METHOD FOR SWING RESULT DEDUCTION AND POSTURE CORRECTION AND THE APPARATUS OF THE SAME
An exemplary embodiment provides a method for swing result deduction and posture correction. The method includes performing a coordinate transformation between a sensor frame and an earth frame, deducting the swing result according to at least one piece of sensor information and a swing result deduction analysis, and providing a posture correction advice according to at least one piece of sensor information and a posture correction analysis.
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This application claims the priority benefit of Taiwan application serial no. 101137614, filed on Oct. 12, 2012. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
BACKGROUND1. Field of the Disclosure
The technical field of the present disclosure is related to a method for swing result deduction and posture correction and the device thereof.
2. Description of the Related Art
In the sport of golf, common misplayed shots include a hook, a slice, a pull, a push, a duff and a top, and a golf beginner usually does not know the type of misplayed shot made during practice as well as a correction method. Such a problem may be solved through one-to-one teaching by an instructor; however, due to the lack of accurate swing and golfer body information, an instructor can only instruct a golf beginner on how to correct a body movement from the experience based on a swing result. Such a problem may also be solved by recording swing information and the swing posture of a golf beginner with a high speed camera; however, such an approach may still encounter problems such as image obstruction (blind spot of camera), golfer privacy, an unknown body force application, and detection failure of the rotation angle of a club-face.
In another solution, a pressure sensor is installed on a golf club to record the force application on a club-head and feed back the force of a player's swing and the flying direction of a ball. However, such a golf club requires special fabrication, which is not economical. In yet another solution, a light distribution sensor is added in a striking environment to observe the flying shadow of a ball, determine the flying direction of the ball based on the tangent plane point of the swing, and predict a golf three dimensional movement trajectory. Such a method is not suitable for an outdoor practical swing and but only suitable for an indoor small-range operation.
Therefore, it is necessary to develop a method for swing result deduction and posture correction and a specific structure thereof, so that a golfer who intends to improve the golf skill may correct postures of ball striking by using objective data information. In addition, this set of method and structure may also provide a golf instructor with more precise, objective data to make better advices.
SUMMARY OF THE DISCLOSUREOne embodiment of the present disclosure provides a method for swing result deduction and posture correction, the method includes performing coordinate transformation between a sensor frame and an earth frame; outputting a swing result according to at least one piece of sensor information and through a swing result deduction analysis method; and outputting a correction advice according to at least one piece of sensor information and through a posture correction analysis method.
Another embodiment of the present disclosure provides an electronic device for swing result deduction and posture correction, capable of receiving sensor information generated by at least one sensor, and the electronic device includes a memory; and a processor including a coordinate transformation module, a swing result deduction module, and a posture correction module. The coordinate transformation module is used for performing coordinate transformation between the coordinates of the at least one sensor and an earth frame; the swing result deduction module is used for outputting a swing result according to the sensor information generated by the at least one sensor and through a swing result deduction analysis method; and the posture correction module is used for outputting a correction advice according to the sensor information generated by the at least one sensor and through a posture correction analysis method.
The foregoing has outlined rather broadly the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter, which form the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures or processes for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure as set forth in the appended claims.
The disclosure will be described according to the appended drawings in which:
The method and process in an application scenario of a method and a device for swing result deduction and posture correction provided in the present disclosure are as follows. In an embodiment, a ball striker may dispose a sensor, for example, a movement sensing accessory on the grip of a golf club, place a sensor through a method for connecting a sensor and a golf club, for example, an appendage or a fixation outside a golf club or an insertion in a golf club, and optionally wear a smartphone with a sensing function at the waist. When the movement sensing accessory and the smartphone are respectively positioned, swing practice may start. During each swing practice, a trainee or the ball striker needs to keep still for several seconds during the preparation for a take-away movement, and the movement sensing accessory may measure the current gravity and magnetic force and return the current gravity and magnetic force to a framework including the deduction and posture correction device for calculating a “sensor frame-earth frame” transformation matrix during the current take-away movement. Next, start a swing motion till the swing is completed, and at the same time, the measured sensed information are returned to the framework, so that the framework first transforms all the information back to the sensor frame during the take-away, and then, through a “sensor frame-earth frame” transformation procedure, transforms the sensed information into information using the earth frame as a reference. Next, the framework calculates a swing trajectory, an angle of a club-face and an acceleration value of a golf club, and determines a swing result. When a misplayed shot is made, the framework automatically determines the major cause for an undesirable swing result based on the deduced swing result in combination with the body movement of the ball striker determined by the sensor.
The coordinate transformation module 14 in the electronic device 100 in
As sensor information, for example, an acceleration value and a swing trajectory required for the process of determining a swing result is based on the reference of the earth frame, and the sensing device 24 may be unable to be precisely placed along the direction of the club. Therefore, coordinate transformation between a sensor frame and the earth frame is required. A ball striker first keeps still for several seconds during the preparation for a take-away movement, so that the gravity sensor and the magnetic sensor in the sensing device 24 are able to measure the current gravity and magnetic force and returns the current gravity and magnetic force to the framework. As shown in
where {right arrow over (M)} and {right arrow over (g)} are the measured magnetic force and gravity acceleration during the take-away preparation movement, respectively. Therefore, it may be obtained that the transformation matrix Te:s for transformation from the earth frame into the sensor frame is as follows:
where [v]s is the sensor frame and [v]e is the earth frame. The transformation matrix Ts:e for transformation from the sensor frame into the earth frame is:
Ts:e=Te:s−1.
By adopting the following equations, the sensor frame during the take-away preparation movement may be transformed into the earth frame:
[v]e=Te:s−1[v]s=Ts:e[v]s.
In an embodiment, the framework transforms the data returned by the sensor from the sensor frame into the earth frame according to the description below. First, the angular speeds (ωx,ωy,ωz) measured by a gyro sensor in each time of sampling are introduced to obtain a quaternion Q. After the sampling is completed, a sensor frame Qn:1 at the time of the take-away may be obtained through the vector product multiplication of quaternions Q generated at different sampling points. Next, the sensor frame Qn:1 at the time of the take-away is introduced into a corresponding rotation matrix R, and the value of a corresponding acceleration a is taken, so that the acceleration value of the sensor frame at the time of the take-away is obtained. Next, all obtained acceleration values of the sensor frame of the sampling points at the time of the take-away are taken into the transformation matrix Te:s to obtain the acceleration transformed into the “earth frame”. The computation equation is as follows:
it is assumed that the sampling rate is 1/Δt,
so that
ω=(ωx, ωy, ωz), ∥ω∥=√{square root over (ωx2+ωy2+ωz2)}, θ=∥ω∥Δt,
and the rotation is expressed through a quaternion as follows:
It may be derived from the quaternion that the rotation matrix R is as follows:
and q02+q12+q22+q32=1, and R may be simplified into:
Qn is expressed as the quaternion of the nth sampling point in the current sensor frame, the sensor frame at the time of the take-away is the vector product multiplication of the quaternion:
Qn:1=Qn×Qn−1 . . . ×Q1.
Qn:1 is introduced into the rotation matrix R to obtain Rn:1, so that the measurement data [v]s
[v]e=Ts:e[v]s=Ts:e(Rn:1[v]s
The swing result deduction module 16 in the electronic device 100 in
The trend of the rotation angle of the club-face along the X-axis may be illustrated through
In addition, different downswing trajectories and angles of the club-face may be formed into four different swing results: the combination of downswing trajectory outside-in and the closed club-face make a pull, the combination of downswing trajectory outside-in and the open club-face make a slice, the combination of downswing trajectory inside-out and the closed club-face make a hook, and the combination of downswing trajectory inside-out and the open club-face make a push. Therefore,
As there are many causes for a misplayed shot, if the type of the cause fails to be determined, it is impossible to give an effective correction advice. For example, in terms of body movement, there are over 10 causes for a hook, which might be related to the gripping of club, stance, center of gravity of the body, wrist turning, over-tight arms, and coordination between the upper body and lower body. In the present disclosure, the sensed movement information from multiple sensors and the causal relationship between body movement and sensed movement information are combined to determine the major cause of an undesirable swing result. See
The analysis method used in the posture correction module 18 in
In combination with the illustration in the last paragraph, the recording of time, the movement trajectory of golf club and the displacement amount of the waist of a user, may be separately or together added in the determination process of the posture correction module 18. For example, in the movement trajectory of golf club, the swing motion may be divided into different phases, for example, take-away, back-swing, transition, downswing, follow-through, and completion, to calculate the tempo of back-swing and downswing; the displacement amount of the waist may be used to learn the lateral and vertical movement of the center of gravity. In addition, as a swing result might be affected by more than one movement posture, in an embodiment, sensor information generated by a plurality of sensors are used for deduction. For example, the degree that the left arm is tightly held may be found out through the downswing trajectory; however, it still needs to be determined in advance whether there are influences of ball position and stance; the degree that the right wrist turns may be found out through the rotation angle of the golf club; however, it still needs to be determined in advance whether there is influences of the premature lower body turn.
Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. For example, many of the processes discussed above can be implemented in different methodologies and replaced by other processes, or a combination thereof.
Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present disclosure. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.
Claims
1. A method for swing result deduction and posture correction, comprising:
- performing coordinate transformation between a sensor frame and an earth frame;
- outputting a swing result according to at least one piece of sensor information and through a swing result deduction analysis method; and
- outputting a correction advice according to at least one piece of sensor information and through a posture correction analysis method.
2. The method for swing result deduction and posture correction according to claim 1, wherein the swing result deduction analysis method and the posture correction analysis method comprise:
- calculating a movement trajectory of a golf club, a movement occurrence time of the golf club, and a acceleration value of the movement of the golf club;
- calculating a rotation angle of a club-face; and
- calculating a displacement amount of the waist of a user and a movement occurrence time of the user.
3. The method for swing result deduction and posture correction according to claim 2, wherein the swing result deduction analysis method comprises:
- determining whether an acceleration value along the club has at least two regional maximum values with a difference between the two regional maximum values greater than a predetermined value, and outputting a first swing result.
4. The method for swing result deduction and posture correction according to claim 3, wherein the swing result deduction analysis method further comprises:
- determining whether a variation of an acceleration value along a target line within a specific time interval after an impact is greater than one specific value, and outputting a second swing result.
5. The method for swing result deduction and posture correction according to claim 4, wherein the swing result deduction analysis method further comprises:
- determining whether an angle of the club-face is greater than a predetermined value, if yes, determining whether the movement trajectory of the golf club is inside-out; if yes, outputting a third swing result; and if no, outputting a fourth swing result;
- if no, determining whether the movement trajectory of the golf club is inside-out; if yes, outputting a fifth swing result; and if no, outputting a sixth swing result.
6. The method for swing result deduction and posture correction according to claim 2, wherein the posture correction analysis method comprises:
- according to the movement trajectory of the golf club and the movement occurrence time, determining whether the movement trajectory of the golf club is inside-out, if yes, outputting a first correction advice.
7. The method for swing result deduction and posture correction according to claim 2, wherein the posture correction analysis method comprises:
- according to the movement trajectory of the golf club and the movement occurrence time of the golf club, determining whether the ratio of the back-swing time and the downswing time of the golf club is between 2:1 and 3:1, and if no, outputting a second correction advice.
8. The method for swing result deduction and posture correction according to claim 2, wherein the posture correction analysis method comprises:
- according to the displacement amount of the waist of the user and the movement occurrence time of the user, determining whether horizontal or vertical displacement of the waist of the user between the position at the take-away and the position at the striking point is greater than a predetermined value, and if yes, outputting a third correction advice.
9. The method for swing result deduction and posture correction according to claim 2, wherein the posture correction analysis method comprises:
- according to the movement trajectory of the golf club and the movement occurrence time of the golf club, and the displacement amount of the waist of the user and the movement occurrence time of the user, determining whether the movement of the golf club is earlier than the movement of the waist, and outputting a fourth correction advice.
10. The method for swing result deduction and posture correction according to claim 9, wherein the posture correction analysis method further comprises:
- determining whether the rotation angle of the club-face is greater than a predetermined value, and if yes, outputting a fifth correction advice.
11. An electronic device for swing result deduction and posture correction, capable of receiving sensor information generated by at least one sensor, and comprising:
- a memory; and
- a processor, comprising: a coordinate transformation module, used for performing coordinate transformation between the coordinates of the at least one sensor and an earth frame; a swing result deduction module, used for outputting a swing result according to the sensor information generated by the at least one sensor and through a swing result deduction analysis method; and a posture correction module, used for outputting a correction advice according to the sensor information generated by the at least one sensor and through a posture correction analysis method.
12. The electronic device for swing result deduction and posture correction according to claim 11, wherein the processor further comprises a wireless module, used for receiving the sensor information.
13. The electronic device for swing result deduction and posture correction according to claim 11, wherein the information output by the swing result deduction module and the posture correction module comprises:
- a movement trajectory of a golf club, a movement occurrence time of the golf club, an acceleration value of the movement of the golf club, a rotation angle of a club-face, the ratio between a back-swing time and a downswing time of the golf club, a displacement amount of the waist of a user and a movement occurrence time of the user, horizontal or vertical displacement of the waist of the user between the position at the take-away and the position at the striking point.
14. The electronic device for swing result deduction and posture correction according to claim 13, wherein the swing result deduction analysis method outputs a first swing result according to the sensor information that an acceleration value along the club has at least two regional maximum values with a difference between the at least two regional maximum values greater than a predetermined value.
15. The electronic device for swing result deduction and posture correction according to claim 13, wherein the swing result deduction analysis method outputs a second swing result according to the sensor information that a variation of an acceleration value in a target line is greater than one specific value within a specific time interval after an impact.
16. The electronic device for swing result deduction and posture correction according to claim 13, wherein the swing result deduction analysis method outputs one of the following: a third swing result, a fourth swing result, a fifth swing result, and a sixth swing result according to the sensor information of an angle of the club-face and the movement trajectory of the golf club.
17. The electronic device for swing result deduction and posture correction according to claim 13, wherein the sensor is combined with the golf club in a manner of an appendage outside the golf club or inside the golf club.
18. The electronic device for swing result deduction and posture correction according to claim 13, wherein the posture correction analysis method outputs a first correction advice according to the sensor information of the movement trajectory of the golf club, the movement occurrence time of the golf club, and the downswing trajectory is inside-out.
19. The electronic device for swing result deduction and posture correction according to claim 13, wherein the posture correction analysis method outputs a second correction advice according to the sensor information of the movement trajectory of the golf club, the movement occurrence time of the golf club, and the ratio of the back-swing time and the downswing time of the golf club.
20. The electronic device for swing result deduction and posture correction according to claim 13, wherein the posture correction analysis method outputs a third correction advice according to the sensor information of the displacement amount of the waist of the user, the movement occurrence time of the user, and the horizontal or vertical displacement of the waist of the user between the position at the take-away and the position at the striking point.
21. The electronic device for swing result deduction and posture correction according to claim 13, wherein the posture correction analysis method outputs a fourth correction advice according to the sensor information that the movement of the golf club is earlier than the movement of the waist.
22. The electronic device for swing result deduction and posture correction according to claim 21, wherein the posture correction analysis method outputs a fifth correction advice according to the sensor information that the rotation angle of the club-face is greater than a predetermined value.
23. A golf assembly, comprising:
- a golf club; and
- a sensing device, comprising at least a gyro sensor, a gravity sensor, and a magnetic sensor,
- wherein the sensing device is combined with the golf club in a manner of an appendage outside the golf club or an insertion inside the golf club.
24. The golf assembly according to claim 23, further comprising an electronic device as in claim 11.
25. The golf assembly according to claim 23, wherein the sensing device is screwed to a detachable sleeve ring jacketed on the golf club.
26. The golf assembly according to claim 23, wherein the sensing device is screwed to the golf club.
27. The golf assembly according to claim 23, wherein the sensing device is inserted in the groove of a sleeve ring jacketed on the golf club.
28. The golf assembly according to claim 26, wherein the sleeve ring is located below or above a grip position.
29. The golf assembly according to claim 23, wherein the sensing device is fixated at the interior surface of the golf club.
Type: Application
Filed: Dec 21, 2012
Publication Date: Apr 17, 2014
Applicants: NATIONAL CHIAO TUNG UNIVERSITY (HSINCHU), INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE (HSINCHU)
Inventors: CHUNG WEI LIN (CHANGHUA COUNTY), LUN CHIA KUO (TAICHUNG CITY), CHIH WEI YI (HSINCHU COUNTY), YU JUNG YEH (HSINCHU COUNTY), TSUNG LONG CHEN (TAINAN CITY), YI CHEN HUANG (KAOHSIUNG CITY)
Application Number: 13/725,778
International Classification: A63B 69/36 (20060101);