We present a new kinematic calibration algorithm for redundantly actuated parallel mechanisms, and illustrate the algorithm with a case study of a planar seven-element 2-degree-of-freedom (DOF) mechanism with three actuators. To calibrate a nonredundantly actuated parallel mechanism, one can find actual kinematic parameters by means of geometrical constraint of the mechanism’s kinematic structu...

Inhalation of medication is the preferred method for treating reversible airway obstruction; however, difficulties in the use of pressurized canisters frequently lead to suboptimal results. The Aerochamber (Monoghan Medical Corp) is a portable breath-actuated device that attaches to a metered-dose inhaler (MDI) and is designed to overcome many of the problems of aerosol delivery encountered by ...

An open-loop control for underactuated mechanical systems using oscillatory inputs with amplitude and frequency modulations is investigated. Once all actuated joints are moved to their desired positions, oscillatory inputs are applied to an actuated joint to move the remaining unactuated joints. The steering force of the unactuated joints is achieved by utilizing the dynamic coupling between ac...

This paper analyzes energy dissipation mechanisms in vacuum-operated in-phase and anti-phase actuated micromachined z-axis vibratory gyroscopes. The type of actuation is experimentally identified as the key factor to energy dissipation. For in-phase devices, dissipation through the die substrate is the dominant energy loss mechanism. This damping mechanism depends strongly on the die attachment...

The direct position analysis (DPA) of a manipulator is the computation of the end-effector poses (positions and orientations) compatible with assigned values of the actuated-joint variables. Assigning the actuated-joint variables corresponds to considering the actuated joints locked, which makes the manipulator a structure. The solutions of the DPA of a manipulator one-to-one correspond to the ...

This article presents the inverse and forward pose and rate kinematics solutions for a novel 6-dof platform manipulator, actuated by two base-mounted spherical actuators. The moving platform is connected to the fixed base by two identical SPU serial chain legs. The S-joint is active, and the remaining two joints in each chain are passive. An analytical solution is presented for the inverse pose...

Over the last years evidence has accumulated that shows the possibility to analyze human brain activity on-line and translate brain states into actions such as selecting a letter from a virtual keyboard or moving a robotics device. These initial results have been obtained with either invasive approaches (requiring surgical implantation of electrodes) or synchronous protocols (where brain signal...

Currently, x-ray crystallography is the primary experimental tool employed to understand how proteins fold and assemble into well-defined structures. These diffraction methods critically depend the ability to produce high-purity crystal samples, but conventional crystallization processes are inherently slow and challenging to control. Here we explore a fundamentally different electrokinetically...

This paper presents novel micromachined two-dimensional array piezoelectrically actuated flextensional transducers that can be used to generate sound in air or water. Micromachining techniques to fabricate these devices are also presented. Individual unimorph array elements consist of a thin piezoelectric annular disk and a thin, fully clamped, circular plate. We manufacture the transducer in t...

Related Articles Three-dimensional micro electromechanical system piezoelectric ultrasound transducer Appl. Phys. Lett. 101, 253101 (2012) High energy-storage performance in Pb0.91La0.09(Ti0.65Zr0.35)O3 relaxor ferroelectric thin films J. Appl. Phys. 112, 114111 (2012) Intrinsically tunable 0.67BiFeO3-0.33BaTiO3 thin film bulk acoustic wave resonators Appl. Phys. Lett. 101, 232903 (2012) Nonlin...