Calibration and Mapping of a Human Hand for Dexterous Telemanipulation

2000 ◽  
Author(s):  
Weston B. Griffin ◽  
Ryan P. Findley ◽  
Michael L. Turner ◽  
Mark R. Cutkosky
Keyword(s):  
Accurate Determination ◽  
Linear Mapping ◽  
Virtual Object ◽  
Human Hand ◽  
Robot Hand ◽  
Calibration Scheme ◽  
Instrumented Glove ◽  
Kinematic Mapping ◽  
Mapping Scheme

Abstract This paper presents a calibration scheme and kinematic mapping to support dexterous telemanipulation. The calibration scheme is intended for use with an instrumented glove and permits an accurate determination of the intended motions of a virtual object grasped between a human operator’s thumb and index finger. The motions of the virtual object are then mapped to analogous motions of a scaled virtual object held in a two-fingered robot hand. A non-linear mapping scheme allows better utilization of the human and robot hand workspaces.

Kinematic Mapping and Calibration of the Thumb Motions for Teleoperating a Humanoid Robot Hand

2011 ◽  
Author(s):  
Lei Cui ◽  
Ugo Cupcic ◽  
Jian S. Dai
Keyword(s):  
Humanoid Robot ◽  
Index Finger ◽  
Input Device ◽  
Human Hand ◽  
Robot Hand ◽  
Optimization Formulation ◽  
Kinematic Mapping ◽  
Dexterous Hand ◽  
Tip Position ◽  
Hand Pose

Mapping and calibration from a human hand to a robot hand pose a challenge due to their differences in kinematic structures. This paper uses the CyberGlove® as the input device for telemanipulating an object with the thumb and the index finger of the Shadow® Dexterous Hand™, with the focus not only on the position but also on the orientation of the thumb fingertip because it is found through experiments conducted on the Shadow Hand that the calibration of tip position alone can lead to unacceptable grasping postures. This paper develops an experiment protocol and proposes a nonlinear optimization formulation that makes the normals of the surfaces of the thumb and index fingertips within the friction cone while subject to fingertip position constraint. The results are verified to be accurate enough to conduct the telemanipulation.

Improved Procedure for Determining Water Activity in a High Range

1986 ◽  
Vol 69 (6) ◽  
pp. 952-956
Author(s):  
Walter D Flom ◽  
Nobumasa Tanaka ◽  
Susan K Kovats ◽  
Lynda M Finn
Keyword(s):  
Water Activity ◽  
Calibration Curve ◽  
Accurate Determination ◽  
Calibration Procedure ◽  
Calibration Scheme ◽  
Before And After ◽  
Single Determination ◽  
Precision And Accuracy ◽  
High Range

Abstract A procedure for accurate determination of water activity (aw) in a high range (aw between 0.920 and 0.970) using a Beckman Hygroline apparatus was devised because the prescribed calibration procedure was inadequate. This new procedure uses NaCl solutions as standards and the aw values for NaCl solutions reported by Robinson as the reference scale. A quadratic calibration curve: Recorder reading = b0 + b1aw + b2aw2 was established for each sensor. A 3-point calibration scheme, taking measurements of 0.9m (molal), 1.6m, and 2.4m NaCl solutions, was used before and after a series of aw measurements of samples to estimate b0 and verify the constancy of shape of the calibration curve. The equation was solved for aw to convert each recorder reading to an aw value on Robinson’s scale. This procedure yielded precision and accuracy levels for a single determination of 0.0009 and 0.0013 aw unit, respectively. Accuracy of 0.0009 aw unit was obtained by averaging 2 determinations on different sensors.

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

Fast calibration of CBED patterns for quantitative analysis

1993 ◽  
Vol 51 ◽  
pp. 674-675
Author(s):  
M.A. Gribelyuk ◽  
M. Rühle
Keyword(s):  
Reciprocal Lattice ◽  
Accurate Determination ◽  
Incident Beam ◽  
Crystal Thickness ◽  
Structure Model ◽  
Beam Direction ◽  
Transmitted Beam ◽  
Reciprocal Vector ◽  
On Line

A new method is suggested for the accurate determination of the incident beam direction K, crystal thickness t and the coordinates of the basic reciprocal lattice vectors V1 and V2 (Fig. 1) of the ZOLZ plans in pixels of the digitized 2-D CBED pattern. For a given structure model and some estimated values Vest and Kest of some point O in the CBED pattern a set of line scans AkBk is chosen so that all the scans are located within CBED disks.The points on line scans AkBk are conjugate to those on A0B0 since they are shifted by the reciprocal vector gk with respect to each other. As many conjugate scans are considered as CBED disks fall into the energy filtered region of the experimental pattern. Electron intensities of the transmitted beam I0 and diffracted beams Igk for all points on conjugate scans are found as a function of crystal thickness t on the basis of the full dynamical calculation.

Computer-Assisted High-Re Solution TEM

1990 ◽  
Vol 48 (1) ◽  
pp. 162-163
Author(s):  
F.A. Ponce ◽  
H. Hikashi
Keyword(s):  
Signal To Noise Ratio ◽  
Accurate Determination ◽  
Computer Software ◽  
Video Camera ◽  
Image Contrast ◽  
Objective Lens ◽  
Computer Assisted ◽  
Optical Parameters ◽  
Astigmatism Correction

The determination of the atomic positions from HRTEM micrographs is only possible if the optical parameters are known to a certain accuracy, and reliable through-focus series are available to match the experimental images with calculated images of possible atomic models. The main limitation in interpreting images at the atomic level is the knowledge of the optical parameters such as beam alignment, astigmatism correction and defocus value. Under ordinary conditions, the uncertainty in these values is sufficiently large to prevent the accurate determination of the atomic positions. Therefore, in order to achieve the resolution power of the microscope (under 0.2nm) it is necessary to take extraordinary measures. The use of on line computers has been proposed [e.g.: 2-5] and used with certain amount of success.We have built a system that can perform operations in the range of one frame stored and analyzed per second. A schematic diagram of the system is shown in figure 1. A JEOL 4000EX microscope equipped with an external computer interface is directly linked to a SUN-3 computer. All electrical parameters in the microscope can be changed via this interface by the use of a set of commands. The image is received from a video camera. A commercial image processor improves the signal-to-noise ratio by recursively averaging with a time constant, usually set at 0.25 sec. The computer software is based on a multi-window system and is entirely mouse-driven. All operations can be performed by clicking the mouse on the appropiate windows and buttons. This capability leads to extreme friendliness, ease of operation, and high operator speeds. Image analysis can be done in various ways. Here, we have measured the image contrast and used it to optimize certain parameters. The system is designed to have instant access to: (a) x- and y- alignment coils, (b) x- and y- astigmatism correction coils, and (c) objective lens current. The algorithm is shown in figure 2. Figure 3 shows an example taken from a thin CdTe crystal. The image contrast is displayed for changing objective lens current (defocus value). The display is calibrated in angstroms. Images are stored on the disk and are accessible by clicking the data points in the graph. Some of the frame-store images are displayed in Fig. 4.

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