IEEE/ASME Transactions on Mechatronics

We have developed a standing style transfer system, or "ABLE," for a person with disabled legs. It allows travel in a standing posture even on uneven ground, a standing up motion from a chair, and allows the stairs. ABLE consists of three modules: a pair of telescopic crutches, a powered lower extremity orthosis, and a pair of mobile platforms. We present here the conceptual design of ABLE and the... View full abstract»

Proportional poppet-type cartridge valves are the key elements of the energy-saving programmable valves, which have been shown to be able to achieve good motion control performance while significantly saving energy usage in our previous studies. Unlike costly conventional four-way valves, the cartridge valve has a simple structure and is easy to manufacture, but the complicated mathematical model ... View full abstract»

The theoretical framework and the experimental validation of a new image-based position-force control for planar robots are presented in this paper. This scheme produces simultaneous convergence of the constrained visual position and the contact force between the end effector and the constraint surface. Camera, robot, and the visual jacobian parameters are considered unknown. This approach is base... View full abstract»

Using a topological model and knot theory, we propose a method for describing the condition of a rope. We also propose a recognition method based on the image information obtained from the charge-coupled device cameras to obtain the structure of the rope when manipulated by a robot. This method will help solve the difficulties of robots manipulating deformable objects by providing a theoretical fr... View full abstract»

This paper presents the torque model of a ball-joint-like three-degree-of-freedom (3-DOF) permanent magnet (PM) spherical actuator. This actuator features a ball-shaped rotor with multiple PM poles and a spherical stator with circumferential air-core coils. An analytical expression of the magnetic field of the rotor is obtained based on Laplace's equation. Based on this expression and properties o... View full abstract»

This paper presents a closed-loop optimally controlled force-sensing technology with applications in both micromanipulation and microassembly. The microforce-sensing technology in this paper is based on a cantilevered composite beam structure with embedded piezoelectric polyvinylidene fluoride (PVDF) actuating and sensing layers. In this type of sensor, the application of an external load causes d... View full abstract»

Recently, the exoskeletal power assistive equipment, which is a kind of wearable robot, has been widely developed to help human body motion. The exoskeleton for elderly people and patients, however, has some limitations due to the weight and volume of the equipment. In this paper, a tendon-driven exoskeletal power assistive device, exoskeleton for patients and the old by the Sogang University (EXP... View full abstract»

In this paper, the energetics of a flapping-wing micro air vehicle (MAV) is analyzed with the objective of designing it. The salient features of this paper are as follows: 1) designing an energy storage mechanism in the air vehicle similar to an insect thorax that stores part of the kinetic energy of the wing as elastic potential energy during a flapping cycle; 2) inclusion of simplified aerodynam... View full abstract»

This paper examines the efficacy of a novel method for anomaly detection in mechanical systems, which makes use of a hidden Markov model, derived from the time-series data of pertinent measurement(s). The core concept of the anomaly detection method is symbolic time-series analysis that is built upon the principles of Automata Theory, Information Theory, and Pattern Recognition. The performance of... View full abstract»

Binary actuation has been proposed to reduce complexity in robotic and mechatronic systems. However, a relatively large number of binary actuators are required to achieve the accuracy necessary for practical applications. Conventional actuators are not practical for such large degree-of-freedom (DoF) devices. Here, a dielectric elastomer (DE) actuator is developed for these applications. It is sho... View full abstract»

The torsional compliance of harmonic drives lends itself to torque sensing, but the elliptical wave generator in harmonic drives introduces a spatially dependent local torque ripple on the flexspline of harmonic drives. It is difficult to extract the applied torque signal from this local torque ripple if the applied torque is sensed at the flexspline of the harmonic drive. Previous methods have us... View full abstract»

This paper presents the development of an active 3-degree-of-freedom (DoF) vibration isolation system using zero-power magnetic suspension. The developed system is capable to suppress direct disturbances and isolate ground vibrations of the 3-DoF motions, associated with vertical translational and rotational modes. Two categories of control strategy for the actuators are proposed, i.e., local cont... View full abstract»

A mobile robot being used for an undergraduate course in mechatronics engineering was converted from a conventional lead acid battery to a hydrogen fuelled polymer electrolyte membrane (PEM) micro fuel cell as the power source. The application of the robot is first outlined. Next, the design of the fuel-cell-based power supply system as assembled from the commercial components is described. Finall... View full abstract»

This paper describes a direct-injection configuration of a monopropellant-powered actuator that is intended to provide high-energy-density actuation for a self-powered position- or force-controlled human-scale robot. The proposed actuator is pressurized by a pair of solenoid injection valves (each of which control the flow of a monopropellant through a catalyst pack and directly into the respectiv... View full abstract»

This paper presents an approach for stable identification of multivariable nonlinear system dynamics using a multilayer feedforward neural network. Unlike most of the previous neural network identifiers, the proposed identifier is based on a nonlinear-in-parameters neural network (NLPNN). Therefore, it is applicable to systems with higher degrees of nonlinearities. Both parallel and series-paralle... View full abstract»