Comparison of Markerless and Marker-Based Motion Capture Technologies through Simultaneous Data Collection during Gait: Proof of Concept

Abstract

During the last decade markerless motion capture techniques have gained an increasing interest in the biomechanics community. In the clinical field, however, the application of markerless techniques is still debated. This is mainly due to a limited number of papers dedicated to the comparison with the state of the art of marker based motion capture, in term of repeatability of the three dimensional joints' kinematics. In the present work the application of markerless technique to data acquired with a marker-based system was investigated. All videos and external data were recorded with the same motion capture system and included the possibility to use markerless and marker-based methods simultaneously. Three dimensional markerless joint kinematics was estimated and compared with the one determined with traditional marker based systems, through the evaluation of root mean square distance between joint rotations. In order to compare the performance of markerless and marker-based systems in terms of clinically relevant joint angles estimation, the same anatomical frames of reference were defined for both systems. Differences in calibration and synchronization of the cameras were excluded by applying the same wand calibration and lens distortion correction to both techniques. Best results were achieved for knee flexion-extension angle, with an average root mean square distance of 11.75 deg, corresponding to 18.35% of the range of motion. Sagittal plane kinematics was estimated better than on the other planes also for hip and ankle (root mean square distance of 17.62 deg e.g. 44.66%, and 7.17 deg e.g. 33.12%), meanwhile estimates for hip joint were the most incorrect. This technique enables users of markerless technology to compare differences with marker-based in order to define the degree of applicability of markerless technique.

A 2D Markerless Gait Analysis Methodology: Validation on Healthy Subjects

“…Specifically, Sandau et al [3] reported a RMSD of 2.6 deg for the hip, 3.5 deg for the knee, and 2.5 deg for the ankle, which are comparable with the RMSD values reported in Table 2 for the comfortable gait speed. Ceseracciu et al [4] reported a RMSD of 17.6 deg for the hip, 11.8 deg for the knee, and 7.2 deg for the ankle, sensibly higher than the values reported in this work. This further confirms the potential of the SEGMARK approach for the study of the lower limb motion in the sagittal plane for clinical applications.…”

“…However, in the abovementioned studies, the analyses were either limited to a single joint [20, 21], or they lacked a validation against a clinically accepted gold standard [22, 23]. These limitations hampered the wide spread use of such techniques in clinical settings [4, 7, 9]. …”

Human to humanoid motion conversion for dual-arm manipulation tasks

“…The most commonly used techniques for recording human movement are marker-based and marker-less motion capture systems. Comparative analyses of different motion capture systems are given in references [5][6][7]. In order to record a 3D model of human motion, including the position and orientation of the required segments and joints, in this research we used an ART marker-based motion capture system.…”

A Real-Time Kinect Signature-Based Patient Home Monitoring System

“…Typically using markers attached to the patient’s body, such systems are accurate and deployed in many gait analysis laboratories [19], but are expensive, limited in range to the laboratory, and are limited to Line of Sight (LoS) conditions and to the markers’ locations. Existing marker-less video systems are less accurate, require multiple synchronized cameras [17], and sometimes still require an expert’s analysis of the resulting video streams [20]. …”