RT Walker - Intelligent Walking Support System The goal of this research is to develop human adaptive intelligent walking support systems. In this paper, two types of intelligent walking support systems are proposed. One is an active type walking support system referred to as walking helper, and the other is passive type walking support systems referred to as RT walker. These systems are controlled so as to have variable motion characteristics according to the disabilities or the conditions of the users, so that the good maneuverability and the high safety of these systems could be realized. Citation: Yasuhisa Hirata; Oscar, C., Jr.; Asami Hara; Kazuhiro Kosuge;,"Human-adaptive motion control of active and passive type walking support system," IEEE Workshop on Advanced Robotics and its Social Impacts, 2005. pp. 139- 144, 12-15 June 2005 Links: RT Walker 2001 http://www.irs.mech.tohoku.ac.jp/rt_walker_en.html Institutional access to full text: http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=1511640&isnumber=32365&tag=1 --- Environment-adaptive Motion Control for Passive type Intelligent Walking Support System "RT Walker" We propose a concept of a new walking support system based on passive robotics for supporting elderly people, blind people, and handicapped people who have difficulties in walking, and develop a prototype walking support system referred to as RT Walker. RT Walker consists of a support frame, two casters, and two wheels with powder brakes. In this research, we control the motion of RT Walker by changing the brake torques of two wheels appropriately based on the Robot Technologies (RT). In this article, we propose the control algorithms to realize the obstacle avoidance and the gravity compensation of RT Walker based on the environment. http://sciencelinks.jp/j-east/article/200418/000020041804A0582535.php http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=1390018 --- Motion Control of Passive-type Walking Support System based on Environment Information In this paper, we propose a motion control algorithm of a passive-type walking support system based on environment information. The passive-type walking support system we developed consists of a support frame, two casters, and two wheels with servo brakes. This system has a passive dynamics with respect to the force/moment applied to it, because it does not have any actuators for driving it, so that this system is intrinsically safe for using it based on the physical interaction between the system and the human being. In this research, we control the motion of the passive walker by adjusting the brake torque of each wheel based on the environment information, so that a user could avoid the collision with obstacles, prevent missing his/her step, and compensate the gravity of the system as if the user could use it safely on any roads such as the road with steep sloop. The proposed control algorithms are applied to passive-type walker referred to as RT Walker experimentally, and we show that RT Walker can be utilized successfully in environments such as the stairs, obstacles, and slopes. http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=1570557 --- Motion Control of Passive-type Walking Support System for Avoiding Obstacles/Differences in Level In this research, we propose an environment adaptive motion control algorithm for walking support system referred to as RT Walker. RT Walker is a passive-type walking support system with only brakes and is controlled based on the information of the environment without using actuators such as motors. In this article, we propose the control algorithm for avoiding the obstacles or differences in level. The proposed control algorithm is applied to RT Walker, and we evaluate the validities of the control algorithm. http://sciencelinks.jp/j-east/article/200501/000020050104A0830362.php --- Motion Control of Variable Dynamics type Walking Support System using Brakes We propose a concept of new walking support system using brakes for supporting elderly or handicapped people who have difficulties in walking, and develop a prototype walking support system referred to as RT Walker. RT Walker consists of support frame, two omnidirectional-wheels, and two wheels with power brakes. In this research, we control brake torque of two powder brakes appropriately based on the Robot Technologies (RT) and the variable dynamics of RT Walker is realized for supporting several types of difficulty of users. RT Walker could change its dynamics without using actuators, so that the user could utilize RT Walker safely and effectively. In this article, we propose control algorithms to realize the variable dynamics of RT Walker and to navigate a user based on a path. http://sciencelinks.jp/j-east/article/200411/000020041104A0392146.php --- A new compliant motion control design of a walking-help robot based on motor current and speed measurement This paper presents a novel compliant motion controller design for an omni-directional mobile robot. In this design, an external force observer is developed based on measuring motor current and speed without using an expensive force/torque sensor. The mobile robot has a handrail to assist the elderly to walk safely and stably. In this application, adaptive motion compliance is required in accordance with the applied force of the user. Practical experimental results show that the compliance of the walking helper can be adjusted by setting dynamic coefficients of the overall dynamical system. It was demonstrated that the external force observer successfully detected the pushing as well as pulling force of a user on the handrail. The velocity of the omni-directional walking helper is adjusted according to the inferred motion intent. http://portal.acm.org/citation.cfm?id=1732782