IEEE/ASME Transactions on Mechatronics

This paper presents a versatile atomic-force-microscope (AFM)-based two-axis probing system for 2.5-D nanometrology. Central to this system is a two-axis compliant micromanipulator based on the AFM probe whose orientation and position can be actively changed in the scanning plane. Three enabling technologies are proposed to uniformly scan the section of the sample surface within this plane. First,... View full abstract»

This paper proposes a new bending technique with a screwdrive mechanism that allows for omnidirectional bending motion by rotating two linkages, each consisting of a right-handed screw, a universal joint, and a left-handed screw. The new screwdrive mechanism, termed double-screw-drive (DSD) mechanism, is utilized in a robotic forceps manipulator for laparoscopic surgery. A robotic forceps manipula... View full abstract»

The multicar elevator system is a revolutionary new technology for high-rise buildings, promising outstanding economic benefits, but also requiring new technology for propulsion, safety, and control. In this paper, we report on experimental results with new components for linear-motor-driven multicar elevators. We show that linear synchronous motors with optimized design and with our new safety an... View full abstract»

In this paper, we propose a framework on planning collision-free walking motion for biped humanoid robots. Our proposed planner is composed of two phases. In the first phase, the constraint condition is generated as a function of time by using the walking pattern generator. In the second phase, the collision-free walking motion is planned. To generate the collision-free motion, we add a time param... View full abstract»

This paper presents the design, implementation, and force modeling of quadrupole magnetic tweezers, which are capable of exerting magnetic forces in arbitrary 2-D directions on magnetic particles in the workspace. A lumped-parameter model based on magnetic monopole approximation is employed to describe the magnetic field generated by the quadrupole magnetic tweezers in the workspace. In this model... View full abstract»

Design complexity becomes an issue for nonlinear observers when dimension of the dynamic system is high. Exploiting the inherent structure of the dynamic system, a high-gain nonlinear observer for a class of cascade-feedback-connected systems is presented. Instead of a single observer for the entire system with high dimension, a family of observers, one corresponding to a dynamic subsystem with lo... View full abstract»

To achieve excellent contouring performance, it is no longer possible to neglect dynamic coupling phenomena that occur during contouring controls, especially for a linear-motor-driven industrial biaxial precision gantry, which often moves at high speeds. In addition, effects of significant parametric uncertainties and uncertain nonlinearities need to be addressed carefully. In this paper, a discon... View full abstract»

The feeder pipes in a pressurized heavy water reactor (PHWR) suffer from flow-assisted corrosion (FAC), which makes the wall thickness of the pipes thin. This effect is a well-known degradation mechanism of a carbon pipe with high pressure and high flow rate. Therefore, the weak parts of the pipe should be measured to guarantee the safety. This paper describes a mobile out-pipe inspection robot wi... View full abstract»

This paper presents a new methodology for the design of a robust controller to compensate for friction-induced dynamical characteristics inherently present in servodrives systems. A friction model is developed using a local modeling approach of the physical properties of friction along the operating range of the underlying system. Generally, developing a faithful model for physical nonlinearities ... View full abstract»

This paper develops a robust vision-based mobile manipulation system for wheeled mobile robots (WMRs). In particular, this paper addresses the retention of visual features in the field of view of the camera, which is an important robustness issue in visual servoing. First, the classical approach of image-based visual servoing (IBVS) for fixed-base manipulators is extended to WMRs and a control law... View full abstract»

Design and analysis of piezoelectric actuators having over 20% effective strain using an exponential strain amplification mechanism are presented in this paper. Piezoelectric ceramic material, such as lead zirconate titanate (PZT), has large stress and bandwidth, but its extremely small strain, i.e., only 0.1%, has been a major bottleneck for broad applications. This paper presents a new strain am... View full abstract»

Designing and controlling an anthropomorphic mechatronic system that is able to perform a dynamic running motion is a challenging task. One difficulty is that the fundamental principles of natural human running motions are not yet fully understood. The purpose of this paper is to show that mathematical optimization is a helpful tool to gain this insight into fast and complex motions. We present ph... View full abstract»

Recently, there has been an increasing need for development of active magnetic bearing (AMB) systems of smaller size and lower energy consumption than ever, as AMBs seek for applications in compact, portable rotating machines such as hard disk spindle and artificial heart blood pump. Among others, the three-pole AMB configuration turns out to be more profitable in terms of compactness in design an... View full abstract»

This paper describes a new motorcycle riding simulator whose purpose is twofold: 1) it can be used as a training tool for new riders in different scenarios, such as a normal traffic environments or in dangerous riding situations (avoidance, emergency braking, nearly failing or slipping situations, and bad weather conditions) and 2) it can be used to study motor cyclist behavior in such situations ... View full abstract»

This paper describes a new trajectory planning method for the output tracking control of linear flexible systems; this method computes the exact solution of the equilibrium manifold. We establish a system of differential equations by combining kinematic and dynamic constraints and reformulate them in a singularly perturbed dynamics to obtain the equilibrium manifold in the form of an infinite seri... View full abstract»