Masatsugu Iribe

Study on a practical robotic follower to support home oxygen therapy patients-development and control of a mobile platform

Home oxygen therapy (HOT) is a medical treatment for patients suffering from severe lung diseases. Although walking outdoors is recommended for patients to maintain physical strength, patients always have to carry a portable oxygen supplier which is not sufficiently light weight for this purpose. Our ultimate goal is to develop a mobile robot to carry an oxygen tank and follow a patient in an urban outdoor environment. We have proposed a mobile robot with a tether interface to detect the relative position of the foregoing patient. In this paper, we improve mobile platform mechanisms and active wheels to maximize the step height which can be negotiated, and to allocate sufficient space in the main body to carry an actual oxygen tank. The following control algorithm is also improved and its effectiveness is demonstrated in an outdoor experiment.

A designing method of the passive dynamic walking robot via analogy with the Phase Locked Loop circuits

Recently many walking robots are developed, and almost all the researches adopt the model-based control. However the researches also adopt other ideas based on the dynamics-based control to decrease their energy consumption, to absorb the impact shock of contacting, to control the joint stiffness, etc. So it seems important and valuable for the conventional walking robot control to import the ideas based on the dynamics. On the other hand, we focus the passive dynamic walking robot which walks only by the dynamics. If the principle of the robot system is analyzed and elucidated, we can apply the essence of the system to the conventional walking robot control, and also contribute the performance gain. In this paper we propose a designing method of the passive dynamic walking robot via analogy between the Phase Locked Loop circuit and the passive walking robot system. By the proposed method, we can describe how to fix the set-up parameters and initial conditions of the passive dynamic walking robot system.

Analogy between Passive walking robot and Phase Locked Loop circuit

Recently many walking robots are developed, and almost all the researches adopt the model-based control. However the researches also adopt other ideas based on the dynamics-based control to decrease their energy consumption, to absorb the impact shock of contacting etc. So it seems important and valuable for the conventional walking robot control method to import the ideas based on the dynamics. On the other hand, we focus the passive dynamic walking robot system which walks only by the dynamics. If the principle of the passive dynamic walking robot system is analyzed and elucidated, we are able to apply the essence of the system to the conventional walking robot control, and also contribute the performance gain. In this paper we analyze the behavior of the passive walking robot system via analogy between the phase locked loop circuit and the passive walking robot system, and we ascertain that both of them bifurcate and show chaotic behavior on the same condition. Then, for the purpose of the above, we show the effectiveness of the analysis result for the passive dynamic walking robot design

Study on a practical robotic follower to support Home Oxygen Therapy patients — Prototype cart development applying the inverted pendulum control

We have proposed a practical power assist robotic cart, which we call ‘Robotic Follower’, to support daily lives of the patients undergoing Home Oxygen Therapy (HOT). And to achieve the purpose, we have developed several types of Robotic Follower. In this paper, we describe our newly developed Robotic Follower with which the inverted pendulum control technology is applied to control Robotic Follower, and then we investigate its effectiveness and prove its availability.

Prototype “RT04” that uses flexible mono-tread mobile track

It is expected that robotics is introduced into search and rescue activity, planetary explorer and investigation in extreme environment etc. The robots in such environment need high mobility against extremely rough terrain. Pressure exerted on the terrain is distributing wider, thus tracked vehicles are advantageous, accordingly. Since it is difficult for usual tracked vehicle composed of a pair of tracks to change length/width ratio a lot from 1/1 because of its turning property, serially connected tracked vehicles and paddled tracked vehicles have been introduced in order to improve the mobility. We have proposed a tracked vehicle called flexible mono-tread mobile track (FMT). The body of FMT except both side wall is completely wrapped around only by a track belt, which is possible to prevents sharp or thin edges of obstacle and cloth from penetrating. However the prototypes have rail colliding and derailing problems of the track belt caused by flexion and surface profile of the ground. The objective of the paper is, therefore, to develop a new prototype of FMT called RT04. RT04 adopts one degree of freedom rotational joint in stead of the flexible components and accurately designed guide rail system in order to prevent the belt from colliding or derailing. Rubber sponge grouser is also introduced against obstacle penetration and impact from the ground. Finally, some experimental tests validate the prototype.

SAFETY DESIGN FOR SMALL BIPED-WALKING HOME-ENTERTAINMENT ROBOT SDR-4XII

ABSTRACT In March 2003, we proposed a small biped-walking home-entertainment robot SDR-4XII (Sony Dream Robot-4XII, a prototype), which was developed for home use and entertainment. As SDR-4XII is developed for home use, it is designed to be safe. And the important roles of the safety features depend on the functions of newly developed robotic actuator “ISA-4” (Intelligent Servo Actuator 4th). The actuator contributes SDR-4XIPs motion control and safety management very much. In this paper we introduce the safety functions which are achieved in the development of SDR-4XII and ISA in detail.

Analysis and stabilization of the passive walking robot via analogy with the Phase Locked Loop circuits

Recently many walking robots are developed, and almost all the researches adopt the model-based control. However the researches also adopt other ideas based on the dynamics-based control to decrease their energy consumption or to absorb the impact shock of contacting, etc. So it seems important and valuable for the conventional walking robot control to import the ideas based on the dynamics. On the other hand, we focus the passive dynamic walking robots which walk only by the dynamics. If the principle of the robot system is analyzed and elucidated, we are able to apply the essence of the system to the conventional walking robot control, and also contribute the performance gain. In this paper we analyze the behavior of the passive dynamic walking robot system via analogy between the phase locked loop circuit and the passive walking robot system, and we ascertain that both of them bifurcate and show chaotic behavior on the same condition. Then we propose the method to stabilize the bifurcated gait

Development of a new actuator for a small biped entertainment robot which has suitable functions for humanoid robots

In November 2000, we proposed a small biped entertainment robot SDR-3X (Sony dream robot, a prototype) which realized the dynamic and elegant motion performances. Then, in March 2002, we released the development of SDR-4X which was an advanced model and had a capability of a real-time integrated adaptive motion control. And then, in March 2003, we released the latest prototype model SDR-4XII which realizes advanced motion control functions for safe in addition to its previous models. To realize the capabilities of SDR robot, there are many required performances for its actuators. In this paper, we describe the outline of the robotic actuator development and specific functions which are contributed to SDR-4XIIs control.

Development of a mobile robotic cart to support HOT patient's going out via Force and Inverted pendulum control

Home Oxygen Therapy (HOT) patients must take the conveyance cart to carry oxygen equipment when they go out. However the equipment is heavy enough to discourage the patients from going out. Therefore, in this study, we attempt to develop a mobile robotic conveyance cart to support HOT patients going out by applying Force control and Inverted pendulum control which can also prevent the falling over of the cart. In this paper, we describe the control principle of Force control with Inverted pendulum control by several dynamical simulations, and we also show the effectiveness of our proposed control system by several experiments.

Measurement System for Flexed Shape of Flexibly Articulated Mobile Track

This paper proposes and validates a system for measuring the flexed posture of the flexible mono-tread mobile track (FMT) using a flexible displacement sensor (FDS). The FMT proposed previously has a single track and vertebral structure. The flexed posture of the FMT determines its turning radius and direction; thus, knowing its posture is important. However, it is impossible to measure the shape of flexible mobile systems using sensors located internally, such as a rotary potentiometer, or located externally, such as a laser scanner. To solve the problem, we introduce the FDS to measure the flexed FMT shape. The sensor consists of two fixed electrodes, a sliding electrode, and a nylon string coated with carbon (NSCC). It works as a flexible potentiometer by moving the sliding electrode along the NSCC while maintaining electrical contact. The measurement system is implemented in a prototype of the FMT called RT02-WORMY and is validated in a series of experiments.