates
over the bed chassis frame and make the bed topple and fall.