Disposable diaper is heavy used in care home or hospital. It's often the case that helper doesn't notice that the patient eliminated. This is very discomfort for patient, and bad for the health. They are problem which should be solved. There are conventional incontinence sensor using gas sensor or capped electrode etc. Most of them are large size. So the patient feels something is wrong when he gets on them. It takes a lot of trouble to use because they are not disposable. These sensors are unfamiliar because of those problems. We developed device which make patient's quality of life better. We are writing to suggest that Ultra Small Disposable Defecation Sensor to solve those problem. This sensor is low cost, very small, and comfortable for patient and helper because of disposable. It enables using RFID.

Underactuated systems are those processing fewer actuators than degrees of freedom, but generally they are difficult to control. In this paper we realize the crawling motion by an underactuated robot. By changing the location of the fixed point of the robot to the environment, the constraint of the system is changed. Local accessibility of the system with changing the constraints as a nonholonomic system is shown. The control law based on partial feedback linearization is proposed and the stability of the closed-loop system is studied. We discuss the trajectory planning of the robot based on geometric relation. Experiments were carried out to demonstrate the effectiveness of the proposed controller.

Underactuated systems are those processing fewer actuators than degrees of freedom. Decrease of the number of actuators is a merit from the point of view of size and weight of the system. But generally it is difficult to control the underactuated system. In this paper we realize crawling motion by an underactuated robot. Control law based on partial feedback linearization is proposed and stability of the closed-loop system is discussed on the basis of zero dynamics. To demonstrate the effectiveness of the proposed controller experiments have been carried out.