Ball's Motion Estimation Using a Line-Scan Camera

Abstract

An original method is proposed for estimating the position and velocity of a moving ball using a single line-scan camera. The method consists of two steps: firstly, the ball's initial position and velocity are determined by several key points in the image, and secondly, these parameters are further refined by a model-based optimization algorithm. The algorithm achieves accurate parameter estimation by matching the projection contour of the real ball and that of the same size sphere model. Finally, the relevance and accuracy of the method are experimentally confirmed on synthetic and real images.

Model-based Estimation for Pose, Velocity of Projectile from Stereo Linear Array Image

“…Since the line scan camera is working in one-dimension mode, only the space points on the viewing plane ( 0 x = ) can be projected on the image plane. The projection model of the line-scan camera is well described in [17][18][19]: the relationship between the 3D point [ , , ] T X Y Z = % % % % P in world coordinate and its corresponding point [ , ] T m x y ′ ′ = on the image plane is given by:…”

“…Moreover, the images of fast moving objects come sharp and crisp with no need for expensive and cumbersome strobe lighting and shuttering. The image is composed of plenty of lines which are sensed at different time instants, it therefore contains both spatial and temporal information of the target's movement, making it particularly possible to estimate high-speed motion [17].…”