SYSTEM FOR SPORTS ACTIVITY

• US 20100249958A1
• Filed: 10/31/2008
• Published: 09/30/2010
• Est. Priority Date: 10/31/2007
• Status: Abandoned Application

• Current Assignee: A4SP Technologies Oy
• Original Assignee: A4SP Technologies Oy
• Inventors: Jylhä, Antti, Välimäki, Vesa, Salmi, Timo, Erkut, Cumhur, Salmi, Tomi
• Application Number:
  US12/740,963
• Publication Number:
  US 20100249958A1
• Time in Patent Office: Days
• US Class Current: 700/91
• CPC Class Codes: A63B 2024/0028 Tracking the path of an object, e.g. a ball inside a soccer pitch
• CPC Class Codes: A63B 2024/0031 at the starting point
• CPC Class Codes: A63B 2024/0037 on a target surface or at impact on the ground
• CPC Class Codes: A63B 2024/0056 for statistical or strategic analysis
• CPC Class Codes: A63B 2220/53 Force of an impact, e.g. blow or punch
• CPC Class Codes: A63B 2220/64 Frequency, e.g. of vibration oscillation
• CPC Class Codes: A63B 2220/80 Special sensors, transducers or devices therefor
• CPC Class Codes: A63B 2220/833 Sensors arranged on the exercise apparatus or sports implement
• CPC Class Codes: A63B 24/0021 Tracking a path or terminating locations
• CPC Class Codes: A63B 49/00 Stringed rackets, e.g. for tennis strings therefor A63B51/00
• CPC Class Codes: A63B 60/46 Measurement devices associated with golf clubs, bats, rackets or the like for measuring physical parameters relating to sporting activity, e.g. baseball bats with impact indicators or bracelets for measuring the golf swing
• CPC Class Codes: A63B 63/00 Targets or goals for ball games golf cups A63B57/40
• CPC Class Codes: A63B 69/0002 for baseball
• CPC Class Codes: A63B 69/002 for football American-football dummies A63B69/34
• CPC Class Codes: A63B 69/0024 for hockey
• CPC Class Codes: A63B 69/0097 Ball rebound walls with holes or in combination with nets A63B63/00

Abstract

A system for a sports activity, which system is adapted to detect potential game contacts that include contacts between games equipment (1) and a games object (2) and/or contacts between a games object (2) and a target surface (5), and the system comprises sensor means (3a, 3b) adapted to detect vibrations caused by potential game contacts and to convert these vibrations into sensor signals. The system is adapted to

• define the value of the sensor signal at several consecutive discrete time instants,
• define for a sensor signal section within a time frame k that contains N sensor signal values an energy value quantity E[k] that is related to the energy of the sensor signal section,
• repeat the above step of defining the energy value quantity of the sensor signal section for several consecutive time frames, and
• detect a potential game contact by utilizing a detection function D that is obtained by a linear combination of energy value quantities of sensor signal sections contained in consecutive time frames by using the formula

$D\left[k\right]=\sum _{i=0}^{K-1}c_iE\left[k-i\right],$

wherein K is the number of energy value quantities used in calculation and an integer equal to or greater than two, and c_i is a weighting coefficient for the energy value quantity E[k−i], whereby the detection of a potential game contact in the time frame k is based on comparing the value D[k] of the detection function D corresponding to the time frame k is compared with a threshold value.

Claims

1. A system for a sports activity, which system is adapted to detect potential game contacts that include contacts between games equipment and a games object and/or contacts between a games object and a target surface, and the system comprises sensor means adapted to detect vibrations caused by potential game contacts and to convert these vibrations into sensor signals, wherein the system is adapted to

define the value of the sensor signal at several consecutive discrete time instants,

define for a sensor signal section within a time frame k that contains N sensor signal values an energy value quantity E[k] that is related to the energy of the sensor signal section,

repeat the above step of defining the energy value quantity of the sensor signal section for several consecutive time frames, and

detect a potential game contact by utilizing a detection function D that is obtained by a linear combination of the energy value quantities of the sensor signal sections contained in the consecutive time frames by using the formula

2. A system as claimed in claim 1, wherein the consecutive time frames may partially overlap.

3. A system as claimed in claim 1, wherein potential game contacts, the vibrations caused by which the sensor means are adapted to detect, comprise a contact between games equipment and a games object, and the system detects a potential game contact if the detection function D obtains in the examined time frame a higher value than an adaptive threshold value function A, that is, when

D[k]>

A[k].

4. A system as claimed in claim 3, wherein the adaptive threshold value function A is defined as follows:

5. A system as claimed in claim 3, wherein the sensor means comprise a games equipment sensor that is adapted to be fastened to the games equipment and to detect vibrations caused in the games equipment by a contact between the games equipment and games object.

6. A system as claimed in claim 1, wherein potential game contacts, the vibrations caused by which the sensor means are adapted to detect, comprise a contact between the games object and target surface, and the sensor means comprise a target surface sensor that is adapted to be connected to the target surface and to detect vibrations caused in the target surface by a contact between the games object and target surface.

7. A system as claimed in claim 1, wherein the energy value quantities of the sensor signal sections are effective values, whereby the energy value quantity for a time frame ending at time instant n is obtained from the formula

8. A system as claimed in claim 1, wherein to avoid error detections, the system is adapted to use a double detection time constant in such a manner that during a period of the length of the double detection time constant after a potential game contact, the system does not detect potential game contacts, even though their criteria for detection were met.

9. A system as claimed in claim 1, wherein in that the system is also adapted to classify detected potential game contacts by using at least one classification algorithm that is adapted to determine whether a potential game contact is an actual game contact or error detection.

10. A system as claimed in claim 1, wherein the system is also adapted to provide each detected potential game contact a time stamp that is associated with the time when the potential game contact took place.