Masaru Higuchi

Development of a power assisting system of a walking chair

In this paper, we discuss the mechanism and control strategy of power assisting systems for the walking chair and then propose a new power assisting system. A power assisting system must reflect a human operators intentions and control the assisting motors to generate required driving power. A power assisting system for the walking chair must provide a constant output velocity though human driving has variations of velocity. It must also provide a stable driving torque so that the user does not suffer any discomfort. Therefore, we proposed two types of mechanisms for power combination and compared them through experiments. Finally, we proposed a hybrid power assisting system based on the combination of two types of mechanisms, and experimentally investigated the systems effectiveness.

Development of a Walking Assist Machine Using Crutches – Motion for Ascending and Descending Steps

This paper discusses the motion of a walking assist machine using crutches when it is used to assist people with walking difficulties to ascend or descend steps. First, the basic composition of the machine, which is under development in the Mechanical Systems Design Laboratory in Tokyo Institute of Technology, is shown. Based on the features of motions for ascending and descending steps by a healthy person using crutches that were measured using a motion capture system, a parameterized velocity profile as the reference trajectory of the actuator in the machine is proposed. Values of the parameters are determined through dynamic simulation taking into consideration stability, consumed energy and user’s comfort. The effectiveness of the motion is discussed with experimental results.

Motion Generation of a Casting Manipulator With a Large Working Space

Casting manipulator has a potential to achieve far larger working space with simple mechanism by casting its gripper than the conventional types of robot. In order to enlarge the working space of the manipulator, the gripper must be cast at a high-speed. In casting the gripper at a high-speed, the motion of the manipulator must be generated which makes the best use of the actuator power while the posture of the gripper is kept stable. The present paper proposes new methods to cast the gripper at higher-speed. In proposed methods, transient swinging motion of which amplitude ranges from 90° to 180° or rotating motion of the manipulator are generated before casting the gripper by modifying the method previously proposed by Arisumi et al.. For generating a rotating motion, a new approach is also proposed that varies the length of the flexible link while generating the motion. Numerical simulations have been carried out to evaluate the methods from the criteria of the casting speed of the gripper, the required time for generating motion, and the stability of the posture of the gripper.Copyright