Motion Tracking Technology Research Articles

Do Activity Level Outcome Measures Commonly Used in Neurological Practice Assess Upper-Limb Movement Quality?

Background. Movement is described in terms of task-related end point characteristics in external space and movement quality (joint rotations in body space). Assessment of upper-limb (UL) movement quality can assist therapists in designing effective treatment approaches for retraining lost motor elements and provide more detailed measurements of UL motor improvements over time. Objective. To determine the extent to which current activity level outcome measures used in neurological practice assess UL movement quality. Methods. Outcome measures assessing arm/hand function at the International Classification of Function activity level recommended by neurological clinical practice guidelines were reviewed. Measures assessing the UL as part of a general mobility assessment, those strictly evaluating body function/structure or participation, and paediatric measures were excluded. Results. In all, 15 activity level outcome measures were identified; 9 measures assess how movement is performed by measuring either end point characteristics or movement quality. However, except for the Reaching Performance Scale for Stroke and the Motor Evaluation Scale for Upper Extremity in Stroke Patients, these measures only account for deficits indirectly by giving a partial score if movements are slower or if the person experiences difficulties. Six outcome measures neither assess any parameters related to movement quality, nor distinguish between improvements resulting from motor compensation or recovery of desired movement strategies. Conclusion. Current activity measures may not distinguish recovery from compensation and adequately track changes in movement quality over time. Movement quality may be incorporated into clinical assessment using observational kinematics with or without low-cost motion tracking technology.

Touching The Human Neuron: User-Centric Augmented Reality Viewing and Interaction of in-vivo Cellular Confocal Laser Scanning Microscopy (CLSM) Utilizing High Resolution zStack Data Sets for Applications in Medical Education and Clinical Medicine Using GLASS and Motion Tracking Technology.

This is the first report of a prototype that allows for real-time interaction with high-resolution cellular modules using GLASS© technology. The prototype was developed* using zStack data sets which allow for real-time interaction of low polygon and direct surface models exported from primary source imaging. This paper also discusses potential educational and clinical applications of a wearable, interactive, user-centric, augmented reality visualization of cellular structures. * Prototype was developed using IMARIS© , ImageJ© , MAYA® , 3DCOAT© , UNITY© , ZBrush© , OcculusRift® , LeapMotion© , and output for multiplatform function with Google GLASS© technology as its viewing modality.

Speed-Interactive Treadmill Training Using Smartphone-Based Motion Tracking Technology Improves Gait in Stroke Patients

ABSTRACTThis study was conducted to investigate the effects of speed-interactive treadmill training (SITT) using smartphone-based motion tracking technology on gait in stroke patients. Thirty-four chronic stroke patients were randomly divided into a SITT group (n = 18) and a standard treadmill training (control) group (n = 16). The SITT group underwent smartphone-based SSIT while the control group underwent standard treadmill training. Both groups performed the training for 35 min per session, 3 times per week, for 6 weeks. Both groups used nonmotorized treadmills so that patients could control the speed. Evaluation was conducted during the week before and after the training. The OptoGait system measured gait spatiotemporal parameters. Both groups showed significant improvement in the temporal and spatial gait parameters (p < .05). In the SITT group, compared to the control group, the two-way analysis of variance with repeated measures showed an improvement in the temporal and spatial gait parameters after the intervention period (p < .05). This study confirmed that SITT improved the gait function of stroke patients. Based on this result, the authors propose that SITT, by improving gait, can be used as an effective training method to improve patients' functional activities in the clinic.

Current state of the art of computer-guided implant surgery.

The invention of computerized axial tomography (now known as computerized tomography) and developments of interactive software to allow virtual planning, with the aim to guide the surgery precisely toward a specific target, has dramatically improved general, as well as oral, surgery. Virtual dental implant planning allows for a prosthetically driven approach, resulting in the best possible design of the prosthesis, better esthetics, optimized occlusion and loading. This approach has also changed the surgical paradigm of using extensive flaps to obtain a proper view of the surgical area because flapless implant surgery, with or without immediate loading, has become more predictable. Two types of guided implant surgery protocols - static and dynamic - are described in the literature. The static approach, better known as computer-guided surgery, refers to the use of a tissue-supported surgical template. This reproduces the virtual implant position directly from computerized tomographic data and this information can be converted to guide templates to be used during surgery, with or without raising a mucoperiosteal flap. Dynamic guided surgery, also called navigation, reproduces the virtual implant position directly from computerized tomographic data and uses motion-tracking technology to guide the implant osteotomy preparation. As the technology developed further, different levels of evidence were presented that showed various degrees of accuracy. Several protocols for guided surgery are available in the literature and are distinguished by different guide production techniques, methods of support and drilling/placement protocols. Currently, implant planning software using cone-beam computerized tomography data has made it possible to plan the optical implant position virtually the optimal implant position, taking the surrounding vital anatomic structures and future prosthetic requirements into consideration. This paper summarizes the evolution and ongoing trends in digital and virtual planning and in implant surgery. The purpose of this overview was to clarify the different concepts in guided surgery and their respective advantages, disadvantages and limitations. The outcome of guided surgery is assessed in terms of implant survival, precision and complications. Clinical cases are given to demonstrate briefly the workflow and clinical guidelines for safe use of these approaches.

A PCA-based bio-motion generator to synthesize new patterns of human running

Synthesizing human movement is useful for most applications where the use of avatars is required. These movements should be as realistic as possible and thus must take into account anthropometric characteristics (weight, height, etc.), gender, and the performance of the activity being developed. The aim of this study is to develop a new methodology based on the combination of principal component analysis and partial least squares regression model that can generate realistic motion from a set of data (gender, anthropometry and performance). A total of 18 volunteer runners have participated in the study. The joint angles of the main body joints were recorded in an experimental study using 3D motion tracking technology. A five-step methodology has been employed to develop a model capable of generating a realistic running motion. The described model has been validated for running motion, showing a highly realistic motion which fits properly with the real movements measured. The described methodology could be applied to synthesize any type of motion: walking, going up and down stairs, etc. In future work, we want to integrate the motion in realistic body shapes, generated with a similar methodology and from the same simple original data.

Freehand three-dimensional ultrasound imaging of carotid artery using motion tracking technology

Ultrasound imaging has been extensively used for determining the severity of carotid atherosclerotic stenosis. In particular, the morphological characterization of carotid plaques can be performed for risk stratification of patients. However, using 2D ultrasound imaging for detecting morphological changes in plaques has several limitations. Due to the scan was performed on a single longitudinal cross-section, the selected 2D image is difficult to represent the entire morphology and volume of plaque and vessel lumen. In addition, the precise positions of 2D ultrasound images highly depend on the radiologists’ experience, it makes the serial long-term exams of anti-atherosclerotic therapies are difficult to relocate the same corresponding planes by using 2D B-mode images. This has led to the recent development of three-dimensional (3D) ultrasound imaging, which offers improved visualization and quantification of complex morphologies of carotid plaques. In the present study, a freehand 3D ultrasound imaging technique based on optical motion tracking technology is proposed. Unlike other optical tracking systems, the marker is a small rigid body that is attached to the ultrasound probe and is tracked by eight high-performance digital cameras. The probe positions in 3D space coordinates are then calibrated at spatial and temporal resolutions of 10μm and 0.01s, respectively. The image segmentation procedure involves Otsu’s and the active contour model algorithms and accurately detects the contours of the carotid arteries. The proposed imaging technique was verified using normal artery and atherosclerotic stenosis phantoms. Human experiments involving freehand scanning of the carotid artery of a volunteer were also performed. The results indicated that compared with manual segmentation, the lowest percentage errors of the proposed segmentation procedure were 7.8% and 9.1% for the external and internal carotid arteries, respectively. Finally, the effect of handshaking was calibrated using the optical tracking system for reconstructing a 3D image.

Automated assessment of postural stability system.

The Balance Error Scoring System (BESS) is one of the most commonly used clinical tests to evaluate static postural stability deficits resulting from traumatic brain events and musculoskeletal injury. This test requires a trained operator to visually assess balance and give the subject a performance score based on the number of balance "errors" they committed. Despite being regularly used in several real-world situations, the BESS test is scored by clinician observation and is therefore (a) potentially susceptible to biased and inaccurate test scores and (b) cannot be administered in the absence of a trained provider. The purpose of this research is to develop, calibrate and field test a computerized version of the BESS test using low-cost commodity motion tracking technology. This `Automated Assessment of Postural Stability' (AAPS) system will quantify balance control in field conditions. This research goal is to overcome the main limitations of both the commercially available motion capture systems and the standard BESS test. The AAPS system has been designed to be operated by a minimally trained user and it requires little set-up time with no sensor calibration necessary. These features make the proposed automated system a valuable balance assessment tool to be utilized in the field.

Construct validity of a video-tracking system based on orthogonal cameras approach for objective assessment of laparoscopic skills

This study was aimed to establish the construct validity of a video-tracking system based on orthogonal cameras approach for assessment of laparoscopic psychomotor skills in training environments. The camera-tracking system consists of two webcams placed in orthogonal configuration at a distance of 13.5 cm. The orthogonal cameras employ a color segmentation algorithm to register the 3D motions of the laparoscopic instruments using colored tapes placed on the distal end. For construct validity, 31 participants (4 experts and 27 residents) performed three training tasks in a laparoscopic box trainer with the built-in orthogonal cameras system. Eleven motion-related parameters were used to evaluate their performance. Statistical analysis was performed, and results between two groups were compared using a Mann-Whitney U-test. Construct validity results showed statistical differences in almost all motion-related parameters for assessment of laparoscopic technical skills. Results demonstrated that the orthogonal video-based tracking system was able to differentiate laparoscopic experience between experts and trainees surgeons. The orthogonal cameras system was successfully validated in a laparoscopic box trainer. This video-based tracking system was able to distinguish performance between experts and trainees surgeons, showing its potential as a reliable tool to assess laparoscopic psychomotor skills. The orthogonal cameras allow incorporating the advantages of this video motion-tracking technology with the benefits of the traditional laparoscopic box trainers, creating realistic haptic feedback and allowing the evaluation of psychomotor skills of the surgeons.

Movement-Tracking Technology Could Identify Speech Disorders in Children

Movement-Tracking Technology Could Identify Speech Disorders in Children

Preliminary Investigation of an Innovative Digital Motion Analysis Device for Badminton Athlete Performance Evaluation

Badminton is a sport that combines several different physical aspects. At a professional level, the sport demands excellent fitness criteria namely the player's aerobic stamina, agility, strength, speed as well as precision. This study fundamentally entails the development of an innovative training system that incorporates technology that could improve the athlete's performance. Although existing motion tracking technology can provide reliable and accurate tracking results, nonetheless, the product cost and complexity keeps them away from being employed in most sports. This investigation involves the comparison between Kinect Technology and inertial measurement unit (IMU). The kinematic movement of the arm from wrist until shoulder was observed in this study for the purpose of investigating the difference between the acceleration of skeleton detected by the Kinect motion tracking and a low-cost IMU. The results obtained were found to be promising, and it is important in enabling pattern recognition of different badminton strokes in the next stage of the study. The movement of the right-hand wrist is tracked by Microsoft Kinect that can track the skeleton of the player whilst the IMU that measures the acceleration is attached at the right-hand wrist. Although the acceleration of the wrist may readily be obtained from the IMU, the acceleration from Kinect may only be obtained through mathematical manipulation. It was found that the accelerations of the upper limb movement from both IMU and Kinect demonstrated good agreement.

A simple and inexpensive test-rig for evaluating the performance of motion sensors used in movement disorders research.

Since the advent of electromyogram recording, precise measures of tremor and gait have been used to study movement disorders such as Parkinson's disease. Now, a wide range of accelerometers and other motion-tracking technologies exist to better inform researchers and clinicians, yet such systems are rarely tested for accuracy or suitability before use. Our inexpensive test-rig can produce sinusoidal displacements using a simple cantilever system driven by a subwoofer. Controlled sinusoids were generated using computer software, and the displacement amplitudes of the test-rig were verified with fiducial marker tracking. To illustrate the use of the test-rig, we evaluated an accelerometer and an electromagnetic motion tracker. Accelerometry recordings were accurate to within±0.09g of actual peak-to-peak amplitude with a frequency response close to unity gain between 1 and 20Hz. The electromagnetic sensor underestimated peak displacement by 2.68mm, which was largely due to a diminishing gain with increasing frequency. Both sensors had low distortion. Overall sensitivity was limited by noise for the accelerometer and quantisation resolution for the electromagnetic sensor. Our simple and low-cost test-rig can be used to bench-test sensors used in movement disorders research. It was able to produce reliable sinusoidal displacements and worked across the 1- to 20-Hz frequency range.

Appearance, motion, and embodiment: unpacking avatars by fine‐grained communication analysis

SummaryThanks to the maturity of motion tracking technologies, it became easy and inexpensive to use avatars that reflect the user's facial and body motions in real time. There is a possibility that those real‐time avatars can serve as a substitute for videos in distant communication. We conducted two experiments to confirm positive effects of avatars on distant communication. In the first experiment, the subjects watched a conversation partner's video, avatar, photo, or nothing when speaking to the partner. Because the video and avatar delivered the partner's motion while the video and photo delivered the partner's appearance, we were able to observe the effects of the motion and appearance separately. As a result, we found that presenting the motion via a video or an avatar increased the degree of the smoothness of speaking to the partner, but the appearance did not significantly affect such an influence. In the second experiment, we compared the avatar and teleoperated robot to find how a physical embodiment influences the degree of the smoothness of speech. Teleoperated robots resemble avatars in transmitting the user's body motions without disclosing the user's appearance but differ in reflecting these motions onto a robot that has a physical embodiment. We predicted that the robot produces smoother speech because the physical embodiment might make the body motions recognizable. However, the robot decreased the degree of the smoothness of speech against our expectation. The results of these experiments showed that real‐time avatars that present only body motions are enough to smooth distant communication. Copyright © 2014 John Wiley &amp; Sons, Ltd.

An Approach to Physical Rehabilitation Using State-of-the-art Virtual Reality and Motion Tracking Technologies

Abstract This paper explores an approach to physical rehabilitation using state-of-the-art technologies in virtual reality and motion tracking; in particular, Oculus Rift DK2 (released in July, 2014) and Intel RealSense (released in November, 2014) are used. A game is developed which requires from the patient to perform an established set of abduction and adduction arm movements to achieve rotator cuff rehabilitation after injury. While conduct of clinical trials is outside the scope of this work, experts in physical rehabilitation working in the medical field have carried out a preliminary evaluation, showing encouraging results.

Manual action, fitting, and spatial planning: Relating objects by young children

This study uses motion tracking technology to provide a new way of addressing the development of the ability to prospectively orient objects with respect to one another. A group of toddlers between 16 and 33months of age (N=30) were studied in an object fitting task while they wore reflective markers on their hands to track spatial adjustments in three dimensions. Manual displacements of the handheld object were separated into translations and rotations. Results revealed that younger children largely used a two-step approach in which they initially translate an object to a target and subsequently attempt to rotate the object to match the target. In contrast, older children evidence more advanced spatial planning and integrate translational and rotational components throughout the entire period when they are transporting the object to the target. Additionally, at the oldest ages, children show even further improvements in coordinating translations and rotations by using relatively shorter translations (i.e., covering less distance) and by avoiding unnecessary rotations of the object. More broadly, the results offer insights into how manual problem solving becomes more efficient and planful during the toddler years.

MP14-13 THE FLUORO-LESS C-ARM PERCUTANEOUS ACCESS TRAINER

You have accessJournal of UrologyTechnology & Instruments: Surgical Education & Skills Assessment II1 Apr 2014MP14-13 THE FLUORO-LESS C-ARM PERCUTANEOUS ACCESS TRAINER Domenico Veneziano, Arthur Smith, Troy Reihsen, Jason Speich, and Robert Sweet Domenico VenezianoDomenico Veneziano More articles by this author , Arthur SmithArthur Smith More articles by this author , Troy ReihsenTroy Reihsen More articles by this author , Jason SpeichJason Speich More articles by this author , and Robert SweetRobert Sweet More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.641AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Achieving proper renal access is one of the most challenging skill-sets for PCNL. Parallax of the proper calyx with c-arm is a core learning objective. Existing training systems use virtual reality(VR) or fluoro-assisted biologic and synthetic models. VR models have limitations and are expensive and fluoroscopy is impractical and is associated with unnecessary exposure to radiation. We report the development and initial validation of a fluoro-less percutaneous renal access trainer. METHODS A mini C-arm was designed and 3D printed. Two videocameras were mounted on the anterior and posterior portion of the C. The C was designed to tilt and rainbow. A clear flank model was created with a silicon material with a cast of a University of Minnesota SimPORTAL calyceal model in it filled with fluid. The silicon model has been then covered with a "blue screen" skin-like, colored material and provided with a physical reproduction of the 10th-12th ribs. The two cameras have been connected to a computer for image processing to produce the final on-screen image. RESULTS The C-arm navigation trainer has face and content validity for training percutaneous access. It does so successfully without radiation exposure. The novel double camera system and the image processing software were able to obtain visual information enough to accomplish correctly the training tasks, without expensive additional 3d motion tracking technologies. CONCLUSIONS The fluoroscopy-less C-arm navigation trainer accurately replicates the functions of a real X-ray system, without any radiation exposure related issues, regardless the time it takes to complete the training sessions. The usability of a perc model, as well as of any other specifically designed anatomical silicon models, make it a low cost, feasible instrument for training. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e173 Peer Review Report Advertisement Copyright & Permissions© 2014MetricsAuthor Information Domenico Veneziano More articles by this author Arthur Smith More articles by this author Troy Reihsen More articles by this author Jason Speich More articles by this author Robert Sweet More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Synchronization of speech and gesture: Evidence for interaction in action.

Language and action systems are highly interlinked. A critical piece of evidence is that speech and its accompanying gestures are tightly synchronized. Five experiments were conducted to test 2 hypotheses about the synchronization of speech and gesture. According to the interactive view, there is continuous information exchange between the gesture and speech systems, during both their planning and execution phases. According to the ballistic view, information exchange occurs only during the planning phases of gesture and speech, but the 2 systems become independent once their execution has been initiated. In all experiments, participants were required to point to and/or name a light that had just lit up. Virtual reality and motion tracking technologies were used to disrupt their gesture or speech execution. Participants delayed their speech onset when their gesture was disrupted. They did so even when their gesture was disrupted at its late phase and even when they received only the kinesthetic feedback of their gesture. Also, participants prolonged their gestures when their speech was disrupted. These findings support the interactive view and add new constraints on models of speech and gesture production.

The adaptive Kalman filter based on fuzzy logic for inertial motion capture system

In the inertial motion capture system, the model complexity and the large amount of computation make the completion of the orientation estimation algorithm rely solely on PC. Because the data processing speed is slow, it is difficult to realize high-speed motion tracking in the embedded system. In order to further expand the application of the motion tracking technology, this paper introduces a two-step Kalman filter, which is suitable for the embedded system. The filter is composed of two sub filters, and is adaptively adjusted based on the variance matching of fuzzy logic. IMU orientation is calculated based on the filtered acceleration vector and the estimated yaw. This approach simplifies the mathematical model, reduces the matrix operations and improves the speed of computation.

Assessment of area strain, twist, torsion and rotation in fetal echocardiography using three-dimensional (3D) Wall Motion Tracking Technology

Purpose: To demonstrate the possible application of 3D speckle tracking enabling to do real 3D based analysis of advanced three-dimensional myocardial motion patterns such as area strain, rotation, twist and torsion in fetal echocardiography.

OP04.10: Assessment of area strain, twist, torsion and rotation in fetal echocardiography using three‐dimensional (3D) wall motion tracking technology

<scp>OP04</scp>.10: Assessment of area strain, twist, torsion and rotation in fetal echocardiography using three‐dimensional (<scp>3D</scp>) wall motion tracking technology

Gestural Control of a Remote Robotic Manipulator

Recent technological developments in motion tracking technology have lowered the price of motioncapture devices to the extent that nearly anyone can accurately model the dimensions and movement of the human body. The system described herein was the result of an attempt to capitalize on the aforementioned low-cost motion-capture technology to develop an accurate human-robot interface which relies on translating natural forelimb movement into servo actuation commands to control a robotic arm. Given that most endeavors into robotics are interdisciplinary, this work incorporates input from electrical engineering, mechanical engineering, computer science, and human-robot interface design. This system was specifically designed, in cooperation with NASA, to be used by an operator in a low-gravity environment, but the number of possible applications are substantial. These applications include, but are not limited to, military explosive ordnance disposal, remote maintenance in hostile environments, and safe exploration into hazardous environments.