Comparison of 3D Joint Angles Measured With the Kinect 2.0 Skeletal Tracker Versus a Marker-Based Motion Capture System

2017 ◽  
Vol 33 (2) ◽  
pp. 176-181 ◽  
Author(s):  
Trent M. Guess ◽  
Swithin Razu ◽  
Amirhossein Jahandar ◽  
Marjorie Skubic ◽  
Zhiyu Huo
Keyword(s):  
Correlation Coefficient ◽  
Vertical Jump ◽  
Human Motion ◽  
Microsoft Kinect ◽  
Joint Angles ◽  
3 Dimensional ◽  
Hip Abduction ◽  
Rms Error ◽  
Skeletal Model ◽  
Drop Vertical Jump

The Microsoft Kinect is becoming a widely used tool for inexpensive, portable measurement of human motion, with the potential to support clinical assessments of performance and function. In this study, the relative osteokinematic Cardan joint angles of the hip and knee were calculated using the Kinect 2.0 skeletal tracker. The pelvis segments of the default skeletal model were reoriented and 3-dimensional joint angles were compared with a marker-based system during a drop vertical jump and a hip abduction motion. Good agreement between the Kinect and marker-based system were found for knee (correlation coefficient = 0.96, cycle RMS error = 11°, peak flexion difference = 3°) and hip (correlation coefficient = 0.97, cycle RMS = 12°, peak flexion difference = 12°) flexion during the landing phase of the drop vertical jump and for hip abduction/adduction (correlation coefficient = 0.99, cycle RMS error = 7°, peak flexion difference = 8°) during isolated hip motion. Nonsagittal hip and knee angles did not correlate well for the drop vertical jump. When limited to activities in the optimal capture volume and with simple modifications to the skeletal model, the Kinect 2.0 skeletal tracker can provide limited 3-dimensional kinematic information of the lower limbs that may be useful for functional movement assessment.

scholarly journals Development and Validation of a Portable and Inexpensive Tool to Measure the Drop Vertical Jump Using the Microsoft Kinect V2

2017 ◽  
Vol 9 (6) ◽  
pp. 537-544 ◽  
Author(s):  
Aaron D. Gray ◽  
Brad W. Willis ◽  
Marjorie Skubic ◽  
Zhiyu Huo ◽  
Swithin Razu ◽  
...  
Keyword(s):  
Motion Analysis ◽  
Female Athletes ◽  
Vertical Jump ◽  
Intraclass Correlation ◽  
Microsoft Kinect ◽  
Screening Tools ◽  
Initial Contact ◽  
Adolescent Female ◽  
Kinect V2 ◽  
Drop Vertical Jump

Background: Noncontact anterior cruciate ligament (ACL) injury in adolescent female athletes is an increasing problem. The knee-ankle separation ratio (KASR), calculated at initial contact (IC) and peak flexion (PF) during the drop vertical jump (DVJ), is a measure of dynamic knee valgus. The Microsoft Kinect V2 has shown promise as a reliable and valid marker-less motion capture device. Hypothesis: The Kinect V2 will demonstrate good to excellent correlation between KASR results at IC and PF during the DVJ, as compared with a “gold standard” Vicon motion analysis system. Study Design: Descriptive laboratory study. Level of Evidence: Level 2. Methods: Thirty-eight healthy volunteer subjects (20 male, 18 female) performed 5 DVJ trials, simultaneously measured by a Vicon MX-T40S system, 2 AMTI force platforms, and a Kinect V2 with customized software. A total of 190 jumps were completed. The KASR was calculated at IC and PF during the DVJ. The intraclass correlation coefficient (ICC) assessed the degree of KASR agreement between the Kinect and Vicon systems. Results: The ICCs of the Kinect V2 and Vicon KASR at IC and PF were 0.84 and 0.95, respectively, showing excellent agreement between the 2 measures. The Kinect V2 successfully identified the KASR at PF and IC frames in 182 of 190 trials, demonstrating 95.8% reliability. Conclusion: The Kinect V2 demonstrated excellent ICC of the KASR at IC and PF during the DVJ when compared with the Vicon system. A customized Kinect V2 software program demonstrated good reliability in identifying the KASR at IC and PF during the DVJ. Clinical Relevance: Reliable, valid, inexpensive, and efficient screening tools may improve the accessibility of motion analysis assessment of adolescent female athletes.

scholarly journals NEURAL ACTIVITY AND LANDING BIOMECHANICS: EXPLORING THE RELATIONSHIPS BETWEEN THE BRAIN, BODY, AND ACL INJURY-RISK

2021 ◽  
Vol 9 (7_suppl3) ◽  
pp. 2325967121S0015
Author(s):  
Cody R. Criss ◽  
Dustin R. Grooms ◽  
Jed A. Diekfuss ◽  
Manish Anand ◽  
Alexis B. Slutsky-Ganesh ◽  
...  
Keyword(s):  
Neural Activity ◽  
Injury Risk ◽  
Neural Control ◽  
Motor Coordination ◽  
Cruciate Ligament ◽  
Vertical Jump ◽  
Frontal Plane ◽  
Peak Knee ◽  
Knee Abduction ◽  
Drop Vertical Jump

Background: Anterior cruciate ligament (ACL) injuries predominantly occur via non-contact mechanisms, secondary to motor coordination errors resulting in aberrant frontal plane knee loads that exceed the thresholds of ligament integrity. However, central nervous system processing underlying high injury-risk motor coordination errors remain unknown, limiting the optimization of current injury reduction strategies. Purpose: To evaluate the relationships between brain activity during motor tasks with injury-risk loading during a drop vertical jump. Methods: Thirty female high school soccer players (16.10 ± 0.87 years, 165.10 ± 4.64 cm, 63.43 ± 8.80 kg) were evaluated with 3D biomechanics during a standardized drop vertical jump from a 30 cm box and peak knee abduction moment was extracted as the injury-risk variable of interest. A neuroimaging session to capture neural activity (via blood-oxygen-level-dependent signal) was then completed which consisted of 4 blocks of 30 seconds of repeated bilateral leg press action paced to a metronome beat of 1.2 Hz with 30 seconds rest between blocks. Knee abduction moment was evaluated relative to neural activity to identify potential neural contributors to injury-risk. Results: There was a direct relationship between increased landing knee abduction moment and increased neural activation within regions corresponding to the lingual gyrus, intracalcarine cortex, posterior cingulate cortex, and precuneus (r2= 0.68, p corrected < .05, z max > 3.1; Table 1 & Figure 1). Conclusion: Elevated activity in regions that integrate sensory, spatial, and attentional information may contribute to elevated frontal plane knee loads during landing. Interestingly, a similar activation pattern related to high-risk landing mechanics has been found in those following injury, indicating that predisposing factors to injury may be accentuated by injury or that modern rehabilitation does not recover prospective neural control deficits. These data uncover a potentially novel brain marker that could guide the discovery of neural-therapeutic targets that reduce injury risk beyond current prevention methods. [Table: see text][Figure: see text]

scholarly journals Relationship Between 2-Dimensional Frontal Plane Measures and the Knee Abduction Angle During the Drop Vertical Jump

2019 ◽  
Vol 28 (4) ◽  
Author(s):  
Brad W. Willis ◽  
Katie Hocker ◽  
Swithin Razu ◽  
Aaron D. Gray ◽  
Marjorie Skubic ◽  
...  
Keyword(s):  
Motion Capture ◽  
Vertical Jump ◽  
Frontal Plane ◽  
Ligament Injury ◽  
Coefficient Of Determination ◽  
Abduction Angle ◽  
Initial Contact ◽  
Knee Abduction ◽  
The Relationship ◽  
Drop Vertical Jump

Context: Knee abduction angle (KAA), as measured by 3-dimensional marker-based motion capture systems during jump-landing tasks, has been correlated with an elevated risk of anterior cruciate ligament injury in females. Due to the high cost and inefficiency of KAA measurement with marker-based motion capture, surrogate 2-dimensional frontal plane measures have gained attention for injury risk screening. The knee-to-ankle separation ratio (KASR) and medial knee position (MKP) have been suggested as potential frontal plane surrogate measures to the KAA, but investigations into their relationship to the KAA during a bilateral drop vertical jump task are limited. Objective: To investigate the relationship between KASR and MKP to the KAA during initial contact of the bilateral drop vertical jump. Design: Descriptive. Setting: Biomechanics laboratory. Participants: A total of 18 healthy female participants (mean age: 24.1 [3.88] y, mass: 65.18 [10.34] kg, and height: 1.63 [0.06] m). Intervention: Participants completed 5 successful drop vertical jump trials measured by a Vicon marker-based motion capture system and 2 AMTI force plates. Main Outcome Measure: For each jump, KAA of the tibia relative to the femur was measured at initial contact along with the KASR and MKP calculated from planar joint center data. The coefficient of determination (r2) was used to examine the relationship between the KASR and MKP to KAA. Results: A strong linear relationship was observed between MKP and KAA (r2 = .71), as well as between KASR and KAA (r2 = .72). Conclusions: Two-dimensional frontal plane measures show strong relationships to the KAA during the bilateral drop vertical jump.

Females with patellofemoral pain have impaired impact absorption during a single-legged drop vertical jump

2019 ◽  
Vol 68 ◽  
pp. 346-351 ◽  
Author(s):  
Guilherme S. Nunes ◽  
Christian John Barton ◽  
Fábio Viadanna Serrão
Keyword(s):  
Vertical Jump ◽  
Patellofemoral Pain ◽  
Impact Absorption ◽  
Drop Vertical Jump

Analysis and Design of an Auxiliary Catching Arm for an Apple Picking Robot

2020 ◽  
Author(s):  
Andrew Porter ◽  
Jassim Alhamid ◽  
Changki Mo ◽  
John Miller ◽  
Joseph Iannelli ◽  
...  
Keyword(s):  
Lagrangian Mechanics ◽  
Drop Height ◽  
Joint Angles ◽  
3 Dimensional ◽  
Analysis And Design ◽  
Revolute Joints ◽  
Linkage Design ◽  
Workspace Analysis ◽  
Forward Linkage ◽  
Mechanical Linkage

Abstract The newly designed 3-dimensional catching robot consists of three revolute joints where the forward linkage is a parallelogram mechanism for keeping the catching end-effector parallel to the picking manipulator’s base. A virtual apple field of 505 apples, designed to test the picking abilities of 7 DOF arm, was used to determine the capabilities of this new catching arm design. The target catching efficiency was 90% for the provided virtual apple field with a maximum drop height of 30 cm. The target coordinates for each virtual apple were found by computer simulation in MATLAB. Geometric parameters were selected such that the catching manipulator could reach every possible drop position in the picking manipulator’s workspace. The design was completed, fabricated, and validated, utilizing the elegant mechanical linkage design. The workspace analysis showed that it had an acceptable 93% catching efficiency, and as the drop height increased, the efficiency approaches 100%. Definitive inverse-kinematics provided exact joint angles required to catch all catchable apples inside of the workspace. Using these angles, the general equation of motion, using Lagrangian mechanics, yielded the required torque outputs of each of the three motors on the arm. Validation of these torques through laboratory experimentation was considered adequate.

scholarly journals Projection Analysis Optimization for Human Transition Motion Estimation

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Wanyi Li ◽  
Feifei Zhang ◽  
Qiang Chen ◽  
Qian Zhang
Keyword(s):  
Video Game ◽  
Human Motion ◽  
High Dimensional ◽  
Dynamical Models ◽  
Excellent Performance ◽  
3 Dimensional ◽  
Latent Space ◽  
Projection Analysis ◽  
Low Dimensional ◽  
Working Efficiency

It is a difficult task to estimate the human transition motion without the specialized software. The 3-dimensional (3D) human motion animation is widely used in video game, movie, and so on. When making the animation, human transition motion is necessary. If there is a method that can generate the transition motion, the making time will cost less and the working efficiency will be improved. Thus a new method called latent space optimization based on projection analysis (LSOPA) is proposed to estimate the human transition motion. LSOPA is carried out under the assistance of Gaussian process dynamical models (GPDM); it builds the object function to optimize the data in the low dimensional (LD) space, and the optimized data in LD space will be obtained to generate the human transition motion. The LSOPA can make the GPDM learn the high dimensional (HD) data to estimate the needed transition motion. The excellent performance of LSOPA will be tested by the experiments.

scholarly journals EMG-Informed Musculoskeletal Modeling to Estimate Realistic Knee Anterior Shear Force During Drop Vertical Jump in Female Athletes

2019 ◽  
Vol 47 (12) ◽  
pp. 2416-2430 ◽  
Author(s):  
Alessandro Navacchia ◽  
Ryo Ueno ◽  
Kevin R. Ford ◽  
Christopher A. DiCesare ◽  
Gregory D. Myer ◽  
...  
Keyword(s):  
Shear Force ◽  
Female Athletes ◽  
Vertical Jump ◽  
Musculoskeletal Modeling ◽  
Drop Vertical Jump

scholarly journals 1/2SH

Stroke ◽  
2020 ◽  
Vol 51 (1) ◽  
pp. 193-201 ◽  
Author(s):  
Biao Zhao ◽  
Wan-bing Jia ◽  
Li-ying Zhang ◽  
Ting-zhong Wang
Keyword(s):  
Correlation Coefficient ◽  
Intraclass Correlation Coefficient ◽  
Operating Characteristic ◽  
Small Volume ◽  
Characteristic Curve ◽  
Intraclass Correlation ◽  
Intracerebral Hematoma ◽  
Accuracy Evaluation ◽  
Imaging Data ◽  
3 Dimensional

Background and Purpose— 1/2ABC has been used widely for assessing the volume of intracerebral hematoma. However, it is only suitable for calculating regular and small volume hematomas. Therefore, we re-explored the formula of hematoma volume to find a method that can calculate hematoma volumes accurately, reliably, and quickly. Methods— Computed tomography imaging data of 257 patients with intracerebral hemorrhage were collected. Hematoma volumes were estimated using 3-dimensional Slicer and 7 formulas (π/6ABC, 1/2ABC, 1/3ABC, 2/3SH, 1/2SH, π/6SH, and 2.5/6ABC). Taking the hematoma volumes measured by 3-dimensional Slicer as the reference standard, the accuracy and reliability of the 7 formulas were evaluated. Furthermore, the time needed to calculate hematoma volumes by the 1/2SH method was noted for further analysis. Results— (1) The accuracy of the 7 formulas based on the error analysis from the highest to the lowest was: π/6SH, 1/2SH, 2.5/6ABC, 1/3ABC, 1/2ABC, and π/6ABC or 2/3SH. According to concordance analysis and receiver operating characteristic curve analysis, the results from the highest to lowest were as follows: 1/2SH, π/6SH, 2.5/6ABC, 1/3ABC, 1/2ABC, 2/3SH, and π/6ABC. After categorizing cases according to size, shape, and location of hematoma, the results were almost the same as the results for overall accuracy evaluation in any subgroup. (2) Intraclass correlation coefficient (ICC) of 1/2SH in intra and inter-researcher were 0.998 and 0.989, respectively. For the formula π/6SH, intraclass correlation coefficient was the same as that of 1/2ABC. Kappa values of 1/2SH for intra- and inter-observer were 0.992 and 0.913, respectively. For π/6SH, kappa values of within- and between-reader were 0.984 and 0.904, respectively. (3) The average time taken to calculate hematoma volumes by 1/2SH was 74 seconds. Conclusions— The 1/2SH and π/6SH are accurate, reliable, and rapid methods for calculating hematoma volumes. The accuracy and reliability of 1/2SH were slightly higher than those of π/6SH.

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