Factors Influencing Accuracy of Screw Displacement Axis Detection With a D.C.-Based Electromagnetic Tracking System

1998 ◽  
Vol 120 (3) ◽  
pp. 431-435 ◽  
Author(s):  
M. Bottlang ◽  
J. L. Marsh ◽  
T. D. Brown
Keyword(s):  
Motion Tracking ◽  
Tracking System ◽  
Three Dimensional ◽  
Joint Motion ◽  
Electromagnetic Tracking ◽  
Source Data ◽  
Surgical Setting ◽  
Smoothing Procedure ◽  
Electromagnetic Tracking System ◽  
Single Receiver

Recent technical improvements and cost reductions in electromagnetic motion tracking systems invite their application to motion axis determination in the surgical setting. After evaluation of the accuracy of a state-of-the-art D. C. electromagnetic tracking system, which generates complete three-dimensional kinematic outputs from just a single receiver, we calculated screw displacement axes (SDA’s) from its source data. The accuracy of SDA determination from such source data was evaluated for various rotational increment sizes around a revolute joint. A novel smoothing procedure, customized for this type of source data, was developed, enabling SDA detection from incremental rotations of less than 1 deg, at an accuracy appropriate for intra-operative measurement of human joint motion. Examples of SDA determination are given for motion tracking of a ball joint and of the elbow articulation.

Tracker Modalities for Virtual Environments: A Comparison of Some Performance Characteristics

2002 ◽  
Author(s):  
Roglenda Repp ◽  
Uma Jayaram
Keyword(s):  
Virtual Environments ◽  
Motion Tracking ◽  
Tracking System ◽  
Temporal Stability ◽  
Performance Characteristics ◽  
Electromagnetic Tracking ◽  
Tracking Systems ◽  
Static Distortion ◽  
Electromagnetic Tracking System ◽  
Virtual Reality Application

In this paper the authors present a comparison of some performance characteristics of two motion tracking modalities for use in a virtual environment. Ascension Technology’s Flock of Birds is an electromagnetic tracking system. Intersense’s IS-600 uses a combination of ultrasonic, infrared, and inertial principles. Case studies were performed for both tracking systems to study static distortion, temporal stability, and the effect of metal. The requirements of the virtual reality application would ultimately guide the choice of the tracker modality.

Effect of Variations in Calcaneocuboid Fusion Technique on Kinematics of the Normal Hindfoot

1998 ◽  
Vol 19 (1) ◽  
pp. 19-25 ◽  
Author(s):  
Andrew Sands ◽  
John Early ◽  
Richard M Harrington ◽  
Allan F Tencer ◽  
Randal P Ching ◽  
...  
Keyword(s):  
Tracking System ◽  
Plantar Flexion ◽  
Neutral Position ◽  
Joint Motion ◽  
Electromagnetic Tracking ◽  
Tibiotalar Joint ◽  
Lateral Column ◽  
Calcaneocuboid Joint ◽  
And Inversion ◽  
Electromagnetic Tracking System

Calcaneocuboid fusion with lengthening of the lateral column of the foot has been advocated as a method of treating flatfoot deformity. This study was designed to determine how the length of the lateral column chosen or the position of the foot selected when performing this fusion affect hindfoot kinematics in normal cadaver feet. An electromagnetic tracking system was used to monitor the positions of the talus, calcaneus, navicular, and cuboid while the intact cadaver feet were moved passively and then under reproducible loads. Calcaneocuboid fusion was then performed on these feet first with the feet in neutral position and the lateral column of normal length, then lengthened 10 mm or shortened 5 mm, and then with the lateral column lengthened 10 mm and the feet positioned in plantar flexion and eversion or dorsiflexion and inversion. Kinematic measurements were made at each stage using the same loads. Fusing the calcaneocuboid joint with lengthening or shortening the lateral column and the feet in neutral position did not affect hindfoot joint motion compared with intact. Changing the position of the foot for fusion, however, resulted in significant decreases in motion in the talocalcaneal and talonavicular joints. Tibiotalar joint motion was unaffected. This study, therefore, demonstrates that when fusing the calcaneocuboid joint, attention should be paid to maintaining a neutral position of the foot.

scholarly journals Accuracy and repeatability of wrist joint angles in boxing using an electromagnetic tracking system

2019 ◽  
Vol 23 (1) ◽  
Author(s):  
Ian T. Gatt ◽  
Tom Allen ◽  
Jon Wheat
Keyword(s):  
Wrist Joint ◽  
Tracking System ◽  
Testing Procedure ◽  
Electromagnetic Tracking ◽  
Good Reliability ◽  
Flexion Extension ◽  
In Vivo Testing ◽  
Accuracy And Repeatability ◽  
Electromagnetic Tracking System

AbstractThe hand-wrist region is reported as the most common injury site in boxing. Boxers are at risk due to the amount of wrist motions when impacting training equipment or their opponents, yet we know relatively little about these motions. This paper describes a new method for quantifying wrist motion in boxing using an electromagnetic tracking system. Surrogate testing procedure utilising a polyamide hand and forearm shape, and in vivo testing procedure utilising 29 elite boxers, were used to assess the accuracy and repeatability of the system. 2D kinematic analysis was used to calculate wrist angles using photogrammetry, whilst the data from the electromagnetic tracking system was processed with visual 3D software. The electromagnetic tracking system agreed with the video-based system (paired t tests) in both the surrogate (< 0.2°) and quasi-static testing (< 6°). Both systems showed a good intraclass coefficient of reliability (ICCs > 0.9). In the punch testing, for both repeated jab and hook shots, the electromagnetic tracking system showed good reliability (ICCs > 0.8) and substantial reliability (ICCs > 0.6) for flexion–extension and radial-ulnar deviation angles, respectively. The results indicate that wrist kinematics during punching activities can be measured using an electromagnetic tracking system.

scholarly journals Multi-sensor three-dimensional Monte Carlo localization for long-term aerial robot navigation

2017 ◽  
Vol 14 (5) ◽  
pp. 172988141773275 ◽  
Author(s):  
Francisco J Perez-Grau ◽  
Fernando Caballero ◽  
Antidio Viguria ◽  
Anibal Ollero
Keyword(s):  
Monte Carlo ◽  
Motion Tracking ◽  
Robot Navigation ◽  
Tracking System ◽  
Three Dimensional ◽  
Measurement Unit ◽  
Indoor Environments ◽  
Localization Algorithm ◽  
Monte Carlo Localization ◽  
Motion Tracking System

This article presents an enhanced version of the Monte Carlo localization algorithm, commonly used for robot navigation in indoor environments, which is suitable for aerial robots moving in a three-dimentional environment and makes use of a combination of measurements from an Red,Green,Blue-Depth (RGB-D) sensor, distances to several radio-tags placed in the environment, and an inertial measurement unit. The approach is demonstrated with an unmanned aerial vehicle flying for 10 min indoors and validated with a very precise motion tracking system. The approach has been implemented using the robot operating system framework and works smoothly on a regular i7 computer, leaving plenty of computational capacity for other navigation tasks such as motion planning or control.

Electromagnetic tracking system for minimal invasive interventions using a C-arm system with CT option: first clinical results

2008 ◽  
Author(s):  
Markus Nagel ◽  
Martin Hoheisel ◽  
Ulrich Bill ◽  
Klaus Klingenbeck-Regn ◽  
Willi A. Kalender ◽  
...  
Keyword(s):  
Tracking System ◽  
Clinical Results ◽  
Minimal Invasive ◽  
Electromagnetic Tracking ◽  
Electromagnetic Tracking System
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