Статті в журналах: "Kinematic Registration"

1

Neu, C. P., R. D. McGovern, and J. J. Crisco. "Kinematic Accuracy of Three Surface Registration Methods in a Three-Dimensional Wrist Bone Study." Journal of Biomechanical Engineering 122, no. 5 (April 2, 2000): 528–33. http://dx.doi.org/10.1115/1.1289992.

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The use of registration techniques to determine motion transformations noninvasively has become more widespread with the increased availability of the necessary software. In this study, three surface registration techniques were used to generate carpal bone kinematic results from a single cadaveric wrist specimen. Surface contours were extracted from specimen computed tomography volume images of the forearm, carpal, and metacarpal bones in four arbitrary positions. Kinematic results from each of three registration techniques were compared with results derived from multiple spherical markers fixed to the specimen. Kinematic accuracy was found to depend on the registration method and bone size and shape. In general, rotation errors of the capitate and scaphoid were less than 0.5 deg for all three techniques. Rotation errors for the other bones were generally less than 2 deg, although error for the trapezoid was greater than 2 deg in one technique. Translation errors of the bones were generally less than 1 mm, although errors of the trapezoid and trapezium were greater than 1 mm for two techniques. Tradeoffs existed in each registration method between image processing time and overall kinematic accuracy. Markerless bone registration (MBR) can provide accurate measurements of carpal kinematics and can be used to study the noninvasive, three-dimensional in vivo kinematics of the wrist and other skeletal joints. [S0148-0731(00)01105-5]

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Lin, Cheng-Chung, Hsuan-Lun Lu, Tung-Wu Lu, Chia-Yang Wang, Jia-Da Li, Mei-Ying Kuo, and Horng-Chuang Hsu. "Reconstruction of Three-Dimensional Tibiofemoral Kinematics Using Single-Plane Fluoroscopy and a Personalized Kinematic Model." Applied Sciences 11, no. 20 (October 11, 2021): 9415. http://dx.doi.org/10.3390/app11209415.

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Model-based 3D/2D image registration using single-plane fluoroscopy is a common setup to determine knee joint kinematics, owing to its markerless aspect. However, the approach was subjected to lower accuracies in the determination of out-of-plane motion components. Introducing additional kinematic constraints with an appropriate anatomical representation may help ameliorate the reduced accuracy of single-plane image registration. Therefore, this study aimed to develop and evaluate a multibody model-based tracking (MbMBT) scheme, embedding a personalized kinematic model of the tibiofemoral joint for the measurement of tibiofemoral kinematics. The kinematic model was consisted of three ligaments and an articular contact mechanism. The knee joint activities in six volunteers during isolated knee flexion, lunging, and sit-to-stand motions were recorded with a biplane X-ray imaging system. The tibiofemoral kinematics determined with the MbMBT and mediolateral view fluoroscopic images were compared against those determined using biplane fluoroscopic images. The MbMBT was demonstrated to yield tibiofemoral kinematics with precision values in the range from 0.1 mm to 1.1 mm for translations and from 0.2° to 1.3° for rotations. The constraints provided by the kinematic model were shown to effectively amend the nonphysiological tibiofemoral motion and not compromise the image registration accuracy with the proposed MbMBT scheme.

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3

Eberharter, Johannes K., and Bahram Ravani. "Kinematic Registration in 3D Using the 2D Reuleaux Method." Journal of Mechanical Design 128, no. 2 (July 1, 2005): 349–55. http://dx.doi.org/10.1115/1.2159027.

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This paper presents a method for kinematic registration in three dimensions using a classical technique from two-dimensional kinematics, namely the Reuleaux method. In three dimensions the kinematic registration problem involves reconstruction of a spatial displacement from data on a minimum of three homologous points at two finitely separated positions of a rigid body. When more than the minimum number of homologous points are specified or when errors in specification of these points are considered, the problem becomes an over determined approximation problem. A computational geometric method is presented, resulting in a linear solution of the over determined system. The results have applications in robotics, manufacturing, and biomedical imaging. The paper considers the kinematic registration when minimal, over-determined, infinitesimal, and perturbed sets of homologous point data are given.

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4

Crane, Elizabeth A., Ruth B. Cassidy, Edward D. Rothman, and Geoffrey E. Gerstner. "Effect of registration on cyclical kinematic data." Journal of Biomechanics 43, no. 12 (August 2010): 2444–47. http://dx.doi.org/10.1016/j.jbiomech.2010.04.024.

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5

Biryukova, E. V., A. A. Frolov, I. V. Grinyagin, V. F. Korshunov, S. Yu Romanov, and I. A. Smirnitskaya. "Biomechanical Analysis of Digital Movement in Injured Hand as Method for Functional Diagnosis." N.N. Priorov Journal of Traumatology and Orthopedics 17, no. 2 (June 15, 2010): 70–77. http://dx.doi.org/10.17816/vto201017270-77.

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New method for functional diagnostics of motion activity of fingers based on registration of digital movements and their biomechanical analysis is suggested. Kinematical and dynamical parameters of digital movement accounted by biomechanical model adequately reflect the patterns of motion disorders and give the objective numerical evaluation. The method includes: a) registration of digital movement in both intact and injured hands using electromagnetic system of MiniBirds type; b) calculation of individual biomechanical parameters of fingers - length of phalanges, position and alignment; c) calculation of kinematic parameters of movement - time-base of joint angles, angular velocities and accelerations, range of motion of separate joints, degree of coordination of changes in various joints angles (kinematic synergy); d) evalua-tion of dynamic parameters of motion - time-base of total muscular forces moment in joints (dynamic synergy); e) evaluation of functional state based on analysis of kinematic and dynamic parameters of motion before, during and after treatment.

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6

Beek, Maarten, Carolyn F. Small, Randy E. Ellis, Richard W. Sellens, and David R. Pichora. "Bone Alignment Using the Iterative Closest Point Algorithm." Journal of Applied Biomechanics 26, no. 4 (November 2010): 526–30. http://dx.doi.org/10.1123/jab.26.4.526.

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Computer assisted surgical interventions and research in joint kinematics rely heavily on the accurate registration of three-dimensional bone surface models reconstructed from various imaging technologies. Anomalous results were seen in a kinematic study of carpal bones using a principal axes alignment approach for the registration. The study was repeated using an iterative closest point algorithm, which is more accurate, but also more demanding to apply. The principal axes method showed errors between 0.35 mm and 0.49 mm for the scaphoid, and between 0.40 mm and 1.22 mm for the pisiform. The iterative closest point method produced errors of less than 0.4 mm. These results show that while the principal axes method approached the accuracy of the iterative closest point algorithm in asymmetrical bones, there were more pronounced errors in bones with some symmetry. Principal axes registration for carpal bones should be avoided.

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7

Nederbragt, Walter W., and Bahram Ravani. "Enumeration of Contact Geometries for Kinematic Registration Using Tactile Sensing Fixtures." Journal of Mechanical Design 128, no. 1 (May 5, 2005): 34–45. http://dx.doi.org/10.1115/1.2118731.

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This paper uses group theory for enumeration of contacts between geometric elements necessary for kinematic registration or part referencing in robotics. The results are applied to type synthesis of tactile sensing mechanical fixtures. Kinematic registration is an important step in robot calibration and in data driven automation. Although the scope of the paper is limited to geometric contacts involving points, lines, planar surfaces, cylindrical surfaces, and spherical surfaces, the techniques developed are general and can be applied to other geometric features and non-tactile sensing elements used in robotic calibration and part referencing.

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8

Hinz, Lennart, Markus Kästner, and Eduard Reithmeier. "Metal Forming Tool Monitoring Based on a 3D Measuring Endoscope Using CAD Assisted Registration." Sensors 19, no. 9 (May 5, 2019): 2084. http://dx.doi.org/10.3390/s19092084.

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In order to provide timely, reliable, and comprehensive data for the maintenance of highly stressed geometries in sheet-bulk metal forming tools, this article features a possible setup by combining a 3D measuring endoscope with a two-stage kinematic. The measurement principle is based on the projection of structured light, allowing time-effective measurements of larger areas. To obtain data of proper quality, several hundred measurements are performed which then have to be registered and finally merged into one single point cloud. Factors such as heavy, unwieldy specimens affecting precise alignment. The rotational axes are therefore possibly misaligned and the kinematics and the hand-eye transformation remain uncalibrated. By the use of computer-aided design (CAD) data, registration can be improved, allowing a detailed examination of local features like gear geometries while reducing the sensitivity to detect shape deviations.

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9

Lopomo, Nicola, Francesca Colle, Cecilia Signorelli, Marco Bontempi, Matteo Baracchi, and Andrea Visani. "ONE-STEP FUNCTIONAL REGISTRATION FOR KINEMATIC ANALYSIS IN COMPUTER AIDED SURGERY." Journal of Biomechanics 45 (July 2012): S65. http://dx.doi.org/10.1016/s0021-9290(12)70066-0.

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10

Wieckiewicz, Mieszko, Marek Zietek, Danuta Nowakowska, and Wlodzimierz Wieckiewicz. "Comparison of Selected Kinematic Facebows Applied to Mandibular Tracing." BioMed Research International 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/818694.

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The study focused on the comparison between mechanical and computerized registration methods used by the two selected kinematic facebows. The material consisted of 35 women aged 18 to 35, studied using the Gerber Dynamic Facebow and the computerized ARCUSdigma II axiograph. To compare the devices the condylar path inclination (CPI) was recorded according to the Camper’s line, enabling the acquisition of easily comparable values based on which the devices were objectively and subjectively analyzed. Statistics was performed for the obtained data. The study showed that the values for the CPI registrated by the ARCUSdigma II are significantly higher than those obtained by using the Gerber Dynamic Facebow. The significant difference in the records of the CPI is most likely a result of the differences in the registration techniques assumptions. ARCUSdigma II provides the user with more diagnostic options than Gerber Dynamic Facebow. Mechanical facebow handling has a higher risk of hand-measuring errors in tracing procedure. Due to high discrepancy of achieved results from different systems the authors recommend to use articulator compatible with facebow whose measurement has been done.

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11

Zhang, S., D. D. Lichti, J. C. Küpper, and J. L. Ronsky. "AN AUTOMATIC ICP-BASED 2D-3D REGISTRATION METHOD FOR A HIGH-SPEED BIPLANAR VIDEORADIOGRAPHY IMAGING SYSTEM." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B2-2020 (August 12, 2020): 805–12. http://dx.doi.org/10.5194/isprs-archives-xliii-b2-2020-805-2020.

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Abstract. High-Speed Biplanar Videoradiography (HSBV) is an X-ray based non-invasive imaging system that can be used to derive dynamic bony translations and rotations. The 2D-3D registration process matches a 3D bone model acquired from magnetic resonance imaging (MRI) or computed tomography (CT) scans with the 2D X-ray image pairs. This study focuses on the registration of MRI data as it can acquire detailed soft tissue contrast that cannot be easily discerned in CT scans. A novel 2D-3D registration method is reported in this paper that is suitable for the MRI-based bone models with high precision and high efficiency. In addition, an automatic initialization procedure with 64 starting poses is established to avoid user intervention in the registration. The method has been tested using the HSBV image sequence of a knee joint during walking. Thirty-five consecutive poses from the sequence were tested for the registration, and 50 non-consecutive poses randomly selected from the sequence were tested for the automatic initialization. The registration precision for each axis was 0.49 to 0.54 mm. For the initialization validation test, 48 over 50 frames were successfully initialized and two failed due to portions of the joint falling outside of the field-of-view of the system. The average time for each initialization is only about 6 min. The improved 2D-3D registration will allow determination of precise 3D kinematic parameters with high efficiency. These kinematic parameters can be used to calculate joint cartilage contact mechanics that provide insight into the mechanical processes and mechanisms of joint degeneration or pathology.

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12

Higashi, Ryosuke, Toshihiro Sera, Hisashi Naito, Takeshi Matsumoto, and Masao Tanaka. "Pulmonary kinematic analysis with non-rigid deformable registration for detecting localised emphysema." Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization 5, no. 2 (March 23, 2015): 100–109. http://dx.doi.org/10.1080/21681163.2015.1008649.

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13

Fischer, K. J., T. T. Manson, H. J. Pfaeffle, M. M. Tomaino, and S. L. Y. Woo. "A method for measuring joint kinematics designed for accurate registration of kinematic data to models constructed from CT data." Journal of Biomechanics 34, no. 3 (March 2001): 377–83. http://dx.doi.org/10.1016/s0021-9290(00)00195-0.

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14

Lucero, Jorge C., Kevin G. Munhall, Vincent L. Gracco, and James O. Ramsay. "On the Registration of Time and the Patterning of Speech Movements." Journal of Speech, Language, and Hearing Research 40, no. 5 (October 1997): 1111–17. http://dx.doi.org/10.1044/jslhr.4005.1111.

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In order to study speech coordination we frequently average kinematic and other physiological signals. The averages are assumed to be more representative of the underlying patterns of production than individual records. In this note we outline different approaches to averaging and present a new nonlinear normalization technique that offers better information than ensemble averaging, linear normalization, or feature alignment methods. We suggest that this technique provides a clear estimation of pattern shape while preserving information on the variation over time.

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15

López Isaza, Julián Andrés, Mario Andrés Cuéllar Cárdenas, Lina María Cetina Tarazona, Anny Julieth Forero Ortega, Ana Milena Suárez Arias, Oscar Freddy Muñoz Rodríguez, Luis Miguel Aguirre Hoyos, and María Juliana Gutiérrez López. "Graphical representation of structural data in the field: A methodological proposal for application in deformed areas." Boletín Geológico 48, no. 1 (July 12, 2021): 123–39. http://dx.doi.org/10.32685/0120-1425/bol.geol.48.1.2021.504.

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The description of the fabric elements represented by the linear and planar structures present at different scales is a key component of fieldwork. A scheme is proposed for the systematic registration of planes and lineations, coded as S (planar surfaces), F (folds), and L (lineations), among others, that allows for the orderly storage of the measurements taken. This scheme includes information related to the kinematics, the kinematic indicators, and the certainty or reliability ascribed to the assigned movement. In the fieldwork, the graphic representation of the structural measures in modified projection nets includes concentric circles for each dip. Direct drawing of the outcrop data is undertaken, dispensing with the use of tracing or transparent paper. The stereograms resulting from the graphic representation in the modified Wulff stereographic projection net, and the modified Schmidt equal-area net, can be complemented by rose diagrams for visualization of the spatial ordering. During field campaigns in the outcrops, it is essential to visualize the spatial orientation of the data in the diagrams to determine the main structural trends, the vergence, the kinematic nature of faults and shear zones, paleo-stress tensors, and to differentiate structural domains, among others. This information supports the reconstruction of geological and tectonic history and the establishment of relationships between the different geological processes.

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16

Ardestani, Marzieh M., Christopher E. Henderson, Gordhan Mahtani, Mark Connolly, and T. George Hornby. "Locomotor Kinematics and Kinetics Following High-Intensity Stepping Training in Variable Contexts Poststroke." Neurorehabilitation and Neural Repair 34, no. 7 (June 6, 2020): 652–60. http://dx.doi.org/10.1177/1545968320929675.

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Background and Purpose. Previous studies suggest that individuals poststroke can achieve substantial gains in walking function following high-intensity locomotor training (LT). Recent findings also indicate practice of variable stepping tasks targeting locomotor deficits can mitigate selected impairments underlying reduced walking speeds. The goal of this study was to investigate alterations in locomotor biomechanics following 3 different LT paradigms. Methods. This secondary analysis of a randomized trial recruited individuals 18 to 85 years old and >6 months poststroke. We compared changes in spatiotemporal, joint kinematics, and kinetics following up to 30 sessions of high-intensity (>70% heart rate reserve [HRR]) LT of variable tasks targeting paretic limb and balance impairments (high-variable, HV), high-intensity LT focused only on forward walking (high-forward, HF), or low-intensity LT (<40% HRR) of variable tasks (low-variable, LV). Sagittal spatiotemporal and joint kinematics, and concentric joint powers were compared between groups. Regressions and principal component analyses were conducted to evaluate relative contributions or importance of biomechanical changes to between and within groups. Results. Biomechanical data were available on 50 participants who could walk ≥0.1 m/s on a motorized treadmill. Significant differences in spatiotemporal parameters, kinematic consistency, and kinetics were observed between HV and HF versus LV. Resultant principal component analyses were characterized by paretic powers and kinematic consistency following HV, while HF and LV were characterized by nonparetic powers. Conclusion. High-intensity LT results in greater changes in kinematics and kinetics as compared with lower-intensity interventions. The results may suggest greater paretic-limb contributions with high-intensity variable stepping training that targets specific biomechanical deficits. Clinical Trial Registration. https://clinicaltrials.gov/ Unique Identifier: NCT02507466

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Brun, Aurélien, Davide A. Cucci, and Jan Skaloud. "Lidar point–to–point correspondences for rigorous registration of kinematic scanning in dynamic networks." ISPRS Journal of Photogrammetry and Remote Sensing 189 (July 2022): 185–200. http://dx.doi.org/10.1016/j.isprsjprs.2022.04.027.

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Trinidad-Fernández, Manuel, David Beckwée, Antonio Cuesta-Vargas, Manuel González-Sánchez, Francisco-Angel Moreno, Javier González-Jiménez, Erika Joos, and Peter Vaes. "Validation, Reliability, and Responsiveness Outcomes of Kinematic Assessment with an RGB-D Camera to Analyze Movement in Subacute and Chronic Low Back Pain." Sensors 20, no. 3 (January 27, 2020): 689. http://dx.doi.org/10.3390/s20030689.

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Background: The RGB-D camera is an alternative to asses kinematics in order to obtain objective measurements of functional limitations. The aim of this study is to analyze the validity, reliability, and responsiveness of the motion capture depth camera in sub-acute and chronic low back pain patients. Methods: Thirty subjects (18–65 years) with non-specific lumbar pain were screened 6 weeks following an episode. RGB-D camera measurements were compared with an inertial measurement unit. Functional tests included climbing stairs, bending, reaching sock, lie-to-sit, sit-to-stand, and timed up-and-go. Subjects performed the maximum number of repetitions during 30 s. Validity was analyzed using Spearman’s correlation, reliability of repetitions was calculated by the intraclass correlation coefficient and the standard error of measurement, and receiver operating characteristic curves were calculated to assess the responsiveness. Results: The kinematic analysis obtained variable results according to the test. The time variable had good values in the validity and reliability of all tests (r = 0.93–1.00, (intraclass correlation coefficient (ICC) = 0.62–0.93). Regarding kinematics, the best results were obtained in bending test, sock test, and sit-to-stand test (r = 0.53–0.80, ICC = 0.64–0.83, area under the curve (AUC) = 0.55–84). Conclusion: Functional tasks, such as bending, sit-to-stand, reaching, and putting on sock, assessed with the RGB-D camera, revealed acceptable validity, reliability, and responsiveness in the assessment of patients with low back pain (LBP). Trial registration: ClinicalTrials.gov NCT03293095 “Functional Task Kinematic in Musculoskeletal Pathology” 26 September 2017

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19

Franaszek, Marek, and Jeremy A. Marvel. "Using Full Pose Measurement for Serial Robot Calibration." Applied Sciences 12, no. 7 (April 6, 2022): 3680. http://dx.doi.org/10.3390/app12073680.

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To ensure smooth robot operations, parameters of its kinematic model and a registration transformation between robot base and world coordinate frame must be determined. Both tasks require data acquired by external sensors that can measure either 3D locations or full 6D poses. We show that use of full pose measurements leads to much smaller robot orientation errors when compared with the outcome of calibration and registration procedures based on 3D data only. Robot position errors are comparable for both types of data. The conclusion is based on extensive simulations of 7 degrees of freedom robot arm and different levels of pseudo-noise perturbing both positional and rotational components of pose.

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20

Ikebe, Satoru, Yifeng Wang, Hidehiko Higaki, Yoshitaka Shiraishi, Takeshi Shimoto, Yoshitaka Nakanishi, Daisuke Hara, Satoshi Hamai, Yasuharu Nakashima, and Yukihide Iwamoto. "PS4-19 Kinematic analysis of hip joints in twisting by the 2D-3D registration technique(PS4: Poster Short Presentation IV,Poster Session)." Proceedings of the Asian Pacific Conference on Biomechanics : emerging science and technology in biomechanics 2015.8 (2015): 297. http://dx.doi.org/10.1299/jsmeapbio.2015.8.297.

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21

Matrosova, Y. V., M. G. Kataev, and O. L. Fabrikantov. "Diplography – a new method for studying of binocular diplopia." Reflection, no. 1 (June 7, 2022): 69–72. http://dx.doi.org/10.25276/2686-6986-2022-1-69-72.

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The article describes a new method for studying diplopia – diplography. The essence of the method is the assessment and determination of the qualitative characteristics of diplopia, based on the registration of a change in the position of the virtual image when the direction of gaze and head position of a patient with strabismus change. Key words: diplopia; strabismus; extraocular muscles; computer program; kinematic diplography.

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Ferrández-Laliena, Loreto, Lucía Vicente-Pina, Rocío Sánchez-Rodríguez, Eva Orantes-González, José Heredia-Jimenez, María Orosia Lucha-López, César Hidalgo-García, and José Miguel Tricás-Moreno. "Diagnostics Using the Change-of-Direction and Acceleration Test (CODAT) of the Biomechanical Patterns Associated with Knee Injury in Female Futsal Players: A Cross-Sectional Analytical Study." Diagnostics 13, no. 5 (March 1, 2023): 928. http://dx.doi.org/10.3390/diagnostics13050928.

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The primary aim of this study was to identify kinematic differences at initial contact between female futsal players with and without previous knee injury, using a functional motor pattern test. The secondary aim was to determine kinematic differences between the dominant and non-dominant limb in the whole group, using the same test. A cross-sectional study was performed in 16 female futsal players allocated into two groups: eight females with a previous knee injury, i.e., affected by the valgus collapse mechanism without surgical intervention, and eight with no previous injury. The evaluation protocol included the change-of-direction and acceleration test (CODAT). One registration was made for each lower limb, i.e., the dominant (the preferred kicking limb) and non-dominant limb. A 3D motion capture system (Qualisys AB, Göteborg, Sweden) was used to analyze the kinematics. The Cohen’s d effect sizes between the groups demonstrated a strong effect size towards more physiological positions in the non-injured group in the following kinematics in the dominant limb: hip adduction (Cohen’s d = 0.82), hip internal rotation (Cohen’s d = 0.88), and ipsilateral pelvis rotation (Cohen’s d = 1.06). The t-test for the dominant and non-dominant limb in the whole group showed the following differences in knee valgus: dominant limb (9.02 ± 7.31 degrees) and non-dominant limb (1.27 ± 9.05 degrees) (p = 0.049). Conclusions: The players with no previous history of knee injury had a more physiological position for avoiding the valgus collapse mechanism in the hip adduction and internal rotation, and in the pelvis rotation in the dominant limb. All the players showed more knee valgus in the dominant limb, which is the limb at greater risk of injury.

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Kono, K., T. Tomita, K. Futai, T. Yamazaki, S. Tanaka, H. Yoshikawa, and K. Sugamoto. "In vivo three-dimensional kinematics of normal knees during different high-flexion activities." Bone & Joint Journal 100-B, no. 1 (January 2018): 50–55. http://dx.doi.org/10.1302/0301-620x.100b1.bjj-2017-0553.r2.

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Aims In Asia and the Middle-East, people often flex their knees deeply in order to perform activities of daily living. The purpose of this study was to investigate the 3D kinematics of normal knees during high-flexion activities. Our hypothesis was that the femorotibial rotation, varus-valgus angle, translations, and kinematic pathway of normal knees during high-flexion activities, varied according to activity. Materials and Methods We investigated the in vivo kinematics of eight normal knees in four male volunteers (mean age 41.8 years; 37 to 53) using 2D and 3D registration technique, and modelled the knees with a computer aided design program. Each subject squatted, kneeled, and sat cross-legged. We evaluated the femoral rotation and varus-valgus angle relative to the tibia and anteroposterior translation of the medial and lateral side, using the transepicodylar axis as our femoral reference relative to the perpendicular projection on to the tibial plateau. This method evaluates the femur medially from what has elsewhere been described as the extension facet centre, and differs from the method classically applied. Results During squatting and kneeling, the knees displayed femoral external rotation. When sitting cross-legged, femurs displayed internal rotation from 10° to 100°. From 100°, femoral external rotation was observed. No significant difference in varus-valgus angle was seen between squatting and kneeling, whereas a varus position was observed from 140° when sitting cross-legged. The measure kinematic pathway using our methodology found during squatting a medial pivoting pattern from 0° to 40° and bicondylar rollback from 40° to 150°. During kneeling, a medial pivot pattern was evident. When sitting cross-legged, a lateral pivot pattern was seen from 0° to 100°, and a medial pivot pattern beyond 100°. Conclusion The kinematics of normal knees during high flexion are variable according to activity. Nevertheless, our study was limited to a small number of male patients using a different technique to report the kinematics than previous publications. Accordingly, caution should be observed in generalizing our findings. Cite this article: Bone Joint J 2018;100-B:50–5.

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24

Baroon, Jasem, and Bahram Ravani. "A Computational Geometric Solution of the Kinematic Registration Problem Using the Bisecting Linear Line Complex." Computer-Aided Design and Applications 6, no. 1 (January 2009): 1–13. http://dx.doi.org/10.3722/cadaps.2009.1-13.

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25

Cunningham, Bryan W., and Daina M. Brooks. "Comparative Analysis of Optoelectronic Accuracy in the Laboratory Setting Versus Clinical Operative Environment: A Systematic Review." Global Spine Journal 12, no. 2_suppl (April 2022): 59S—74S. http://dx.doi.org/10.1177/21925682211035083.

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Study Design: Systematic review. Objectives: The optoelectronic camera source and data interpolation process serve as the foundation for navigational integrity in robotic-assisted surgical platforms. The current systematic review serves to provide a basis for the numerical disparity observed when comparing the intrinsic accuracy of optoelectronic cameras versus accuracy in the laboratory setting and clinical operative environments. Methods: Review of the PubMed and Cochrane Library research databases was performed. The exhaustive literature compilation obtained was then vetted to reduce redundancies and categorized into topics of intrinsic accuracy, registration accuracy, musculoskeletal kinematic platforms, and clinical operative platforms. Results: A total of 465 references were vetted and 137 comprise the basis for the current analysis. Regardless of application, the common denominators affecting overall optoelectronic accuracy are intrinsic accuracy, registration accuracy, and application accuracy. Intrinsic accuracy equaled or was less than 0.1 mm translation and 0.1 degrees rotation per fiducial. Controlled laboratory platforms reported 0.1 to 0.5 mm translation and 0.1 to 1.0 degrees rotation per array. Accuracy in robotic-assisted spinal surgery reported 1.5 to 6.0 mm translation and 1.5 to 5.0 degrees rotation when comparing planned to final implant position. Conclusions: Navigational integrity and maintenance of fidelity of optoelectronic data is the cornerstone of robotic-assisted spinal surgery. Transitioning from controlled laboratory to clinical operative environments requires an increased number of steps in the optoelectronic kinematic chain and error potential. Diligence in planning, fiducial positioning, system registration and intra-operative workflow have the potential to improve accuracy and decrease disparity between planned and final implant position.

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Barrance, Peter J., Glenn N. Williams, John E. Novotny, and Thomas S. Buchanan. "A Method for Measurement of Joint Kinematics in Vivo by Registration of 3-D Geometric Models With Cine Phase Contrast Magnetic Resonance Imaging Data." Journal of Biomechanical Engineering 127, no. 5 (May 31, 2005): 829–37. http://dx.doi.org/10.1115/1.1992524.

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A new method is presented for measuring joint kinematics by optimally matching modeled trajectories of geometric surface models of bones with cine phase contrast (cine-PC) magnetic resonance imaging data. The incorporation of the geometric bone models (GBMs) allows computation of kinematics based on coordinate systems placed relative to full 3-D anatomy, as well as quantification of changes in articular contact locations and relative velocities during dynamic motion. These capabilities are additional to those of cine-PC based techniques that have been used previously to measure joint kinematics during activity. Cine-PC magnitude and velocity data are collected on a fixed image plane prescribed through a repetitively moved skeletal joint. The intersection of each GBM with a simulated image plane is calculated as the model moves along a computed trajectory, and cine-PC velocity data are sampled from the regions of the velocity images within the area of this intersection. From the sampled velocity data, the instantaneous linear and angular velocities of a coordinate system fixed to the GBM are estimated, and integration of the linear and angular velocities is used to predict updated trajectories. A moving validation phantom that produces motions and velocity data similar to those observed in an experiment on human knee kinematics was designed. This phantom was used to assess cine-PC rigid body tracking performance by comparing the kinematics of the phantom measured by this method to similar measurements made using a magnetic tracking system. Average differences between the two methods were measured as 2.82 mm rms for anterior∕posterior tibial position, and 2.63 deg rms for axial rotation. An inter-trial repeatability study of human knee kinematics using the new method produced rms differences in anterior∕posterior tibial position and axial rotation of 1.44 mm and 2.35 deg. The performance of the method is concluded to be sufficient for the effective study of kinematic changes caused to knees by soft tissue injuries.

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Hara, Daisuke, Yasuharu Nakashima, Satoshi Hamai, Hidehiko Higaki, Satoru Ikebe, Takeshi Shimoto, Masanobu Hirata, Masayuki Kanazawa, Yusuke Kohno, and Yukihide Iwamoto. "Kinematic Analysis of Healthy Hips during Weight-Bearing Activities by 3D-to-2D Model-to-Image Registration Technique." BioMed Research International 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/457573.

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Dynamic hip kinematics during weight-bearing activities were analyzed for six healthy subjects. Continuous X-ray images of gait, chair-rising, squatting, and twisting were taken using a flat panel X-ray detector. Digitally reconstructed radiographic images were used for 3D-to-2D model-to-image registration technique. The root-mean-square errors associated with tracking the pelvis and femur were less than 0.3 mm and 0.3° for translations and rotations. For gait, chair-rising, and squatting, the maximum hip flexion angles averaged 29.6°, 81.3°, and 102.4°, respectively. The pelvis was tilted anteriorly around 4.4° on average during full gait cycle. For chair-rising and squatting, the maximum absolute value of anterior/posterior pelvic tilt averaged 12.4°/11.7° and 10.7°/10.8°, respectively. Hip flexion peaked on the way of movement due to further anterior pelvic tilt during both chair-rising and squatting. For twisting, the maximum absolute value of hip internal/external rotation averaged 29.2°/30.7°. This study revealed activity dependent kinematics of healthy hip joints with coordinated pelvic and femoral dynamic movements. Kinematics’ data during activities of daily living may provide important insight as to the evaluating kinematics of pathological and reconstructed hips.

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Chen Wang, M. D., Xiang Geng, Shaobai Wang, M. D. Xin Ma, M. D. Xu Wang, M. D. Jiazhang Huang, M. D. Chao Zhang, M. S. Li Chen, Junsheng Yang, and Kan Wang. "In vivo kinematic study of the tarsal joints complex based on fluoroscopic 3D-2D registration technique." Gait & Posture 49 (September 2016): 54–60. http://dx.doi.org/10.1016/j.gaitpost.2016.06.009.

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Squires, Alexander D., Yabiao Gao, Sean F. Taylor, Marc Kent, and Zion Tsz Ho Tse. "A Simple and Inexpensive Stereotactic Guidance Frame for MRI-Guided Brain Biopsy in Canines." Journal of Medical Engineering 2014 (May 18, 2014): 1–7. http://dx.doi.org/10.1155/2014/139535.

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A magnetic resonance imaging (MRI) guided stereotactic system was developed to provide veterinarians a method to accomplish minimally invasive stereotactic brain biopsies and procedures involving the cerebrum in canines. While MR-guided procedures are prevalent for humans, they are less common in animal practices. The system was designed to minimize fabrication costs in an effort to make such procedures more accessible in the veterinary field. A frame constrained the head without the need for punctures and supported registration and guidance attachments. Location data for registration and relevant structures were selected by the clinician, and a reverse kinematic analysis program generated the settings of the stereotactic arch to guide a needle to the desired location. Phantom experiments and three cadaver trials showed an average targeting error of <3 mm using the system.

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NAP, Mircea Emil, Petre Iuliu DRAGOMIR, Tudor SĂLĂGEAN, Ioana Delia POP, Florica MATEI, Iulia COROIAN, Jutka DEAK, Silvia CHIOREAN, Elemer Emanuel ȘUBA, and Ioan LUPUȚ. "Registration in the Land Book of a River Section." Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Horticulture 78, no. 1 (May 14, 2021): 83. http://dx.doi.org/10.15835/buasvmcn-hort:2020.0065.

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The minor riverbed of the Someș River is identified in the built-up area and the outside of the built-up area of Fărcașa ATU and the Ardusat ATU outside the built-up area, from the Ardusat DJ 193 road bridge, between hm 2725-2855 and between hm 2815-2867, according to GD (Government Decision) 1705/2006. For the first registration work of the Someș minor riverbed, the measurements, their processing and the afferent documentation were made in accordance with the Order of the general director of the National Agency for Cadastre and Real Estate Advertising no. 700/2014, updated in 2020. The purpose of the project refers to the topo-cadastral methods performed for the elaboration of the documentation of first registration in the Land Book of the minor riverbed belonging to the Someș river located within the radius of ATU Ardusat and ATU Fărcașa from Maramureș county. For the acquisition of the necessary data, both field works and office operations for data processing were taken into account, the studied area being 222.7 hectares. Measurements were performed using GNSS technology using the real-time kinematic RTK method. The UAV aerial photogrammetric method was used to obtain a high degree of detail. The drone used was equipped with an RTK module that receives real-time corrections, thus maintaining a high accuracy.

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Teseo Mainieri, Ézio. "Estudo do movimento de Bennett." Revista da Faculdade de Odontologia de Porto Alegre 25, no. 1 (October 17, 2021): 23–31. http://dx.doi.org/10.22456/2177-0018.117945.

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Forty patients, twenty female and twenty male were selected, from a individual group. All the selected patients had twenty six teeth or more. lndividual alginate impressions were takenin the upper and lower arches. After each individual impression had taken, an índividual hinge axis procedure was effectived with a kinematic face bow. Determined the hínge axis each patient was tatued and a arbitrary face - bow was used to mount the upper cast in the gnathothesíometer. The lower cast was related to upper cast throught a centric relation registration (individual). Mounted both casts (upper and lower) in the instrument, two laterals bite registration were taken (one rigth, one left) on the patient and transfered to the gnatho-thesíometer for measurements. The results showed that Bennett moviment, occurred in 1,5 mm average and thus was related to an intimate occlusal scheme for each patient.

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Kotsifaki, Argyro, Vasileios Korakakis, Rod Whiteley, Sam Van Rossom, and Ilse Jonkers. "Measuring only hop distance during single leg hop testing is insufficient to detect deficits in knee function after ACL reconstruction: a systematic review and meta-analysis." British Journal of Sports Medicine 54, no. 3 (May 29, 2019): 139–53. http://dx.doi.org/10.1136/bjsports-2018-099918.

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ObjectiveTo systematically review the biomechanical deficits after ACL reconstruction (ACLR) during single leg hop for distance (SLHD) testing and report these differences compared with the contralateral leg and with healthy controls.DesignSystematic review with meta-analysis.Data sourcesA systematic search in Pubmed (Ovid), EMBASE, CINAHL, Scopus, Web of Science, PEDro, SPORTDiscus, Cochrane Library, grey literature and trial registries, was conducted from inception to 1 April 2018.Eligibility criteria for selecting studiesStudies reporting kinematic, kinetic and/or electromyographic data of the ACLR limb during SLHD with no language limits.ResultsThe literature review yielded 1551 articles and 19 studies met the inclusion criteria. Meta-analysis revealed strong evidence of lower peak knee flexion angle and knee flexion moments during landing compared with the uninjured leg and with controls. Also, moderate evidence (with large effect size) of lower knee power absorption during landing compared with the uninjured leg. No difference was found in peak vertical ground reaction force during landing. Subgroup analyses revealed that some kinematic variables do not restore with time and may even worsen.ConclusionDuring SLHD several kinematic and kinetic deficits were detected between limbs after ACLR, despite adequate SLHD performance. Measuring only hop distance, even using the healthy leg as a reference, is insufficient to fully assess knee function after ACLR.PROSPERO trial registration number CRD42018087779.

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Ren, Xiang, Min Sun, Cheng Jiang, Lei Liu, and Wei Huang. "An Augmented Reality Geo-Registration Method for Ground Target Localization from a Low-Cost UAV Platform." Sensors 18, no. 11 (November 2, 2018): 3739. http://dx.doi.org/10.3390/s18113739.

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This paper presents an augmented reality-based method for geo-registering videos from low-cost multi-rotor Unmanned Aerial Vehicles (UAVs). The goal of the proposed method is to conduct an accurate geo-registration and target localization on a UAV video stream. The geo-registration of video stream requires accurate attitude data. However, the Inertial Measurement Unit (IMU) sensors on most low-cost UAVs are not capable of being directly used for geo-registering the video. The magnetic compasses on UAVs are more vulnerable to the interferences in the working environment than the accelerometers. Thus the camera yaw error is the main sources of the registration error. In this research, to enhance the low accuracy attitude data from the onboard IMU, an extended Kalman Filter (EKF) model is used to merge Real Time Kinematic Global Positioning System (RTK GPS) data with the IMU data. In the merge process, the high accuracy RTK GPS data can be used to promote the accuracy and stability of the 3-axis body attitude data. A method of target localization based on the geo-registration model is proposed to determine the coordinates of the ground targets in the video. The proposed method uses a modified extended Kalman Filter to combine the data from RTK GPS and the IMU to improve the accuracy of the geo-registration and the localization result of the ground targets. The localization results are compared to the reference point coordinates from satellite image. The comparison indicates that the proposed method can provide practical geo-registration and target localization results.

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Ren, Xiang, Min Sun, Xianfeng Zhang, Lei Liu, Xiuyuan Wang, and Hang Zhou. "An AR Geo-Registration Algorithm for UAV TIR Video Streams Based on Dual-Antenna RTK-GPS." Remote Sensing 14, no. 9 (May 5, 2022): 2205. http://dx.doi.org/10.3390/rs14092205.

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In emergency response and disaster rescue, unmanned aerial vehicles (UAVs) onboard thermal infrared (TIR) sensors are an essential means of acquiring ground information in the nighttime working environment. To enable field personnel to make better decisions based on TIR video streams returned from a UAV, the geographic information enhancement of TIR video streams is required. At present, it is difficult for low-cost UAVs to carry high-precision attitude sensors and thus obtain high-precision camera attitude information to meet the enhanced processing requirements of UAV TIR video streams. To this end, this paper proposes an improved Kalman filter algorithm to improve the geographic registration (geo-registration) accuracy by fusing the positioning and heading data from the dual-antenna real-time kinematic global positioning system (RTK-GPS) with onboard internal measurement unit (IMU) data. This method can yield high-precision position and attitude data in real time based on low-cost UAV hardware, based on which high-precision geo-registration results can be obtained. The computational complexity can be reduced compared with video stream feature tracking algorithms. Furthermore, the problem of unstable matching due to the low resolution and texture level of TIR video streams can be avoided. The experimental results prove that the proposed method can reduce the registration error by 66.15%, and significantly improve the geo-registration accuracy of UAV TIR video streams. Thus, it can strongly support the popularization and practicality of the application of augmented reality (AR) technology to low-cost UAV platforms.

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Fassina, Lorenzo, Marisa Cornacchione, Manuela Pellegrini, Maria Evelina Mognaschi, Roberto Gimmelli, Andrea Maria Isidori, Andrea Lenzi, Giovanni Magenes та Fabio Naro. "Model of Murine Ventricular Cardiac Tissue for In Vitro Kinematic-Dynamic Studies of Electromagnetic and β-Adrenergic Stimulation". Journal of Healthcare Engineering 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/4204085.

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In a model of murine ventricular cardiac tissue in vitro, we have studied the inotropic effects of electromagnetic stimulation (frequency, 75 Hz), isoproterenol administration (10 μM), and their combination. In particular, we have performed an image processing analysis to evaluate the kinematics and the dynamics of beating cardiac syncytia starting from the video registration of their contraction movement. We have found that the electromagnetic stimulation is able to counteract the β-adrenergic effect of isoproterenol and to elicit an antihypertrophic response.

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Strickland, Catherine G., Daniel E. Aguiar, Eric A. Nauman, and Thomas M. Talavage. "Development of Subject-Specific Geometric Spine Model through Use of Automated Active Contour Segmentation and Kinematic Constraint-Limited Registration." Journal of Digital Imaging 24, no. 5 (September 30, 2010): 926–42. http://dx.doi.org/10.1007/s10278-010-9336-z.

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Nagamoto, Yukitaka, Motoki Iwasaki, Hironobu Sakaura, Tsuyoshi Sugiura, Takahito Fujimori, Yohei Matsuo, Masafumi Kashii, Tsuyoshi Murase, Hideki Yoshikawa, and Kazuomi Sugamoto. "Sacroiliac joint motion in patients with degenerative lumbar spine disorders." Journal of Neurosurgery: Spine 23, no. 2 (August 2015): 209–16. http://dx.doi.org/10.3171/2014.12.spine14590.

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OBJECT Usually additional anchors into the ilium are necessary in long fusion to the sacrum for degenerative lumbar spine disorders (DLSDs), especially for adult spine deformity. Although the use of anchors is becoming quite common, surgeons must always keep in mind that the sacroiliac (SI) joint is mobile and they should be aware of the kinematic properties of the SI joint in patients with DLSDs, including adult spinal deformity. No previous study has clarified in vivo kinematic changes in the SI joint with respect to patient age, sex, or parturition status or the presence of DLSDs. The authors conducted a study to clarify the mobility and kinematic characteristics of the SI joint in patients with DLSDs in comparison with healthy volunteers by using in vivo 3D motion analysis with voxel-based registration, a highly accurate, noninvasive method. METHODS Thirteen healthy volunteers (the control group) and 20 patients with DLSDs (the DLSD group) underwent low-dose 3D CT of the lumbar spine and pelvis in 3 positions (neutral, maximal trunk flexion, and maximal trunk extension). SI joint motion was calculated by computer processing of the CT images (voxel-based registration). 3D motion of the SI joint was expressed as both 6 df by Euler angles and translations on the coordinate system and a helical axis of rotation. The correlation between joint motion and the cross-sectional area of the trunk muscles was also investigated. RESULTS SI joint motion during trunk flexion-extension was minute in healthy volunteers. The mean rotation angles during trunk flexion were 0.07° around the x axis, −0.02° around the y axis, and 0.16° around the z axis. The mean rotation angles during trunk extension were 0.38° around the x axis, −0.08° around the y axis, and 0.08° around the z axis. During trunk flexion-extension, the largest amount of motion occurred around the x axis. In patients with DLSDs, the mean rotation angles during trunk flexion were 0.57° around the x axis, 0.01° around the y axis, and 0.19° around the z axis. The mean rotation angles during trunk extension were 0.68° around the x axis, −0.11° around the y axis, and 0.05° around the z axis. Joint motion in patients with DLSDs was significantly greater, with greater individual difference, than in healthy volunteers. Among patients with DLSDs, women had significantly more motion than men did during trunk extension. SI joint motion was significantly negatively correlated with the cross-sectional area of the trunk muscles during both flexion and extension of the trunk. CONCLUSIONS The authors elucidated the mobility and kinematic characteristics of the SI joint in patients with DLSDs compared with healthy volunteers for the first time. This information is useful for spine surgeons because of the recent increase in spinopelvic fusion for the treatment of DLSDs.

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Kotukh, Volodimir, Nataliy Kaptsova, Yuriy Pakhomov, and Vitaliy Kosenko. "Information model of registration and analysis of technological factors arising during final processing of products of transport pipeline systems." International Journal of Engineering & Technology 7, no. 2.23 (April 20, 2018): 73. http://dx.doi.org/10.14419/ijet.v7i2.23.11887.

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One of the most important technological characteristics of the rubbing surfaces of the shut-off part of the pipe fittings (PF) of the transport pipeline systems (TPS) is their waviness, which is characterized by the deviation of the step of the wave to the height of the micro-roughness. The nature of the waviness is associated with oscillations of the working bodies of the executive devices of the technological equipment in the production process of manufacturing or repairing precision pairs of PF. The waviness of the rubbing surfaces of the PF shut-off part, as well as the high accuracy of their processing, is achieved by increasing the kinematic stiffness of the process equipment, as well as improving the methods and means for the precise processing of the PF precision pairs.

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Firsov, A. A., A. V. Efimov, N. S. Kolosov, I. A. Moralev, and S. B. Leonov. "Intensification of mixing of fuel with supersonic air flow when injection and electric discharge are combined." Journal of Physics: Conference Series 2100, no. 1 (November 1, 2021): 012007. http://dx.doi.org/10.1088/1742-6596/2100/1/012007.

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Abstract This paper presents the results of experimental investigations of DC discharge influence on mixing intensification of transvers injected gas jet into supersonic aiflow. The air was used as injected gas to prevent the influence of chemical reactions on measurements. The data obtained during discharge includes current and voltage acquisition, registration of pressure pulsations in the jet downstream of discharge operation accompanied by correlation and Fourier analysis allowed to conclude that discharge significantly increase the pressure pulsations in a wide frequency range of 1000 Hz to 50kHz. Increase of the oscillations near the jet boundary is assumed to be related to kinematic mixing intensification of the injected gas with the oncoming flow.

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Beratlis, Nikolaos, Francesco Capuano, Krishnamoorthy Krishnan, Roi Gurka, Kyle Squires, and Elias Balaras. "Direct Numerical Simulations of a Great Horn Owl in Flapping Flight." Integrative and Comparative Biology 60, no. 5 (September 14, 2020): 1091–108. http://dx.doi.org/10.1093/icb/icaa127.

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Synopsis The fluid dynamics of owls in flapping flight is studied by coordinated experiments and computations. The great horned owl was selected, which is nocturnal, stealthy, and relatively large sized raptor. On the experimental side, perch-to-perch flight was considered in an open wind tunnel. The owl kinematics was captured with multiple cameras from different view angles. The kinematic extraction was central in driving the computations, which were designed to resolve all significant spatio-temporal scales in the flow with an unprecedented level of resolution. The wing geometry was extracted from the planform image of the owl wing and a three-dimensional model, the reference configuration, was reconstructed. This configuration was then deformed in time to best match the kinematics recorded during flights utilizing an image-registration technique based on the large deformation diffeomorphic metric mapping framework. All simulations were conducted using an eddy-resolving, high-fidelity, solver, where the large displacements/deformations of the flapping owl model were introduced with an immersed boundary formulation. We report detailed information on the spatio-temporal flow dynamics in the near wake including variables that are challenging to measure with sufficient accuracy, such as aerodynamic forces. At the same time, our results indicate that high-fidelity computations over smooth wings may have limitations in capturing the full range of flow phenomena in owl flight. The growth and subsequent separation of the laminar boundary layers developing over the wings in this Reynolds number regime is sensitive to the surface micro-features that are unique to each species.

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Wang, Hai-Qiao, Gui-Rong Dong, Chun-Ling Bao, and Zhi-Hua Jiao. "Immediate Effect of Scalp Acupuncture on the Gait of Patients with Subacute Intracerebral Haemorrhage Analysed by Three-Dimensional Motion: Secondary Analysis of a Randomised Controlled Trial." Acupuncture in Medicine 36, no. 2 (April 2018): 71–79. http://dx.doi.org/10.1136/acupmed-2016-011272.

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Objective To investigate the immediate effect of scalp acupuncture on walking pattern, using three-dimensional gait analysis (3D-GA), among patients in the subacute stage of intracerebral haemorrhage (ICH). Methods A subset of 30 patients with subacute ICH participating in a recently published randomised controlled trial who were able to walk independently were assessed by 3D-GA before and immediately after scalp acupuncture treatment (treatment group) or no intervention (control group) and the results presented here as a secondary analysis. The acupuncture manipulation was repeated three times with an interval of 5 min. Spatiotemporal and kinematic parameters during walking were collected and analysed using a 3D motion analysis system. Results After treatment, there were significant differences between the treatment and control groups in the spatiotemporal parameters of step length, velocity and cadence (p<0.05) and double-limb support. No significant difference was found in step width. When kinematic parameters were evaluated, the treatment group showed a significantly decreased peak pelvic anterior tilt angle and an increased hip extension angle after scalp acupuncture treatment, whereas the control group demonstrated no temporal changes. There were no significant changes in any other kinematic parameters in either group. Conclusions As the first exploratory study to investigate the effect of the scalp acupuncture on gait performance in patients with subacute ICH, this secondary analysis of a recent randomised trial suggested an immediate effect of treatment on spatiotemporal parameters. Improvement in gait pattern may be associated with a decreased anterior tilt of the pelvis and augmented hip joint motion during walking. Trial Registration Number ChiCTR-TRC-08000225; Post-results.

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Knechtel, J., L. Klingbeil, J. H. Haunert, and Y. Dehbi. "OPTIMAL POSITION AND PATH PLANNING FOR STOP-AND-GO LASERSCANNING FOR THE ACQUISITION OF 3D BUILDING MODELS." ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences V-4-2022 (May 18, 2022): 129–36. http://dx.doi.org/10.5194/isprs-annals-v-4-2022-129-2022.

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Abstract. Terrestrial laser scanning has become more and more popular in recent years. The according planning of the standpoint network is a crucial issue influencing the overhead and the resulting point cloud. Fully static approaches are both cost and time extensive, whereas fully kinematic approaches cannot produce the same data quality. Stop-and-go scanning, which combines the strengths of both strategies, represents a good alternative solution. In the scanning process, the standpoint planning is by now mostly a manual process based on expert knowledge and relying on the surveyor’s experience. This paper provides a method based on Mixed Integer Linear Programming (MILP) ensuring an optimal placement of scanner standpoints considering all scanner-related constraints (e.g. incidence angle), a full coverage of the scenery, a sufficient overlap for the subsequent registration and an optimal route planning solving a Traveling Salesperson Problem (TSP). This enables the fully automatic application of autonomous systems for providing a complete model while performing a stop-and-go laser scanning, e.g. with the Spot robot from Boston Dynamics. Our pre-computed solution, i.e. standpoints and trajectory, has been evaluated surveying a real-world environment using a 360° panoramic laser scanner and successfully compared with a precise LoD2 building model of the underlying scene. The performed ICP-based registration issued from our fully automatic pipeline turns out to be a very good and safe alternative of the otherwise laborious target-based registration.

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Litvinenko, Y. V., Tomasz Niznikowski, and V. N. Boloban. "Evaluation of the kinematic structure of indicators key elements of sports equipment exercise by postural orientation movements." Physical education of students 18, no. 6 (December 28, 2014): 29–36. http://dx.doi.org/10.15561/20755279.2014.0606.

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Purpose : Examine the kinematic structure of indicators key elements of sports equipment exercise (difficult to coordinate). The method of postural orientation movements. Material : The study involved acrobats jumpers on the path of high qualification (n = 7). The method used video - computer recording the movements of the athlete. Results : Identified nodal elements of sports equipment double back somersault tuck. Exercise performed after rondat and double back flip and stretch after rondat - flick (coup ago). In the preparatory phase of motor actions acrobatic exercises isolated and studied central element of sports equipment - starting posture of the body; in the phase of the main motor action - animation poses of the body; in the final phase - the final body posture (stable landing). Conclusions : The method of video - computer registration allowed to perform a biomechanical analysis and evaluation of key elements of sports equipment double back somersault tuck and a double back flip and stretch. Also gain new knowledge about the mechanism of the phase structure of movements when performing double somersaults.

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Sugiura, Tsuyoshi, Yukitaka Nagamoto, Motoki Iwasaki, Masafumi Kashii, Takashi Kaito, Tsuyoshi Murase, Tetsuya Tomita, Hideki Yoshikawa, and Kazuomi Sugamoto. "In vivo 3D kinematics of the upper cervical spine during head rotation in rheumatoid arthritis." Journal of Neurosurgery: Spine 20, no. 4 (April 2014): 404–10. http://dx.doi.org/10.3171/2014.1.spine13252.

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Object The upper cervical spine is commonly involved in persons with rheumatoid arthritis (RA). Although 2D measurements have long been used in the evaluation of cervical lesions caused by RA, 2D measurements are limited in their effectiveness for detecting subtle and complex morphological and kinematic changes. The purpose of this study was to elucidate the 3D kinematics of the upper cervical spine in RA and the relationship between 3D morphological changes and decreased segmental rotational motion. Methods Twenty-five consecutive patients (2 men and 23 women, mean age 63.5 years, range 42–77 years) with RA (the RA group) and 10 patients (5 men and 5 women, mean age 69.9 years, range 57–82 years) with cervical spondylosis and no involvement of the upper cervical spine (the control group) underwent 3D CT of the cervical spine in 3 positions (neutral, 45° head rotation to the left, and 45° head rotation to the right). The segmental rotation angle from the occiput (Oc) to C-2 was calculated for each participant using a voxel-based registration method, and the 3D destruction of articular facets was quantified using the authors' own parameter, the articular facet index. Results The segmental rotation angle was significantly smaller at C1–2 and larger at Oc–C1 in the RA group compared with the control group. The degree of the destruction of the articular facet at C-1 and C-2 correlated with the segmental rotation angle. Conclusions In vivo 3D kinematics of the upper cervical spine during head rotation in patients with RA were accurately measured, allowing quantification of the degree of joint destruction for the first time. Joint destruction may play an important role in decreasing segmental motion of the upper cervical spine in RA.

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Di Paolo, Stefano, Piero Agostinone, Alberto Grassi, Gian Andrea Lucidi, Erika Pinelli, Marco Bontempi, Gregorio Marchiori, Laura Bragonzoni, and Stefano Zaffagnini. "Dynamic Radiostereometry Evaluation of 2 Different Anterior Cruciate Ligament Reconstruction Techniques During a Single-Leg Squat." Orthopaedic Journal of Sports Medicine 9, no. 7 (July 1, 2021): 232596712110119. http://dx.doi.org/10.1177/23259671211011940.

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Background: Lateral extra-articular tenodesis in the context of anterior cruciate ligament (ACL) reconstruction (ACLR) is performed to better control anterolateral knee instability in patients with high-grade preoperative pivot shift. However, some authors believe these procedures may cause lateral compartment overconstraint, affecting knee motion in daily life. Purpose/Hypothesis: The primary aim of the present study was to identify kinematic differences during the execution of an activity under weightbearing conditions between knees having undergone ACLR using anatomic single-bundle (SB) versus single-bundle plus lateral plasty (SBLP) techniques. The secondary aim was to compare the postoperative kinematic data with those from the same knees before ACLR and from the healthy contralateral knees in order to investigate if ACLR was able to restore physiologic knee biomechanics during squat execution. The hypotheses were that (1) the SBLP technique would allow a better restoration of internal-external (IE) knee rotation than would SB and (2) regardless of the technique, ACLR would not fully restore physiologic knee biomechanics. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: In total, 32 patients (42 knees) were included in the study. Patients were asked to perform a single-leg squat before surgery (ACL-injured group, n = 32; healthy contralateral group, n = 10) and at minimum 18-month follow-up after ACLR (SB group, n = 9; SBLP group, n = 18). Knee motion was determined using a validated model-based tracking process that matched patient-specific magnetic resonance imaging bone models to dynamic biplane radiographic images under the principles of roentgen stereophotogrammetric analysis. Data processing was performed using specific software. The authors compared IE and varus-valgus rotations and anterior-posterior and medial-lateral translations among the groups. Results: The mean follow-up period was 21.7 ± 4.5 months. No kinematic differences were found between the SB and SBLP groups ( P > .05). A more medial tibial position ( P < .05) of the ACL-injured group was reported during the entire motor task and persisted after ACLR in both the SB and the SBLP groups. Differences in IE and varus-valgus rotations were found between the ACL-injured and healthy groups. Conclusion: There were no relevant kinematic differences between SBLP and anatomic SB ACLR during the execution of a single-leg squat. Regardless of the surgical technique, ACLR failed in restoring knee biomechanics. Registration: NCT02323386 ( ClinicalTrials.gov identifier).

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Naydenko, E., and D. Zahumennov. "CONTROL SYSTEM OF TWO MASS ELECTROMECHANICAL SYSTEM BASED ON INDUSTRIAL CONTROLLER." ELECTRICAL AND COMPUTER SYSTEMS 33, no. 109 (December 22, 2020): 46–53. http://dx.doi.org/10.15276/eltecs.33.109.2020.5.

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It is possible to create a control program for a two-mass system based on an industrial micro- controller. The software implements various control methods to reduce the dynamic loads in the kinematic elements during the transients. The methods of simulating the behavior of the mechanism in different condi- tions and time intervals is described, as well as demonstration of the system operation and registration of relevant data. Numerous studies have shown that mechanical vibrations in most cases adversely affect the operation of the electric drive, causing an increase in dynamic loads, which reduces the accuracy of the mechanism, the occurrence of mechanical vibrations that create a dangerous situation. In the transients, when the suspension point of the load moves with acceleration, there is a swing of the load relative to its equilibrium position. The aim of the work is to control the mechanism of horizontal movement by an indus- trial controller, which implements the reduction of loads in the kinematic transmissions during the transi- ents, increases the speed and dampens the oscillations of the suspended load. The task is to develop a control algorithm and demonstrate the possibility of implementing the necessary control laws of the industrial con- troller. The possibility of realization of a microcontroller control of the asynchronous electric drive of the translational movement mechanism with the suspended load is shown, the control algorithm providing re- duction of the dynamic loadings in the kinematic elements is developed, and at small values of a backlash it provides speed and damping of the fluctuations suspended on a flexible thread. The management program is implemented on the basis of the industrial controller. It is possible to demonstrate the operation of the sys- tem in real time, as well as, changing the scale of time, to investigate the dynamic loads arising in the kine- matic elements of the mechanism under different conditions and control methods.

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47

Moiseev, K. V., A. I. Popenov, and R. N. Bakhtizin. "Express method for the testing of tribotechnical properties of lubricants." SOCAR Proceedings, SI2 (December 30, 2021): 65–69. http://dx.doi.org/10.5510/ogp2021si200586.

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The paper presents the results of experimental study of the tribotechnical properties of lubricants on a unit that simulates the geometric, kinematic and force similarity of well drilling conditions. Bearings with different radial clearances and the same chemical-thermal treatment were investigated. Data registration was carried out on cathode, loop oscilloscopes and electronic recorders. The load on the bearing, the moment of rolling resistance on the journal, and the angular speed of rotation of the outer race were recorded. The temperature was registered using artificial and semiartificial thermocouples. A strobotachometer was used to determine the portable speed of the rolling bodies. The external appearance of all rolling elements was investigated, metallographic analysis of thin surface layers of all rolling elements was carried out, mathematical processing of test results was carried out. It is shown that for the express assessment of the tribotechnical properties of lubricants, the amplitude value of the oscillation of the rolling resistance moment can be used. Keywords: friction; lubrication; tribotechnical Properties; drilling.

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Razavi, Christopher R., Paul R. Wilkening, Rui Yin, Samuel R. Barber, Russell H. Taylor, John P. Carey, and Francis X. Creighton. "Image-Guided Mastoidectomy with a Cooperatively Controlled ENT Microsurgery Robot." Otolaryngology–Head and Neck Surgery 161, no. 5 (July 23, 2019): 852–55. http://dx.doi.org/10.1177/0194599819861526.

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Mastoidectomy is a common surgical procedure within otology. Despite being inherently well suited for implementation of robotic assistance, there are no commercially available robotic systems that have demonstrated utility in aiding with this procedure. This article describes a robotic technique for image-guided mastoidectomy with an experimental cooperatively controlled robotic system developed for use within otolaryngology–head and neck surgery. It has the ability to facilitate enhanced operative precision with dampening of tremor in simulated surgical tasks. Its kinematic design is such that the location of the attached surgical instrument is known with a high degree of fidelity at all times. This facilitates image registration and subsequent definition of virtual fixtures, which demarcate surgical workspace boundaries and prevent motion into undesired areas. In this preliminary feasibility study, we demonstrate the clinical utility of this system to facilitate performance of a cortical mastoidectomy by a novice surgeon in 5 identical temporal bone models with a mean time of 221 ± 35 seconds.

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Bramanto, Brian, Irwan Gumilar, Muhammad Taufik, and I. Made D. A. Hermawan. "Long-range Single Baseline RTK GNSS Positioning for Land Cadastral Survey Mapping." E3S Web of Conferences 94 (2019): 01022. http://dx.doi.org/10.1051/e3sconf/20199401022.

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In Indonesia, Global Navigation Satellite System (GNSS) has become one of the important tool in survey mapping, especially for cadastral purposes like land registration by using Real Time Kinematic (RTK) GNSS positioning method. The conventional RTK GNSS positioning method ensure high accuracy GNSS position solution (within several centimeters) for baseline less than 20 kilometers. The problems of resolving high accuracy position for a greater distance (more than 50 kilometers) becomes greater challenge. In longer baseline, atmospheric delays is a critical factor that influenced the positioning accuracy. In order to reduce the error, a modified LAMBDA ambiguity resolution, atmospheric correction and modified kalman filter were used in this research. Thus, this research aims to investigate the accuracy of estimated position and area in respect with short baseline RTK and differential GNSS position solution by using NAVCOM SF-3040. The results indicate that the long-range single baseline RTK accuracy vary from several centimeters to decimeters due to unresolved biases.

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Fomenko, Anton, and Demitre Serletis. "Robotic Stereotaxy in Cranial Neurosurgery: A Qualitative Systematic Review." Neurosurgery 83, no. 4 (December 14, 2017): 642–50. http://dx.doi.org/10.1093/neuros/nyx576.

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Abstract BACKGROUND Modern-day stereotactic techniques have evolved to tackle the neurosurgical challenge of accurately and reproducibly accessing specific brain targets. Neurosurgical advances have been made in synergy with sophisticated technological developments and engineering innovations such as automated robotic platforms. Robotic systems offer a unique combination of dexterity, durability, indefatigability, and precision. OBJECTIVE To perform a systematic review of robotic integration for cranial stereotactic guidance in neurosurgery. Specifically, we comprehensively analyze the strengths and weaknesses of a spectrum of robotic technologies, past and present, including details pertaining to each system's kinematic specifications and targeting accuracy profiles. METHODS Eligible articles on human clinical applications of cranial robotic-guided stereotactic systems between 1985 and 2017 were extracted from several electronic databases, with a focus on stereotactic biopsy procedures, stereoelectroencephalography, and deep brain stimulation electrode insertion. RESULTS Cranial robotic stereotactic systems feature serial or parallel architectures with 4 to 7 degrees of freedom, and frame-based or frameless registration. Indications for robotic assistance are diversifying, and include stereotactic biopsy, deep brain stimulation and stereoelectroencephalography electrode placement, ventriculostomy, and ablation procedures. Complication rates are low, and mainly consist of hemorrhage. Newer systems benefit from increasing targeting accuracy, intraoperative imaging ability, improved safety profiles, and reduced operating times. CONCLUSION We highlight emerging future directions pertaining to the integration of robotic technologies into future neurosurgical procedures. Notably, a trend toward miniaturization, cost-effectiveness, frameless registration, and increasing safety and accuracy characterize successful stereotactic robotic technologies.

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