A posture optimization algorithm for model-based motion capture of movement sequences

Autor: Volker Dürr, Jure Zakotnik, Tom Matheson
Rok vydání: 2003
Předmět:
leg
Work
Insecta
Time Factors
Computer science
ACCURACY
Performance
Kinematics
Walking
Search algorithm
Computer vision
Simulated Annealing
Image resolution
JOINT
Occlusion
General Neuroscience
Tracking
Signal Processing
Computer-Assisted
Neuroethology
Equipment Design
body
TIME
Biomechanical Phenomena
Algorithm
Simulated annealing
MOTOR
Algorithms
Kinematic chain
FRAMES
Movement
Posture
ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION
system
Motion capture
Models
Biological
Motion
Imaging
Three-Dimensional
Motor control
Motion estimation
motion capture
Animals
Stick Insect
Leg movement
ComputingMethodologies_COMPUTERGRAPHICS
MOVEMENTS
model
SEQUENCES
business.industry
movement sequence
Videotape Recording
Extremities
Locust
Error function
insect
Joints
Artificial intelligence
Resolution
business
control
Zdroj: Journal of neuroscience methods. 135(1-2)
ISSN: 0165-0270
Popis: We have developed and evaluated a new optical motion capture approach that is suitable for a wide range of studies in neuroethology and motor control. Based on the stochastic search algorithm of Simulated Annealing (SA), it utilizes a kinematic body model that includes joint angle constraints to reconstruct posture from an arbitrary number of views. Rather than tracking marker trajectories in time, the algorithm minimizes an error function that compares predicted model projections to the recorded views. Thus, each video-frame is analyzed independently from other frames, enabling the system to recover from incorrectly analyzed postures. The system works with standard computer and video equipment. Its accuracy is evaluated using videos of animated locust leg movements, recorded by two orthogonal views. The resulting joint angle RMS errors range between 0.7 degrees and 4.9 degrees, limited by the pixel resolution of the digital video. 3D-movement reconstruction is possible even from a single view. In a real experimental application, stick insect walking sequences are analyzed with leg joint angle deviations between 0.5 degrees and 3.0 degrees. This robust and accurate performance is reached in spite of marker fusions and occlusions, simply by exploiting the natural constraints imposed by a kinematic chain and a known experimental setup.
Databáze: OpenAIRE
Externí odkaz: