Three-dimensional videography of swimming with panning periscopes

Yanai, Toshimasa; Hay, James G.; Gerot, John T.

doi:10.1016/0021-9290(95)00123-9

Cited by 28 publications

(30 citation statements)

References 4 publications

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“…After the completion of self-motivated warm-up exercises, each swimmer was asked to perform front-crawl swimming at a distance-pace and a submaximum sprinting pace for two lengths of a 22.9 m pool (1.370.1 m/s and 1.670.1 m/s, respectively). A three-dimensional videography technique with panning periscopes (Yanai et al, 1996) was used to determine the position and orientation of each body segment of the swimmer throughout the stroke cycle. The camcorders fixed to the periscopes (Panasonic AG 450-SVHS) were operated to record at 60 fields per second.…”

Section: Methodsmentioning

confidence: 99%

Buoyancy is the primary source of generating bodyroll in front-crawl swimming

Yanai

2004

Journal of Biomechanics

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Section: Methodsmentioning

confidence: 99%

Buoyancy is the primary source of generating bodyroll in front-crawl swimming

Yanai

2004

Journal of Biomechanics

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“…The wand and 2D plate calibration methods (8 and 16 CP) led to underwater accuracy better than previously reported in the literature (MAE values of 5.12 mm were found in Yanai et al, 1996; RMS value of 5.6 mm and maximum error of 9.3 mm were detected in Kwon and Lindley, 2000; %RMS value of 1.28% was obtained in Gourgoulis et al, 2008; and RMS value of 5.2 mm was presented in Machtsiras and Sanders, 2009). It is well known that the number and the distribution of the CP strongly affect the DLT (Kwon and Lindley, 2000).…”

Section: Discussionmentioning

confidence: 43%

Comparison of different camera calibration approaches for underwater applications

Silvatti

Dias

Cerveri

et al. 2012

Journal of Biomechanics

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a b s t r a c tThe purpose of this study was to compare three camera calibration approaches applied to underwater applications: (1) static control points with nonlinear DLT; (2) moving wand with nonlinear camera model and bundle adjustment; (3) moving plate with nonlinear camera model. The DVideo kinematic analysis system was used for underwater data acquisition. The system consisted of two gen-locked Basler cameras working at 100 Hz, with wide angle lenses that were enclosed in housings. The accuracy of the methods was compared in a dynamic rigid bar test (acquisition volume-4.5 Â 1 Â 1.5 m 3 ). The mean absolute errors were 6.19 mm for the nonlinear DLT, 1.16 mm for the wand calibration, 1.20 mm for the 2D plate calibration using 8 control points and 0.73 mm for the 2D plane calibration using 16 control points. The results of the wand and 2D plate camera calibration methods were less associated to the rigid body position in the working volume and provided better accuracy than the nonlinear DLT. Wand and 2D plate camera calibration methods presented similar and highly accurate results, being alternatives for underwater 3D motion analysis.

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“…Experiment Camera settings Data capture area (m) e x (mm) e y (mm) e z (mm) e D (mm) Angulo and Dapena (1992 Raschner (1997) Field P, T, Z 29.9 6 11.7 6 10.3 7 7 9.2 13.5* Schwameder (1994) Field P, T 46.7 6 11.8 6 13.0 10 7 7 14* Yanai et al (1996) Field P 1.5 6 8.4 6 2.0 9.2 5.6 2.6 11.1 Yeadon (1989) Field P,T 100 6 10 6 5 -- Accuracy of kinematic data in a field setting 1349 smaller measurement volume, and the use of static cameras. Photogrammetric errors in the present study are only slightly higher than in the field studies mentioned in Table I (8.8 mm difference).…”

Section: Studymentioning

confidence: 99%

Collecting kinematic data on a ski/snowboard track with panning, tilting, and zooming cameras: Is there sufficient accuracy for a biomechanical analysis?

Klous

Müller

Schwameder

2010

Journal of Sports Sciences

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For biomechanical research in several sports (e.g. skiing and snowboarding), field experiments are essential because these activities are performed over a great distance and in conditions that could not be reproduced in a controlled laboratory environment. High technical standards in kinematic set-up are necessary to achieve the required accuracy for biomechanical analysis. The purpose of this study was to determine the accuracy of the kinematic data collected in a ski and snowboard field experiment. Eight tests generally used in laboratory settings were adapted to field conditions on a skiing slope to determine the error related to motion capture. The calculated photogrammetric errors in the x-, y-, and z-direction were 11 mm, 9 mm, and 13 mm, respectively. The maximum error caused by soft tissue artifacts was 39 mm. These results indicate that accuracy of kinematic data in the described field experiment was comparable to that found in literature for laboratory experiments. It may be concluded that accurate kinematic data collection for skiing and snowboarding can be performed in a field setting and that these results are accurate enough to serve as input data for further analyses.

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Three-dimensional videography of swimming with panning periscopes

Cited by 28 publications

References 4 publications

Buoyancy is the primary source of generating bodyroll in front-crawl swimming

Buoyancy is the primary source of generating bodyroll in front-crawl swimming

Comparison of different camera calibration approaches for underwater applications

Collecting kinematic data on a ski/snowboard track with panning, tilting, and zooming cameras: Is there sufficient accuracy for a biomechanical analysis?

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