According to Japanese elderly society and lower birth rates, a healthcare support device that can provide pas sive exercise to a patient at home or hospital without any caregivers has been desired. In the previous study, a Tetrahedral-Shaped Soft Pneumatic Actuator (it is called “TSA” for short) using three Extension type Flexible Pneumatic Actuators (it is called “EFPAs” for short) was proposed and tested as a healthcare support device for wrist. Also, K. Hase developed the six-legged mobile robot that consists of six TSAs. The robot can be available to use a core training and amusement machines based on video game for patients or elderly. The previous mobile robot consists of six TSAs. The control system that consists of the previous robot and 18 on/off valves was also reported. The sequential driving pattern for moving forward and rotating in clock-wise and counter clock-wise was investigated. As a result, it could be confirmed that the previous robot could move toward six horizontal directions and rotate toward both clock-wise and counter clockwise. However, the previous six-legged mobile robot lacks the load capacity to carry the patient on board. Therefore, in order to increase the carrying load per plane unit area of the robot, a miniaturized TSA which was increased maximum generated force of 20 N compared to the previous one was developed. In this study, an 18-legged mobile robot that consists of 18 miniaturized TSAs was proposed and tested. As a result, it can be confirmed that the improved robot can translate and rotate by changing driving pattern of each EFPA as same as the previous robot. By increasing the number of legs per plane unit to get enough carrying force of human, the estimated lifting force of the 18-legged robot is improved to 2700 N, that is 3.2 times compared with the previous one. Also, it can be confirmed that the robot is capable of translational and rotational motion even under a load of 392 N. In addition, in order to develop an actuator that can give translational force, inclined angle and vibration to the seat without mobility, a parallel link-type soft actuator that consist of six EFPAs and six coil springs was proposed and tested. The driving test was carried out. As a result, it can be confirmed that the upper plate of the tested actuator can move horizontally toward six radial directions every 60 degrees and bend toward six radial directions every 60 degrees by changing pressurized EFPAs.
