5 results about "Spin axis" patented technology

Methods and apparatus, including computer program products, implementing, and using techniques for determining a spin axis of a ball in flight. At least a portion of an observed trajectory of the ball is obtained. The trajectory includes three-dimensional locations of the ball over time, as determined from individual observations of the ball by one or more sensors. A point in three-dimensional space is selected. An optimization problem is solved, wherein the three-dimensional acceleration at the selected point is used as an optimization target, and a spin axis, a spin magnitude and a wind vector are used as optimization parameters, and wherein the solution to the optimization problem is a combination of optimization parameter values. The spin axis determined in the solution to the optimization problem is selected as the spin axis for the ball. The spin axis is used to generate ball trajectory information for presentation on an output device.

The embodiment of the application discloses a kind of ring sweep imaging satellite's rotation control method, device and medium;The method can include: according to the kinematics equation constructed by (w,z) parameter and the dynamics equation constructed by rigid model, the reference value w of parameter w for describing spin axis pointing is obtained by time integration r ;Rotation stage: without introducing the parameter z for describing the rotation angle around spin axis, the parameter w obtained by the first reference value w r Parameter error w e And angular velocity error ω e First control law is designed for rotation control, and is switched to spin angle control stage after rotation stabilizes;Spin angle control stage: the value of parameter z at switching time is used as the initial value of the reference value z r Of parameter z, and according to the kinematics equation constructed by (w,z) parameter and the dynamics equation constructed by rigid model, subsequent reference value z r Is obtained by time integration;According to the reference value z r Of the parameter z, the error z e Of parameter z is introduced, and the second control law for spin angle control is designed according to the error z e Of the parameter z and the first control law.

A spin calculation method for a golf ball moving by being hit according to an embodiment of the present invention comprises: acquiring a first image and a second image, which are consecutive images for the golf ball with a plurality of markers to be hit and moved, respectively; processing to obtain information on a reference marker and a plurality of peripheral markers around the reference marker for a plurality of markers on a first ball image corresponding to a golf ball in the first image; specifying a combination of markers corresponding to the reference marker and the peripheral markers on the first ball image among markers in a second ball image corresponding to a golf ball in a second image; and processing to calculate a spin axis and a spin amount of the moving golf ball using each center point of a pair of markers corresponding to each other on the first ball image and the second ball image.

Embodiments are disclosed for determining a spin rate and axis of a ball using deep learning. In some embodiments, a method comprises: training a deep learning network on training images of spinning balls, each spinning ball having at least one feature point in a time series that forms a two-dimensional (2D) ellipse image in a 2D plane; capturing, with at least one camera, a series of images of a ball; predicting, with the trained deep learning network, spin measurements associated with the ball based on the series of images; determining a spin rate of the ball based on the spin measurements; determining coefficients of a 2D ellipse model based on the spin measurements and the spin rate; and determining, with the at least one processor, a spin axis of the ball in 3D space based on the 2D ellipse model and the spin rate.

The purpose of the present invention is to provide a method for measuring spin information of a ball hit and moved. When a ball used in sports such as golf is hit and moved while rotating, a reflected Doppler signal of a radar signal is received, and digital data of the received signal is acquired and analyzed. Accordingly, the spin axis of the moving ball is calculated in a new manner that cannot be predicted by conventional technology, thereby improving the accuracy of spin axis calculation.