On dynamic mass capture by flexible robots

Abstract In this paper we investigate the dynamics of the process when a robot intercepts and captures a moving object. This operation is called dynamic mass capture. The effects of structural flexibility of the robot is taken into consideration. In terms of time the analysis is divided into three phases: before interception (finite motion), at the vicinity of interception and capture (impulsive motion), and after interception (finite motion). Special attention is paid to the modeling of the second phase when the robot intercepts and captures a target and it becomes part of the end effector, thus, the system’s degrees of freedom and topology suddenly change. To describe this event, an alternative approach is proposed. This is based on the use of a class of impulsive constraints, the so-called inert constraints. Jourdain’s principle is employed to derive the dynamic equations for both finite and impulsive motions. Based on the proposed approach, simulation results are presented for a flexible slewing link capturing a moving target. These results are compared with the observations of an experiment. Good agreement is found between the experimental and simulation results, which suggests that the analysis presented in this paper can be used with confidence in investigations of robots intercepting and capturing moving objects.

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Applying label-free dynamic mass redistribution technology to frame signaling of G protein–coupled receptors noninvasively in living cells

Nature Protocols ◽

10.1038/nprot.2011.386 ◽

2011 ◽

Vol 6 (11) ◽

pp. 1748-1760 ◽

Cited By ~ 111

Author(s):

Ralf Schröder ◽

Johannes Schmidt ◽

Stefanie Blättermann ◽

Lucas Peters ◽

Nicole Janssen ◽

...

Keyword(s):

G Protein ◽

Living Cells ◽

G Protein Coupled Receptors ◽

Label Free ◽

Dynamic Mass ◽

Mass Redistribution ◽

G Protein Coupled ◽

Free Dynamic

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Combined Magnetohydrodynamic and Geometric Optimization of a Hypersonic Inlet

International Journal of Aerospace Engineering ◽

10.1155/2009/793647 ◽

2009 ◽

Vol 2009 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Kamesh Subbarao ◽

Jennifer D. Goss

Keyword(s):

Magnetic Field ◽

Numerical Optimization ◽

Splitting Method ◽

Optimization Procedure ◽

Geometric Optimization ◽

Control Parameters ◽

Flow Solution ◽

Hypersonic Inlet ◽

Mass Capture ◽

The Magnetic Field

This paper considers the numerical optimization of a double ramp scramjet inlet using magnetohydrodynamic (MHD) effects together with inlet ramp angle changes. The parameter being optimized is the mass capture at the throat of the inlet, such that spillage effects for less than design Mach numbers are reduced. The control parameters for the optimization include the MHD effects in conjunction with ramp angle changes. To enhance the MHD effects different ionization scenarios depending upon the alignment of the magnetic field are considered. The flow solution is based on the Advection Upstream Splitting Method (AUSM) that accounts for the MHD source terms as well. A numerical Broyden-Flecher-Goldfarb-Shanno- (BFGS-) based procedure is utilized to optimize the inlet mass capture. Numerical validation results compared to published results in the literature as well as the outcome of the optimization procedure are summarized to illustrate the efficacy of the approach.

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