CA3006829A1

CA3006829A1 - Curling rocks, handles, and systems and methods for tracking play objects

Info

Publication number: CA3006829A1
Application number: CA3006829A
Authority: CA
Inventors: Jonathan GUILLEMETTE; Martin Cavanagh
Original assignee: Intellisports Inc
Current assignee: Intellisports Inc
Priority date: 2017-05-31
Filing date: 2018-05-30
Publication date: 2018-11-30

Abstract

Systems, curling rocks, curling rock handles, and methods for tracking a curling rock or other play object are disclosed. The curling rock or play object has a data-collecting unit operable during movement to measure acceleration values, rotation values, time, or other parameters of the play object. A processor of the data-collecting unit wirelessly transmits one or more of these parameters, which are data indicative of player performance. Fields of play, such as a curling sheet, have devices which are activated by the play object during movement thereof. Each device upon being activated wirelessly emits an information signal indicative of at least a position of the device with respect to the field of play.

Description

CURLING ROCKS, HANDLES, AND SYSTEMS AND METHODS FOR TRACKING
PLAY OBJECTS
TECHNICAL FIELD
[0001] The application relates generally to curling and, more particularly, to objects used to play curling.
BACKGROUND

[0002] In the sport of curling, information is collected on the distance travelled, speed, and rotation of the curling stone or "rock" as it moves along the iced curling sheet.
Current measurement methods lack both accuracy and breadth. The information that is measured may not capture several key variables. Techniques for tracking other objects along a playing surface also have drawbacks.
SUMMARY

[0003] In one aspect, there is provided a system for tracking a curling rock on a curling sheet, comprising: at least one device fixedly attachable to the curling sheet to be aligned with a line of play of the curling sheet, the at least one device comprising a position transceiver operable to emit an activation signal upon the curling rock crossing the line of play; and a data-collecting unit mountable to the curling rock and being operable during at least movement of the curling rock, the data-collecting unit comprising: an accelerometer unit to measure acceleration values of the curling rock along at least one translational degree of freedom; a gyroscope unit to measure rotation values of the curling rock about at least one rotational degree of freedom; a processor in communication with the position transceiver, the accelerometer unit, and the gyroscope unit, to obtain the acceleration values from the accelerometer unit, the rotation values from the gyroscope unit, and the activation signal from the position transceiver, the processor being operable to wirelessly transmit the acceleration values and the rotation values, the processor being operable to wirelessly transmit data indicative of player performance upon receiving the activation signal; and a power source supplying electrical power to at least the accelerometer unit, the gyroscope unit, and the processor.

[0004] In another aspect, there is provided a system for tracking a curling rock on a curling sheet, comprising: at least one device attachable to the curling sheet to be aligned with a line of play of the curling sheet, the at least one device comprising a position transceiver operable to emit an activation signal upon the curling rock crossing the line of play; and a data-collecting unit mountable to the curling rock and being operable during at least movement of the curling rock, the data-collecting unit comprising: a processor in communication with the position transceiver to receive the activation signal therefrom and to wirelessly transmit a time signal indicative of a time when the curling rock crossed the line of play; and a power source supplying electrical power to at least the processor.

[0005] In another aspect, there is provided a curling rock, comprising: a rock body; a handle attached to the rock body; and a data-collecting unit fixedly mounted to one of the rock body and the handle, the data-collecting unit being operable during at least movement of the curling rock, the data-collecting unit comprising: an accelerometer unit to measure acceleration values of the curling rock along at least one translational degree of freedom; a gyroscope unit to measure rotation values of the curling rock about at least one rotational degree of freedom; an identification transceiver being operable to emit an identification signal comprising information on a player using the curling rock; a processor in communication with the identification transceiver, the accelerometer unit, and the gyroscope unit, to obtain the acceleration values from the accelerometer unit, the rotation values from the gyroscope unit, and the identification signal from the identification transceiver, the processor being operable to wirelessly transmit the acceleration values, the rotation values, and the identification signal; and a power source supplying electrical power to at least the accelerometer unit, the gyroscope unit, and the processor.

[0006] In another aspect, there is provided a curling rock handle, comprising:
a handle body including a grip portion and a mounting portion, the mounting portion being .
mountable to a curling rock; and a data-collecting unit fixedly mounted to one of the grip portion and the mounting portion of the handle, the data-collecting unit being operable during at least movement of the curling rock, the data-collecting unit comprising: an accelerometer unit to measure acceleration values of the curling rock along at least one translational degree of freedom; a gyroscope unit to measure rotation values of the curling rock about at least one rotational degree of freedom; an identification transceiver being operable to emit an identification signal comprising information on a player using the curling rock handle; a processor in communication with the identification transceiver, the accelerometer unit, and the gyroscope unit, to obtain the acceleration values from the accelerometer unit, the rotation values from the gyroscope unit, and the identification signal from the identification transceiver, the processor being operable to wirelessly transmit the acceleration values, the rotation values, and the identification signal; and a power source supplying electrical power to at least the accelerometer unit, the gyroscope unit, and the processor.

[0007] In another aspect, there is provided a method for collecting data about a curling rock displaceable along a curling sheet, comprising: measuring acceleration values of the curling rock about at least one translational degree of freedom during displacement along the curling sheet; measuring rotation values of the curling rock about at least one rotational degree of freedom during displacement along the curling sheet; and wirelessly transmitting the acceleration and rotation values from the curling rock upon the curling rock crossing a line of play of the curling sheet.

[0008] In another aspect, there is provided a curling performance system, comprising: a data-collecting unit mountable to a curling rock and being operable during at least movement of the curling rock along a curling sheet, the data-collecting unit comprising:
an accelerometer unit to measure acceleration values of the curling rock along at least one translational degree of freedom; a gyroscope unit to measure rotation values of the curling rock about at least one rotational degree of freedom; a processor in communication with the accelerometer unit and the gyroscope unit to obtain the acceleration values from the accelerometer unit and the rotation values from the gyroscope unit, the processor being operable to wirelessly transmit at least the acceleration values and the rotation values; and a power source supplying electrical power to at least the accelerometer unit, the gyroscope unit, and the processor; and a performance unit mountable to a curling broom, the performance unit having a display and a performance processor in communication with the processor of the data-collecting unit, the performance unit including at least one application stored in a memory of the performance processor and executable thereby to: receive the acceleration and rotation values from the processor of the data-collecting unit; analyse at least one of the acceleration values and the rotation values along at least one of the translational and rotational degrees of freedom, and generate data indicative of player performance; and output the data indicative of player performance to the display.

[0009] In another aspect, there is provided a method for collecting data about a curling rock displaceable along a curling sheet, comprising: tracking when the curling rock crosses a first line of play of the curling sheet; tracking when the curling rock crosses a second line of play of the curling sheet; determining at least a difference in time between when the curling rock crosses the first line and play and the second line of play; and wirelessly transmitting the difference in time from the curling rock; and receiving a wireless transmission of the difference in time from the curling rock to alert a player of the difference in time.

[0010] In another aspect, there is provided a method for communicating between a curling rock and a curling broom, the method comprising: measuring acceleration values of the curling rock about at least one translational degree of freedom;
measuring rotation values of the curling rock about at least one rotational degree of freedom; and wirelessly transmitting at least the acceleration and rotation values from the curling rock to the curling broom upon the curling rock crossing a line of play of the curling sheet, to display at least one of the acceleration and rotation values on the curling broom.

[0011] In another aspect, there is provided a system for tracking a play object on a field of play, comprising: a data-collecting unit mountable to the play object and being operable during at least movement of the play object, the data-collecting unit comprising a power source supplying electrical power to a processor, the processor being operable to continuously wirelessly transmit an activation signal; and a tracking array having a base and a plurality of transceivers connected to the base and spaced apart along the base, the base and the transceivers being positionable about the field of play, each transceiver being activated by the activation signal emitted by the play object during movement thereof, each transceiver upon being activated wirelessly emitting an information signal indicative of at least a position of the transceiver with respect to the field of play.

[0012] In another aspect, there is provided a method of tracking a play object on a field of play, comprising: wirelessly transmitting an activation signal from the play object while the play object is moving; and activating at least one transceiver underneath the field of play with the activation signal of the moving play object, the at least one transceiver upon being activated wirelessly emitting an information signal indicative of at least a position of the at least one transceiver with respect to the field of play.

[0013] In another aspect, there is provided a method of tracking a play object on a field of play, comprising: wirelessly transmitting an activation trigger while the play object is moving to impact the play object; and detecting the activation trigger with at least one transceiver underneath the field of play after the activation trigger has impacted the play object and rebounded therefrom, the at least one transceiver upon detecting the activation trigger wirelessly emitting an information signal indicative of at least a position of the at least one transceiver with respect to the field of play, and a time at which the activation trigger was detected.
BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Reference is now made to the accompanying figures in which:

[0015] Fig. 1A is a perspective view of a curling rock having a data-collecting unit, according to an embodiment of the present disclosure;

[0016] Fig. 1B is a perspective view of a curling rock handle having a data-collecting unit, according to another embodiment of the present disclosure;

[0017] Fig. 2 is a schematic view of the data-collecting unit of Figs. 1A and 1B;

[0018] Fig. 3 is a schematic view of a system for tracking the curling rock of Fig. 1A on a curling sheet;

[0019] Fig. 4 is a schematic view of curling performance system having a plurality of the curling rocks of Fig. 1A in combination with curling brooms;

[0020] Fig. 5A is a schematic view of a system for tracking a play object on a field of play, according to another embodiment of the present disclosure;

[0021] Fig. 5B is a schematic view of a system for tracking a play object with respect to a feature of a field of play, according to yet another embodiment of the present disclosure;

[0022] Fig. 6A is a schematic view of a system for tracking a play object on a field of play, according to another embodiment of the present disclosure;

[0023] Fig. 6B is a schematic view of transceivers of the system of Fig. 6A;

[0024] Figs. 6C to 6E show travel of a play object through the system of Fig.
6A;

[0025] Fig. 7A is a schematic view of the curling rock of Fig. 1A, shown disassembled;

[0026] Fig. 7B is a schematic perspective view of the curling rock handle of the curling rock shown in Fig. 7A; and

[0027] Fig. 8 is a schematic view showing an angle of a curling rock as it crosses a line of play of a curling sheet.
DETAILED DESCRIPTION

[0028] Fig. 1A illustrates a curling rock 10 or stone for collecting and transmitting data.
The data collected and transmitted can be analysed to provide information about the skills of the player using the curling rock 10. The curling rock 10 can therefore serve as a diagnostic or analytic tool for evaluating player performance.

[0029] The curling rock 10 is manipulated during use by a player such that it undergoes movement. The curling rock 10 has a rock body 11, which forms the corpus of the curling rock 10 and provides structure thereto. An outer surface 12 of the rock body 11, and in particular a bottom portion of the outer surface 12, is in contact with an iced curling sheet to displace the curling rock 10 along the curling sheet. The curling rock 10 also has a handle 13 which is gripped by the player to displace the curling rock 10. The handle 13 has a grip portion 13A attached to a mounting portion 13B which is mounted to, and removed from, the rock body 11. Once attached to the rock body 11, there is no relative movement between the handle 13 and the rock body 11. In the depicted embodiment, the rock body 11 also has an interior 14 which includes a solid inner core 14A.

[0030] The curling rock 10 has six degrees of freedom and is manipulated to be moved therein. More particularly, the curling rock 10 has three translational degrees of freedom in which it can be displaced, and three rotational degrees of freedom about which it can rotate. These degrees of freedom are more easily appreciated by referring to the curling rock's 10 own coordinate system, defined by three orthogonal axes of motion, namely an X axis, a Y axis, and a Z axis. The three translational degrees of freedom are displacement movements of the curling rock 10 along the X, Y, and Z axes. In the depicted embodiment, the X and Y axes define movement along a horizontal plane, and the Z axis is vertically oriented and defines movement in a vertical direction. The three rotational degrees of freedom are rotational movements about the X, Y, and Z
axes. In most instances, but not necessarily all, the curling rock 10 will be displaced only in the horizontal plane defined by the X and Y axes, and this plane will be parallel to the surface of the curling sheet. In most instances, but not necessarily all, the curling rock will rotate only about the Z axis while it is being displaced along the curling sheet.

[0031] Still referring to Fig. 1A, the curling rock 10 has a data-collecting unit 20 disposed within the interior 14 of the rock body 11. In the depicted embodiment, the data-collecting unit 20 is part of the solid inner core 14A of the rock body 11. The data-collecting unit 20 collects data related to the movement of the curling rock 10, and transmits the data to a separate and remote device or system so that it can be analysed to provide information on player performance. This movement data can vary, and the data is related to the displacement of the curling rock 10 about itself, through space, and in time. It will be appreciated that the data-collecting unit 20 can also be operational when the curling rock 10 is stationary.

[0032] The location of the data-collecting unit 20 within the curling rock 10 can vary.
For example, in the embodiment of Fig. 1A, the data-collecting unit 20 is fixedly secured in place within the interior 14 of the rock body 11 itself, as part of its inner core 14A. The inner core 14A is sized to receive the data-collecting unit 20, and may include a cavity for receiving the data-collecting unit 20 which can be secured to the sides or floor of the cavity with an adhesive or a mechanical fastener. The fixed relationship between the data-collecting unit 20 and the inner core 14A ensures that there is no relative movement between the data-collecting unit 20 and the curling rock 10, thereby enabling the data-collecting unit 20 to directly measure the movement of the curling rock 10. For other types of curling rocks 10, there may not be a cavity, and the data-collecting unit 20 can be rigidly disposed within the rock body 11 using any other suitable technique.

[0033] In the embodiment of Fig. 1B, the data-collecting unit 20 is fixedly secured in place within the handle 13 of the curling rock 10, either within the grip portion 13A, the mounting portion 13B, or somewhere therebetween. The fixed relationship between the data-collecting unit 20 and the handle 13 ensures that there is no relative movement between the data-collecting unit 20 and the curling rock 10, thereby enabling the data-collecting unit 20 to directly measure the movement of the curling rock 10.

[0034] Figs. 7A and 7B show the curling rock body 11, handle 13, and data-collecting unit 20. In Fig. 7A, an underside of the curling rock 10 (i.e. the side facing the ice surface) is shown, along with a bolt 15 to insert into an aperture 17 extending through the curling rock body 11. The bolt 15 secures the handle 13 to a top surface of the curling rock 10. The data-collecting unit 20 in Figs. 7A and 7B includes a flexible PCB
which is removably attachable to an underside of the handle 13 with a gasket 19. A
power source 24 of the data-collecting unit 20 includes a non-contact rechargeable circuit, and the rechargeable circuit is operable to charge the power source via induction.

[0035] Referring to Fig. 2, the data-collecting unit 20 measures the movement of the curling rock 10 with one or more accelerometer units 21, and one or more gyroscope units 22. A processor 23 communicates with the accelerometer and gyroscope units 21,22 and transmits their measured values away from the curling rock 10 to a remote system or device for analysing the data. The power source 24 provides electrical power to each of the accelerometer unit 21, the gyroscope unit 22, and the processor 23. The power source 24 can be rechargeable. The power source 24 can be wirelessly rechargeable. Components of the data-collecting unit 20 are now discussed in greater detail.

[0036] The accelerometer unit 21 measures the movement of the curling rock 10 by generating its acceleration values along one or more of the three translational degrees of freedom. "Acceleration values" are understood herein to include acceleration vectors, as well as time derivatives/integrals of these values such as speed and displacement.
The acceleration values therefore have information on the direction of acceleration along any one of the X, Y, and Z axes, as well as the magnitude of acceleration. The accelerometer unit 21 outputs the acceleration values in units of distance per unit of time squared (e.g. in/s2, cm/52, ft/s2, m/s2, etc.). For example, it is possible to determine the velocity and speed of the curling rock 10, along any one of the X, Y, and Z axes, from the measured acceleration values. It is similarly possible to determine the distance travelled by the curling rock 10 along any one of the axes from the measured acceleration values. If the starting point of the curling rock 10 is known or determinable, the distance can be used to determine the displacement of the curling rock 10 along the iced curling sheet. It can thus be appreciated that the accelerometer unit 21 can be any device capable of such functionality, and typically includes an accelerometer and an associated memory or processor.

[0037] Still referring to Fig. 2, the accelerometer unit 21 samples or collects data constantly, at discrete time intervals. The accelerometer unit 21 generally measures the acceleration values at a relative high frequency. This sampling frequency can be in the range of 500 Hz to 2 kHz, for example, although other sampling frequencies are also within the scope of the present disclosure. The higher the sampling frequency, the more accurate the subsequent measurements will be, and hence the better the evaluation of player performance. The nature of the accelerometer unit 21 can also vary. For example, the accelerometer unit 21 is a "low g" accelerometer unit 21, meaning that it is capable of measuring lower accelerations values in the order of tens of "g".
It will be appreciated that other "g" values are within the scope of the present disclosure, and that the accelerometer unit 21 may have multiple accelerometer units 21, of both the high or low "g" types.

[0038] The gyroscope unit 22 measures the movement of the curling rock 10 by producing its rotation values about one or more of the three rotational degrees of freedom. "Rotation values" are understood herein to include measurements of the rotation or "spin" of the curling rock 10, as well as time derivatives/integrals of these values. The rotation values include information on the direction of rotation about any one of the X, Y, and Z axes, as well as the magnitude of rotation. For example, it is possible to determine the angular velocity or speed, as well as the revolutions per minute (RPM) of the curling rock 10, about the Z axis from the rotation values. The gyroscope unit 22 outputs the rotation values in units of angular displacement per unit of time (e.g. deg/s, rad/s, etc.).

[0039] Still referring to Fig. 2, the gyroscope unit 22 samples or collects data constantly, at discrete time intervals. The gyroscope unit 22 can measure the rotation values at a relative high frequency, an example of which is the range of about 500 Hz to about 1 kHz. This helps to ensure a high granularity of rotation values generated by the gyroscope unit 22 and transmitted by the curling rock 10. A lower capacity gyroscope unit 22, such as one that can measure rotations in the order of hundreds of deg/s, may also be used. It will therefore be appreciated that other "deg/s" values are within the scope of the present disclosure, and that the data-collecting unit 20 may have more than one gyroscope unit 22, of the both the high and low capacity types.

[0040] Both the accelerometer and gyroscope units 21,22 may collect movement data along one or more of the X, Y, and Z axes. Both the accelerometer and gyroscope units 21,22 can also be instructed to not generate data along/about the axis in question. This can also involve having the processor 23 ignore the data collected related to the axis in question, or to not transmit the data from this axis. Disregarding data from one or more axes may reduce data transmission and analysis delays.

[0041] The data-collecting unit 20 can have other sensors. In an embodiment, the data-collecting unit 20 has a temperature sensor and a humidity sensor. The temperature sensor generates temperature values, and the humidity sensor generates humidity values. The temperature and humidity sensors are operable to locally measure the temperature and humidity of the environment surrounding the curling rock 10 as it moves along the curling sheet. The temperature and humidity sensors are therefore able to capture changes in temperature and humidity along the curling sheet between precise locations thereof. The temperature sensor can include a thermometer, and the humidity sensor can include a hygrometer.

[0042] The processor 23 communicates with the accelerometer unit 21 and with the gyroscope unit 22, and other sensors, and obtains from them the acceleration values and the rotation values. The processor 23 then transmits the acceleration and rotation values at discrete time intervals to a system or device which analyses this data. In the depicted embodiment, the processor 23 does not analyse the acceleration and rotation values. In an alternate embodiment, the processor 23 performs data analysis itself. In the embodiment where the data-collecting unit includes a temperature sensor and a humidity sensor, the processor 23 also transmits the temperature and humidity values to a system or device which analyses this data. The processor 23 may therefore be any device that can collect and transmit data. Some non-limiting examples of the processor 23 include a microcontroller, a central processing unit (CPU), a front-end processor, a microprocessor, a graphics processing unit (GPUNPU), a physics processing unit (PPU), a digital signal processor, and a network processor. The processor 23 may also be part of a flexible PCB, which would allow the data-collecting unit 20 to match a curvature of the rock body 11 and/or handle 13.

[0043] Still referring to Fig. 2, the processor 23 transmits the acceleration and rotation values wirelessly. The transmission of the values is generally performed with a transmitting unit 25, such as an antenna or transceiver, to a remote device or network.
In some embodiments, the transmitting unit 25 is a BluetoothTM transmitter using low energy technology with a minimal transmission frequency (i.e. the frequency at which the transmitting unit 25 transmits the acceleration and rotation values).

[0044] In the embodiment of Fig. 2, the data-collecting unit 20 includes an identification transceiver 26. The identification transceiver 26 is operable emit an identification signal discretely, or at periodic intervals. The identification signal includes information related to the identity of the player using the curling rock 10. Some non-limiting examples of information included in the identification signal include the name of the player, the player's number, the player's team, the sex of the player, and the player's age. The processor 23 is operable to wirelessly transmit the identification signal away from the curling rock 10 for analysis and processing. The identification transceiver 26 may also receive signals, so as to be programmed or reprogrammed with information identifying the player and the curling rock 10 s/he will be using. The combination of the curling rock and identification transceiver 26 allows for the automatic identification of any player performing the action on the curling rock 10. In an alternate embodiment, the data-collecting unit 20 does not include the identification transceiver 26.

[0045] Referring to Fig. 3, there is disclosed a system 100 for tracking the curling rock 10 as it is displaced along the curling sheet 110. The curling sheet 110 is typically a substantially planar ice surface along which the players and the curling rocks 10 move.
The curling sheet 110 has multiple lines of play 120. Each line of play 120 is an elongated marking on the curling sheet 110. The curling rock 10 will often pass one or more lines of play 120 while it glides along the surface of the curling sheet 110 after it has been released by a player. Fig. 3 shows only about half the length of the curling sheet 110. The lines of play 120 shown in Fig. 3 include a back line 120A, a tee line 120B, a hog line 120C, and part of the centreline 120D. The back, tee, and hog lines 120A,120B,120C extend in a direction that is transverse to a direction of travel D of the curling rock 10 during normal curling play, while the centerline 120D is substantially parallel to the direction of travel D.

[0046] The system 100 incudes one or more of the data-collecting unit 20 described above. The data-collecting unit 20 is mountable to, and removable from, some portion of a corresponding curling rock 10, and is operable at least while the curling rock 10 is moving. The system 100 also includes one or more devices 130 that are attachable to the curling sheet 110. In the embodiment of Fig. 3, each device 130 is embedded within the ice of the curling sheet 110. In an alternate embodiment, each device 130 is removably mounted to the ice, or to some above-ice portion of the curling sheet 110.
Irrespective of how each device 130 is attached to the curling sheet 110, once so attached, the device 130 is in a fixed position and does not move. It is therefore suitably configured to track a movement of the curling rock 10 with respect to the device 130.

[0047] Each device 130 is aligned with one of the lines of play 120. The term "aligned"
is understood to mean that each device 130 is positioned with respect to a corresponding line of play 120 so that the device 130 can determine when a curling rock 10 has crossed the line of play 120. For example, and as shown in Fig. 3, each device 130 is embedded within the ice of the curling sheet 110 at both the tee line 120B
and the hog line 120C to track when the curling rock 10 crosses both lines 120B,120C.

In an alternate embodiment, each device 130 is affixed onto the ice of the curling sheet 110 above one or more lines of play 120.

[0048] Each device 130 includes a position transceiver 132. The position transceiver 132 in operation emits an activation signal when the curling rock 10 crosses the line of play 120 being monitored by the device 130. The activation signal includes information including, but not limited to, the time at which the curling rock 10 crossed the line of play 120, and the specific line (e.g. back line 120A, tee line 120B, hog line 120C, etc.) being monitored by the device 130. In the embodiment of Fig. 3, the position transceiver 132 becomes aware that the curling rock 10 has crossed the line of play 120 by receiving information from the curling rock 10. More particularly, the position transceiver 132 receives the identification signal emitted by the identification transceiver 26 to determine when the curling rock 10 has crossed the line of play 120. In an alternate embodiment, the curling rock 10 and its data-collecting unit 20 is passive. In such an embodiment, the data-collecting unit 20 does not emit any information that is readable by the position transceiver 132. Instead, the activation signal emitted by the position transceiver 132 impacts the curling rock 10 and is rebounded to the position transceiver 132 to thereby inform the position transceiver 132 that the curling rock 10 has crossed the line of play 120.

[0049] In the depicted embodiment, each position transceiver 132 is in a dormant state as a default condition, and is only "awoken" or activated when it receives the activation signal from the data-collecting unit 20. This passive operation of the position transceivers 132 allows the device 130 to be free of any power source. All energy required for the operation of the position transceivers 132 is provided by the activation signal. Depending on the strength of the activation signal (e.g. low-frequency, high-frequency, or ultra-high-frequency) the distance over which the activation signal can be received can vary from a few centimeters to a few meters or more.

[0050] The system 100 of Fig. 3 operates as follows. At least one device 130 is aligned with the tee line 120B, and at least one device 130 is aligned with the hog line 1200. As the player displaces the curling rock 10 along the direction D, the position transceiver 132 of each device 130 will emit the activation signal when the curling rock 10 crosses the tee line 120B and the hog line 1200. The activation signal in the depicted embodiment is received by the processor 23 of the data-collecting unit 20 of the curling rock 10. The processor 23 uses the information of the activation signal (e.g.
the time at which the curling rock 10 crossed the tee and hog lines 1206,120C), and with or without the acceleration and/or rotation values, can generate data indicative of player performance. An example of the data indicative of player performance that the processor 23 may generate includes data on the time that it takes the curling rock 10 to travel between the tee and hog lines 120B,120C, which may be an important player performance indicator. The processor 23 in such a configuration wirelessly emits a time signal in response to receiving the activation signal from the device 130. The time signal is indicative of a moment when the curling rock 10 crossed the corresponding line of play 120. In an alternate embodiment, each position transceiver 132 emits the activation signal to a remote server or computing device which also receives the acceleration and rotation values to generate the data indicative of player performance.

[0051] The processor 23 can also generate other data indicative of player performance.
Another example of the data indicative of player performance that the processor 23 may generate includes data on the rotation of the curling rock 10 when it crosses one of the lines of play 120. Yet another example of the data indicative of player performance that the processor 23 may generate includes data on the acceleration undergone by the curling rock 10 after it has been thrown and while it slides along the curling sheet 110 to determine friction from the curling sheet 110. Since it is possible for the data-collecting unit 20 to know the mass of the curling rock 10 or to be provided with such information, the processor 23 may emit data on a coefficient of friction of the ice surface at a specific location or along the path of travel of the curling rock 10. Yet another example of the data indicative of player performance that the processor 23 may generate includes data on the acceleration, and direction of travel along which, the player releases the curling rock 10 once it crosses one of the lines of play 120, to thereby generate data related to the player's skill in releasing the curling rock 10 without deviation. Yet another example of the data indicative of player performance that the processor 23 may generate includes data indicative of the "split time", which is the time it takes for the curling rock to travel between the back line 120A and the hog line 1200. The processor 23 in such a configuration therefore generates data indicative of the strength at which the player releases the curling rock 10. Yet another example of the data indicative of player performance that the processor 23 may generate includes the time at which the curling rock 10 crossed the line of play 120. When comparing players who release the curling rock 10 from the same line of play 120, it may be helpful to know the time at which the curling rock 10 crosses another line of play 120, in order to compare the performance of different players. Yet another example of the data indicative of player performance that the processor 23 may generate includes how far the curling rock 10 has deviated from a straight line path from its release at a line of play 120 to another location on the curling sheet 110, to thereby generate data related to the player's skill in releasing the curling rock 10 without left/right lateral drifting. Yet another example of the data indicative of player performance that the processor 23 may generate includes whether the player is pushing or pulling on the curling rock 10 at the moment of its release. Using acceleration values generated by the acceleration unit 21 in the moments leading up to the release of the curling rock 10, the processor 23 may generate data indicative of whether the player is holding back the curling rock 10, or giving it too much of a push.

[0052] The data indicative of player performance is wirelessly transmitted by the processor 23, via its identification transceiver 26 for example, to an object which is remote from the curling rock 10. The objet may take many forms. The object may be a remote server or computing device, such as a mobile computing device (e.g.
phone, tablet, laptop, etc.) which further analyses the data indicative of player performance, or displays the data indicative of player performance. The object may be a remote display, such as a scoreboard. The object may be a remote play object, such as a curling broom, which includes a display or alert to convey the data indicative of player performance to the player using the curling broom.

[0053] In the embodiment of Fig. 3, there is active/passive communication between the device 130 and the data-collecting unit 20. More particularly, the transmitting unit 25 of the processor 23 actively emits a signal, and the position transceiver 132 is operable to passively receive the signal from the processor 23. Stated differently, the passive component (i.e. position transceiver 132) does not actively search for the signal from the processor, and is instead energised by its receipt to emit the activation signal. In an embodiment, the position transceiver 132 has no electrical power source.
Examples of active/passive components that can be used as described above include a passive RFID tag (e.g. near field communication (NFC) tag) used with the position transceiver 132, and a RFID reader used with the processor 23.

[0054] Referring to Fig. 4, there is disclosed a curling performance system 200. The system 200 incudes one or more of the data-collecting unit 20 described above.
The data-collecting unit 20 is mountable to, and removable from, some portion of a corresponding curling rock 10, and is operable at least while the curling rock 10 is moving. The system 200 also includes a performance unit 210. The performance unit 210 collects and displays data indicative of player performance. Each performance unit 210 is associated with a curling broom 220. More particularly, each performance unit 210 is attachable to some part of the curling broom 220, and if desired, removable therefrom. The curling broom 220 is manipulated by a player (e.g. a "sweeper") against the ice of the curling sheet 110 to control the speed and direction of the curling rock 10 as it is displaced along the curling sheet 110. The system 200 may also include one or more of the devices 130 with the position transceivers 132 described above, which are fixedly attached to the curling sheet 110 to be aligned with one or more of the lines of play 120, and which are used to track a movement of the curling rock 10 with respect to the device 130, and with respect to the lines of play 120.

[0055] The performance unit 210 has a display 212 for providing the data indicative of player performance to the player manipulating the curling broom 220. The data can be provided in a visual, audio, or audiovisual format. In the embodiment of Fig.
4, the display 212 is a display monitor. The performance unit 212 also has a performance processor 214 which communicates with the processor 23 of the data-collecting unit 20 on the curling rock 10. The performance unit 210 may also include a suitable power source to provide electrical power to the display 212 and the performance processor 214.

[0056] The performance processor 214 contains a memory and one or more applications stored in the memory to be executed by the performance processor 214. In operation, the performance processor 214 receives the acceleration and rotation values generated by the data-collecting unit 20 of the curling rock 10 from the processor 23.
The performance processor 214 may also receive from the processor 23 the time that it takes for the curling rock 10 to travel between some of the lines of play 20, such as the "split time" described above. The processor 23 transmits at least one of the acceleration values, the rotation values, and the times measured between certain lines of play 120 wirelessly, such as via the transmitting unit 25 described above. The performance processor 214 analyse at least one of the acceleration values and the rotation values along at least one of their translational and rotational degrees of freedom to generate data indicative of player performance. The performance processor 214 outputs this data indicative of player performance to the display 212 so that the player manipulating the curling broom 220 becomes aware of the data in real time.

[0057] An example of the operation of the system 200 is now described. The skip of the curling team intends to release the curling rock 10 to have a specific "split time" and spin when the curling rock 10 leaves the hand of the skip at back line 120A.
The data-collecting unit 20 of the curling rock 10 generates the acceleration and rotation values, as well as the times it takes to cross the lines of play 120 by communicating with the device 130. The processor 23 transmits these values to the performance unit 210. The performance processor 214 analyses the acceleration values along the X-Y plane as well as the times received from the devices 130 to determine the "split time"
of the curling rock 10, and also analyses the rotation values about the Z axis to determine the angular speed or "spin" of the curling rock 10. The performance processor 214 outputs the measured "split time" and spin values to the display 212. The display 212 communicates the "split time" and spin values to the player manipulating the curling broom 220, either visually or by sound. The player manipulating the curling broom 220 is therefore aware of the "split time" and spin of the curling rock 10 as it crosses the hog line 120C, and based on this data indicative of player performance, can manipulate the curling broom 220 against the ice of the curling sheet 110 to control the speed and spin of the curling rock 10. It will be appreciated that the performance processor 214 may generate and output to the display 212 other data indicative of player performance.

[0058] Fig. 5A shows a system 300 for tracking a play object 310 on a field of play 311.
The system 300 helps determine the position of the play object 310 in real time on the field of play 311, or relative to a feature 312 of the field of play 311. In the embodiment of Fig. 5A, the play object 310 is a hockey puck, and the system 300 helps determine the position of the hockey puck on the ice surface of the field of play 311, or with respect to one of the line features 312 of the ice surface. "Field of play"
refers to a delimited or bounded space on which players can play a game or sport, regardless of the surface on which the players play. In alternate embodiments, the field of play 311 is a grass, wood, clay, or artificial surface. The feature 312 of the field of play 311 can also vary, and is not limited to the lines shown in Fig. 5A. It will also be appreciated that the play object 310 is not limited to the hockey puck of Fig. 5A. The play object 310 can include any other object used in sport or play that is manipulated by a player. Other embodiments of the play object 310 are described below.

[0059] The play object 310 includes a data-collecting unit 320, as described above. The data-collecting unit 320 in Fig. 5A includes a processor 323 powered by a power source 324 which provides electrical power to the processor 323. The data-collecting unit 320 may include other components, such as the accelerometer and gyroscope units mentioned above. The data-collecting unit 320 of the play object 310 is "active"
because it continuously and actively emits a signal. More particularly, the processor 323 is operable to wirelessly transmit an activation signal 322. As described in greater detail below, the activation signal 322 activates or energizes one or more components of the system 300 that are spaced apart from the play object 310. In the depicted embodiment, the processor 323 emits the activation signal 322 at all times, even when the play object 310 is stationary. In an alternate embodiment, the processor 323 emits the activation signal 322 only when the play object 310 is moving. In the depicted embodiment, the processor 323 emits the activation signal 322 at regular intervals of time. In an alternate embodiment, the processor 323 emits the activation signal 322 at irregular time intervals. The processor 323, and thus the play object 310, operates to actively emit a signal.

[0060] Still referring to Fig. 5A, the system 300 also includes a tracking array 330 for tracking the play object 310 along the field of play 311. In the depicted embodiment, the tracking array 330 includes a base 331 disposed underneath the ice surface of the field of play 311 (the base 331 is shown in dotted lines in Fig. 5A). In the depicted embodiment, the base 331 has a rectangular shape to conform to the portion of the ice surface under which it is disposed. In an alternate embodiment, such as the one described below, the base 331 has a different shape. In the depicted embodiment, the base 331 is pliable so that it can be folded or rolled for ease of deployment and storage.
In the depicted embodiment, the base 331 is in the form of a sheet or carpet that can be unrolled to cover the desired area underneath the ice surface.

[0061] The tracking array 330 also includes multiple transceivers 332 connected to the base 331 and also disposed underneath the ice surface field of play 311. The transceivers 332 are spaced apart along the base 331 and emit information to help track the play object 310 as it travels along the field of play 311. The transceivers 332 in the depicted embodiment are spaced apart to define a grid underneath the ice surface of the field of play 311. In an alternate embodiment, each transceiver 332 is implanted below the surface of the field of play 311 and the base 331 is a fragmented support for each transceiver 332. Other embodiments for connecting the transceivers 332 to the base 331 are also possible.

[0062] Still referring to Fig. 5A, each transceiver 332 is passively operated.
More particularly, each transceiver 332 is energized upon receiving the activation signal 322 emitted by the play object 310 moving in proximity to the transceiver 332. In the depicted embodiment, each transceiver 332 is in a dormant state as a default condition, and is only "awoken" or activated when it receives the activation signal 322 from the play object 310. This passive operation of the transceivers 332 allows the base 331 and indeed the tracking array 330 to be free of any power source. All energy required for the operation of the transceivers 332 is provided by the activation signal 322.
Depending on the strength of the activation signal 322 (e.g. low-frequency, high-frequency, or ultra-high-frequency) the distance over which the activation signal 322 can be received can vary from a few centimeters to a few meters or more.

[0063] Once activated, each transceiver 332 wirelessly emits an information signal 333 which is indicative of at least a position of the transceiver 332 with respect to the field of play 311. For example, an identification number is associated with each transceiver 332. The identification number is associated with specific coordinates on the ice surface (e.g. 17 cm, 24 cm). The information signal 333, upon being activated, may contain the identification number of the transceiver which is indicative of the position of the transceiver 332. As the play object 310 moves past different transceivers 332, the information signal 333 emitted by the activated transceivers 332 helps to map the trajectory of the play object 310 along the ice surface. The transceivers 332 can be any suitable device or take any suitable shape in order to achieve such functionality.

[0064] The information signal 333 is wirelessly transmitted by each activated transceiver 332 to an object which is remote from the field of play 311. The objet may take many forms. The object may be a remote server or computing device, such as a mobile computing device (e.g. phone, tablet, laptop, etc.) which further analyses the information signal 333 to generate a map of the trajectory of the play object 310, or displays the information signal. The object may be a remote display, such as a scoreboard or computing device.

[0065] An example of the tracking of the hockey puck play object 310 along the ice surface of the field of play 311 is now described with reference to Fig. 5A.
As the hockey puck moves along the ice surface, it emits the activation signal 322.
When the hockey puck passes over one of the transceivers 332 underneath the ice surface in sufficient proximity thereto, the activation signal 322 from the hockey puck will activate the transceiver 332 such that it will emit the information signal 333. In the depicted embodiment, the information signal 333 includes the coordinates of the transceiver 332 on the ice surface. In the depicted embodiment, the transceiver 332A is operable to emit an information signal 333 with the coordinates "1:2", where "1" is the X
position of the transceiver 332A on the base 331, and "2" is the Y position of the transceiver 332A
on the base 331. Alternatively, the information signal 333 contains an identification number for the transceiver 332A that is associated with a specific location on the ice surface. Similarly, the transceiver 332B is operable to emit an information signal 333 with the coordinates "1:4", where "1" is the X position of the transceiver 332B on the base 331, and "4" is the Y position of the transceiver 332A on the base 331.
It will be appreciated that each transceiver 332 has a unique set of coordinates on the base 331.
When the system 300 receives the coordinates from the transceivers 332A,332B, it will determine that the hockey puck has travelled between the transceivers 332A,332B a distance in the Y direction of 3 units. By also determining the difference in time between when the system 300 received the information signals 333 from the transceivers 332A,332B, the system 300 is also able to determine the average speed at which the hockey puck travelled between the transceivers 332A,332B. It will be appreciated that the information signal 333 may contain other information on the transceiver 332, and is thus not limited to only information on the position of the transceiver 332.

[0066] Still referring to Fig. 5A, another example of the operation of the system 300 is described. Transceivers 332C,332D,332E are located directly underneath the goal line 312A of the ice surface. The transceivers 332C,332D,332E operate to detect if the hockey puck has crossed the goal line 312A, and thus, whether a goal has been scored. As the hockey puck moves past the goal line 312A, its activation signal 322 will energise one or more of the transceivers 3320,332D,332E. The transceivers 332C,332D,332E which are activated by the activation signal 322 will emit the information signal 333 indicating their position on the ice surface. The system 300, upon receiving the one or more information signals 333, will be able to determine if and when the hockey puck has crossed the goal line 312A. The information signal in the depicted embodiment includes a logic or binary signal indicative of whether the hockey puck has or has not crossed the goal line 312A.

[0067] In the embodiment of Fig. 5A, there is therefore active/passive communication between the play object 310 and the tracking array 330. More particularly, the processor 323 of the play object 310 actively emits a signal, and the transceivers 332 are operable to passively receive the signal from the processor 323. Stated differently, the passive component (i.e. transceivers 332) does not actively search for the signal from the processor 323, and is instead energised by its receipt to emit the information signal 333. In an embodiment, the transceiver 332 has no electrical power source.
Examples of active/passive components that can be used as described above include a passive RFID tag (e.g. near field communication (NFC) tag) used with the transceivers 332, and a RFID reader used with the processor 323.

[0068] Fig. 6A shows another embodiment of the system 400 for tracking a play object 410 on a field of play 411. The system 400 operates similarly to the system described above, and therefore similar components and their reference numbers are incorporated by reference in the following paragraphs and will not be described again herein. In the embodiment of Fig. 6A, the play object 410 is a curling rock, and the system 400 helps determine the position of the curling rock on the ice surface curling sheet field of play 411, or with respect to one of the line features 412 of the curling sheet.

[0069] The data-collecting unit 420 of the curling rock 410 is "active"
because it continuously and actively emits a signal. i.e., the activation signal 422. The tracking array 430 includes the base 431 disposed underneath the curling sheet 411 (the base 431 is shown in dotted lines in Fig. 6A). In the depicted embodiment, the base 431 has a rectangular shape to conform to the portion of the curling sheet under which it is disposed. The base 431 is pliable so that it can be folded or rolled for ease of deployment and storage. In the depicted embodiment, the base 431 is in the form of a sheet or carpet that can be unrolled to cover the desired area underneath the curling sheet.

[0070] The transceivers 432 of the base 431 are disposed underneath the curling sheet. Fig. 6A shows that the transceivers 432 are disposed transversely across the curling sheet and all along its length. The transceivers 432 are spaced apart along the base 431 and emit information to help track the curling rock 410 as it travels along the curling sheet. The transceivers 432 in the depicted embodiment are spaced apart to define a grid underneath the curling sheet. Each transceiver 432 is passively operated, and is energized upon receiving the activation signal 422 emitted by the curling rock 410 moving in proximity to the transceiver 432. Once activated, each transceiver 432 wirelessly emits an information signal 433 which is indicative of at least a position of the transceiver 432 with respect to the curling sheet field of play 411. As the curling rock 410 moves past different transceivers 432, the information signal 433 emitted by the activated transceivers 432 helps to map the trajectory of the curling rock 410 along the curling sheet. Fig. 6B shows an example of the trajectory or travel path followed by the curling rock 410 along the curling sheet. More particularly, Fig. 6B shows the transceivers 432 which have been sequentially activated or energised by the curling rock 410 after it has travelled along the curling sheet.

[0071] An example of the tracking of the curling rock play object 410 along the ice surface of the curling sheet 411 is now described with reference to Figs. 60 to 6E. As the curling rock moves along the ice surface, it emits the activation signal 422, as shown in Fig. 6C. When the curling rock passes over one of the transceivers underneath the ice surface in sufficient proximity thereto, the activation signal 422 from the curling rock will activate the transceiver 432 such that it will emit the information signal 433, as shown in Figs. 60 and 6E. It will be appreciated that each transceiver 432 has a unique set of coordinates on the base 431. When the system 400 receives the coordinates from the transceivers 432, it will determine which transceivers 432 the curling rock has travelled over. By also determining the difference in time between when the system 400 received the information signals 433 from the transceivers 432, the system 400 is also able to determine the average speed at which the curling rock travelled between the transceivers 432.

[0072] Yet another example of the data indicative of player performance that may be generated includes the angle of travel or release of the curling rock 10 as it crosses one of the lines of play 120. Part of a player's skill in curling is determined by knowing whether the player released the curling rock 10 toward its intended target, such as the broom of another player for example, when the player pushed off to release the curling rock 10. This data indicative of player performance can be determined in different ways.

[0073] Referring to Fig. 8, the transceivers 432 of the base 431 are disposed underneath the curling sheet 110, and emit information to help track the curling rock 10 as it travels along the curling sheet 110. As the curling rock 10 is pushed by the player toward the line of play 120 at which the curling rock 10 will be released, the curling rock will pass over the transceivers 432 and energise them to produce a trajectory or travel path P followed by the curling rock 10 along the curling sheet 110 prior to its release. From this information, it is possible to determine the angle of release OR of the curling rock 10, which is defined between the travel path P of the curling rock 10 according to the transceivers 432, and a line perpendicular to the line of play 120, such as the centerline 120D. To determine the accuracy of the player's shot, the angle of release OR of the curling rock 10 may be compared to the target angle OT. A
line is defined between the point on the line of play 120 where the curling rock 10 crosses, and the target that the player is aiming for, in this example the curling broom 220 further down the curling sheet 110. The location of the curling broom 220 may be determined by prompting the performance processor 214 to emit a signal to energise one or more transceivers 432 underneath the curling broom 220. The target angle OT is the angle between this line and a line perpendicular to the line of play 120, such as the centerline 1200.

[0074] Another technique for determine the angle of release OR of the curling rock 10 relies on the components of the data-collecting object 20. The acceleration values produced by the accelerometer unit 21 provide the X and Y acceleration components of the curling rock 10 on the curling sheet when it is released at the line of play 120. From this information, it is possible to determine the hypotenuse, which corresponds to the travel path P along which the curling rock 10 is released. The angle of release OR of the curling rock 10 equals the angle formed between the hypotenuse and a line perpendicular to the line of play 120, such as the centerline 1200. In some instances, when determining the angle of release OR using this technique, it will be necessary to account for any rotation of the curling rock 10 when it is released. The gyroscope unit 22 of the data-collecting unit 20 is able to determine the initial angle of the curling rock 10, or some component thereof, at the time of the player pushing off the hack (i.e. the foothold device). To obtain the true angle of release OR it will be necessary in some instances to subtract the initial angle of the curling rock 10 or some component thereof (e.g. the handle 13) from the angle of release OR.

[0075] Although the techniques described above for determining the angle of release OR are explained with respect to releasing the curling rock 10 from one of the lines of play 120, it will be appreciated that these techniques may also be applied to determine the angle of release OR of the curling rock 10 when it is released from any point on the curling sheet 110.

[0076] Referring to Fig. 5B, another example of the operation of the system 300 is described. The play object 310 is a baseball and the feature 312 of the baseball field of play is a home plate 312B. In the depicted embodiment, the shape of the base (shown in dotted lines) disposed underneath home plate 312B is the same as the shape of home plate 312B. More particularly, the shape of the base 331 is a pentagon.
Transceivers 332F-332J are attached to the base 331 and located directly underneath the five corners of home plate 312B. The transceivers 332F-332J operate to detect if the baseball has crossed over the boundaries of home plate 312B, and thus, whether the pitcher has thrown a strike. As the baseball moves over home plate 312B, its activation signal 322 will energise one or more of the transceivers 332F-332J.
The transceivers 332F-332J which are activated by the activation signal 322 will emit the information signal 333 indicating their position on home plate 312B. The system 300, upon receiving the one or more information signals 333, will be able to determine if and when the baseball crossed over home plate 312B, and thus, whether a strike was thrown. The system 300 in Fig. 5B therefore allows for the automatic detection of strikes.

[0077] In sports or games where the play object 310 travels in the air above the field of play 311, the system 300 can help determine a third dimension of travel of the play object, i.e. its height above the field of play 311. This may be important in baseball, for example, where the strike zone is defined by the X-Y coordinates of home plate 312B, but also by the Z coordinate perpendicular to the X-Y plane of home plate 312B. Still referring to Fig. 5B, in an example, the baseball passes directly over the transceivers 332F and 332J. When the baseball travels over the transceiver 332F, the system 300 is able to determine the time it took the activation signal 322 emitted by the baseball to cause the emission of the information signal 333 from the transceiver 332F.
Knowing the speed of travel of the activation signal 322 from the baseball to the transceiver 332F
(e.g. speed of light or sound), also known as the "time of flight" of the activation signal 332, the system 300 can determine the distance in the Z axis of the baseball over the transceiver 332F, and thus, determine the height of the baseball over home plate 312B
at the corner under which the transceiver 332F is disposed. In a similar fashion, the system 300 is able to determine the height of the baseball over home plate 312B at the corner under which the transceiver 332J is disposed. This triangulation performed by the system 300 can thus accurately determine the height of the baseball over home plate 312B as it travels from one corner of home plate 312B to another. The system 300 is thus able to determine whether the baseball has travelled through the strike zone. In a particular embodiment, the strike zone is predefined with a vertical or height extent, such as for example starting at a lowermost height of about 50 cm above the surface of home plate to an uppermost height of about 150 cm above the surface of home plate.
Once the system 300 determines the height of the baseball over home plate 312B
at the corner under which the transceiver 332F is disposed, it can compare the height to the extent of the strike zone to determine whether the distance of the baseball above home plate 32B is between the lowermost height and the uppermost height of the strike zone.

[0078] Another configuration of the system 300 is now described with reference to Fig.
5B. In this configuration, the transceivers 332F-332J of the base 331 are active, and actively emit an activation trigger 322 as pulses of sound. The activation trigger 322 can be a signal or other electronic communication which causes data to be collected by the transceivers 332F-332J. The transceivers 332F-332J are also operable to detect and record reflections of the sound waves off of objects, such as the baseball. In this configuration, the home plate 312B is powered to power the transceivers 332F-332J so that they can emit the activation trigger 322. The home plate 312B in this configuration is provided with a suitable power source, such as a battery. The baseball may be passive such that it has no sensor or electronic component, or it may actively emit a signal as described above. One possible technique for determining the location of the baseball with respect to home plate 312B is now described. The transceivers 332J are operable to emit the activation trigger 322 as sound pulses, and to detect the reflected activation trigger 322 sound waves from the baseball. The system 300 knows when the activation triggers 322 were emitted, and also knows when the reflected activation triggers 322 are detected. The system 300 is thus able to determine the time it took for the activation trigger 322 to travel from the transceivers 332F-332J and to return to the transceivers 332F-332J after impacting the baseball. Knowing the speed of sound, the system 300 can determine the distance in the Z axis of the baseball over the transceivers 332F-332J, and thus, determine the height of the baseball over home plate 312B, and thus whether the baseball passed through the strike zone. This "time of flight" technique, which triangulates the position of the baseball with respect to home plate 312B, can thus accurately approximate the height of the baseball over home plate 312B as it travels over home plate 312B.

[0079] In a particular embodiment, the tracking of the baseball over home plate 312B is triggered by measurements made on the baseball by the system 300. As the pitcher throws the baseball, the velocity of the pitch is determined. Knowing the velocity of the pitch, the system 300 communicates with the transceivers 332F-332J and commands them to become active between a certain time interval during which the baseball is =
expected to cross over home plate 312B. For example, the speed of the pitch once the baseball is released by the pitcher would trigger the system 300 to command the transceivers 332F-332J that they should expect the baseball to first be over home plate 312B in about 0.3 seconds, and that the baseball will be expected to cross over home plate 312B for a total duration of 0.02 seconds. This embodiment of the system combines tracking the play object with information generated about the play object itself.

[0080] Another configuration of the system 300 is now described with reference to Fig.
5B. In this configuration, the transceivers 332F-332J of the base 331 are active, and actively emit an activation trigger 322 as a laser. The transceivers 332F-332J
or other sensors on home plate 312B are also operable to detect and record reflections of the light off of objects, such as the baseball. In this configuration, the home plate 312B is powered to power the transceivers 332F-332J so that they can emit the laser activation trigger 322. The may emit a vertical-cavity surface-emitting laser (VCSEL).
The sensors on home plate 312B are passive and are paired to the laser-emitting transceivers 332F-332J. The home plate 312B in this configuration is thus provided with a suitable power source, such as a battery, to power only the transceivers 332F-332J. The baseball in this configuration is passive such that it has no sensor or electronic component. One possible technique for determining the location of the baseball with respect to home plate 312B is now described. The transceivers 332F-332J are operable to emit the activation trigger 322 as lasers, and the passive sensors detect the reflected activation trigger 322 laser after they impact the baseball. The system 300 knows when the activation triggers 322 were emitted, and also knows when the reflected activation triggers 322 are detected. The system 300 is thus able to determine the time it took for the activation triggers 322 to travel from the transceivers 332F-332J and to return to the transceivers 332F-332J after impacting the baseball. Knowing the speed of light, the system 300 can determine the distance in the Z axis of the baseball over the transceivers 332F-332J, and thus, determine the height of the baseball over home plate 312B, and thus whether the baseball passed through the strike zone. This "time of flight" technique, which triangulates the position of the baseball with respect to home plate 312B, can thus accurately approximate the height of the baseball over home plate 312B as it travels over home plate 312B. This configuration of the system 300 may also combine tracking the play object with information generated about the play object itself, as described above.

[0081] The system 300 disclosed herein, in at least one of the configurations described, allows for placing an active emitter on the play object 310 and a passive receiver on the field of play 311. In contrast, some conventional systems have active receivers on the field of play and active emitters on a player, and thus require significantly more energy and coordination to determine the position of the player on the field of play.

[0082] The mention of curling rocks, brooms, and sheets above does not limit the systems disclosed herein to being used only in the sport of curling. The combination of the data-collecting unit 20 mounted to a play object and the performance unit 210 can be used in other sports and activities as well. For example, the play object can be a baseball, and the performance unit 210 can be attached to a play accessory that is a baseball glove. Similarly, the play object can be a golf ball, and the performance unit 210 can be attached to a play accessory that is a golf club. Similarly, the play object can be a bowling ball, and the performance unit 210 can be attached to a play accessory that is a bowling glove.

[0083] The above description is meant to be exemplary only, and one skilled in the art will recognize that changes may be made to the embodiments described without departing from the scope of the invention disclosed. Still other modifications which fall within the scope of the present invention will be apparent to those skilled in the art, in light of a review of this disclosure, and such modifications are intended to fall within the appended claims.

Claims

CLAIMS:

1. A system for tracking a curling rock on a curling sheet, comprising:
at least one device fixedly attachable to the curling sheet to be aligned with a line of play of the curling sheet, the at least one device comprising a position transceiver operable to emit an activation signal upon the curling rock crossing the line of play; and a data-collecting unit mountable to the curling rock and being operable during at least movement of the curling rock, the data-collecting unit comprising:
an accelerometer unit to measure acceleration values of the curling rock along at least one translational degree of freedom;
a gyroscope unit to measure rotation values of the curling rock about at least one rotational degree of freedom;
a processor in communication with the position transceiver, the accelerometer unit, and the gyroscope unit, to obtain the acceleration values from the accelerometer unit, the rotation values from the gyroscope unit, and the activation signal from the position transceiver, the processor being operable to wirelessly transmit the acceleration values and the rotation values, the processor being operable to wirelessly transmit data indicative of player performance upon receiving the activation signal; and a power source supplying electrical power to at least the accelerometer unit, the gyroscope unit, and the processor.

2. The system as defined in claim 1, wherein the at least one device is attachable underneath a surface of the curling sheet.

3. The system as defined in claim 1, wherein the at least one device is removably mountable adjacent to a surface of the curling sheet and above the surface of the ice sheet.

4. The system as defined in any one of claims 1 to 3, wherein the processor has a transmitting unit to actively emit a signal, and the position transceiver has a dormant default state and is only activated by the signal emitted by the processor.

5. The system as defined in claim 4, wherein the at least one device is free of a power source.

6. The system as defined in any one of claims 1 to 5, wherein the processor includes an identification transceiver being operable to emit an identification signal comprising information on a player using the curling rock.

7. The system as defined in claim 6, wherein the identification signal includes at least one of a name of the player, a number of the player, a team of the player, a sex of the player, and an age of the player.

8. The system as defined in any one of claims 1 to 7, wherein the activation signal includes at least one of the following: a time at which the curling rock crossed the line of play, an identification of the line of play, and a position coordinate of the at least one device on the curling sheet.

9. The system as defined in any one of claims 1 to 8, wherein the activation signal emitted by the position transceiver of the device includes at least a time at which the curling rock crossed the line of play, the data indicative of player performance emitted by the processor upon receiving the activation signal being the time at which the curling rock crossed the line of play.

10. The system as defined in any one of claims 1 to 8, wherein the at least one device includes a first device fixedly attachable to the curling sheet to be aligned with a first line of play, and a second device fixedly attachable to the curling sheet to be aligned with a second line of play spaced apart from the first line of play along the curling sheet, the activation signal emitted by the position transceiver of each of the first and second devices including at least a time at which the curling rock crossed said line of play, the data indicative of player performance emitted by the processor upon receiving the activation signals being a duration of time taken by the curling rock to cross between the first and second lines of play.

11. The system as defined in claim 10, wherein the first line of play is a back line of the curling sheet, and the second line of play is a hog line of the curling sheet, the duration of time being a split time.

12. The system as defined in any one of claims 1 to 11, wherein the data indicative of player performance emitted by the processor is the rotation values of the curling rock when it crossed the line of play.

13. The system as defined in any one of claims 1 to 12, wherein the data indicative of player performance emitted by the processor is the acceleration values of the curling rock when it crossed the line of play.

14. The system as defined in claim 13, wherein the processor is operable to wirelessly transmit a coefficient of friction of the curling sheet calculated as a function of the acceleration values.

15. The system as defined in any one of claims 1 to 14, wherein the data indicative of player performance emitted by the processor is at least one of a direction of travel of the curling rock when it crossed the line of play and an angle of release of the curling rock when it crossed the line of play.

16. The system as defined in any one of claims 1 to 15, wherein the at least one device includes a first device fixedly attachable to the curling sheet to be aligned with a first line of play, and a second device fixedly attachable to the curling sheet to be aligned with a second line of play spaced apart from the first line of play along the curling sheet, the activation signal emitted by the position transceiver of each of the first and second devices including at least a position coordinate of the first or second device on the curling sheet and a time at which the curling rock crossed said line of play, the data indicative of player performance emitted by the processor upon receiving the activation signals being a velocity of the curling rock between the first and second lines of play.

17. The system as defined in any one of claims 1 to 16, wherein the power source includes a non-contact rechargeable circuit, the rechargeable circuit being operable to charge the power source via induction.

18. The system as defined in any one of claims 1 to 17, wherein the data-collecting unit includes a temperature sensor to measure temperature values of an environment surrounding the curling rock, and a humidity sensor to measure humidity values of the environment surrounding the curling rock.

19. A system for tracking a curling rock on a curling sheet, comprising:
at least one device attachable to the curling sheet to be aligned with a line of play of the curling sheet, the at least one device comprising a position transceiver operable to emit an activation signal upon the curling rock crossing the line of play; and a data-collecting unit mountable to the curling rock and being operable during at least movement of the curling rock, the data-collecting unit comprising:
a processor in communication with the position transceiver to receive the activation signal therefrom and to wirelessly transmit a time signal indicative of a time when the curling rock crossed the line of play;
and a power source supplying electrical power to at least the processor.

20. The system as defined in claim 19, wherein the at least one device is attachable underneath a surface of the curling sheet.

21. The system as defined in claim 19, wherein the at least one device is removably mountable adjacent to a surface of the curling sheet and above the surface of the ice sheet.

22. The system as defined in any one of claims 19 to 22, wherein the processor has a transmitting unit to actively emit a signal, and the position transceiver has a dormant default state and is only activated by the signal emitted by the processor.

23. The system as defined in claim 22, wherein the at least one device is free of a power source.

24. The system as defined in any one of claims 19 to 23, wherein the processor includes an identification transceiver being operable to emit an identification signal comprising information on a player using the curling rock.

25. The system as defined in claim 24, wherein the identification signal includes at least one of a name of the player, a number of the player, a team of the player, a sex of the player, and an age of the player.

26. The system as defined in any one of claims 19 to 25, wherein the activation signal includes at least one of the following: the time at which the curling rock crossed the line of play, an identification of the line of play, and a position coordinate of the at least one device on the curling sheet.

27. The system as defined in any one of claims 19 to 26, wherein the at least one device includes a first device fixedly attachable to the curling sheet to be aligned with a first line of play, and a second device fixedly attachable to the curling sheet to be aligned with a second line of play spaced apart from the first line of play along the curling sheet, the processor being operable to wirelessly transmit a duration of time taken by the curling rock to cross between the first and second lines of play.

28. The system as defined in claim 27, wherein the first line of play is a back line of the curling sheet, and the second line of play is a hog line of the curling sheet, the duration of time being a split time.

29. The system as defined in any one of claims 19 to 28, wherein the at least one device includes a first device fixedly attachable to the curling sheet to be aligned with a first line of play, and a second device fixedly attachable to the curling sheet to be aligned with a second line of play spaced apart from the first line of play along the curling sheet, the activation signal emitted by the position transceiver of each of the first and second devices including at least a position coordinate of the first or second device on the curling sheet and the time at which the curling rock crossed said line of play, the processor being operable to wirelessly transmit a velocity of the curling rock between the first and second lines of play.

30. The system as defined in any one of claims 19 to 29, wherein the power source includes a non-contact rechargeable circuit, the rechargeable circuit being operable to charge the power source via induction.

31. The system as defined in any one of claims 19 to 30, wherein the data-collecting unit includes a temperature sensor to measure temperature values of an environment surrounding the curling rock, and a humidity sensor to measure humidity values of the environment surrounding the curling rock.

32. The system as defined in any one of claims 19 to 31, wherein the data-collecting unit includes at least one of an accelerometer unit to measure acceleration values of the curling rock along at least one translational degree of freedom, and a gyroscope unit to measure rotation values of the curling rock about at least one rotational degree of freedom.

33. A curling rock, comprising:
a rock body;
a handle attached to the rock body; and a data-collecting unit fixedly mounted to one of the rock body and the handle, the data-collecting unit being operable during at least movement of the curling rock, the data-collecting unit comprising:
an accelerometer unit to measure acceleration values of the curling rock along at least one translational degree of freedom;
a gyroscope unit to measure rotation values of the curling rock about at least one rotational degree of freedom;
an identification transceiver being operable to emit an identification signal comprising information on a player using the curling rock;
a processor in communication with the identification transceiver, the accelerometer unit, and the gyroscope unit, to obtain the acceleration values from the accelerometer unit, the rotation values from the gyroscope unit, and the identification signal from the identification transceiver, the processor being operable to wirelessly transmit the acceleration values, the rotation values, and the identification signal; and a power source supplying electrical power to at least the accelerometer unit, the gyroscope unit, and the processor.

34. The curling rock as defined in claim 33, wherein the data-collecting unit includes a temperature sensor to measure temperature values of an environment surrounding the curling rock, and a humidity sensor to measure humidity values of the environment surrounding the curling rock.

35. The curling rock as defined in claim 33 or 34, wherein the identification signal includes at least one of a name of the player, a number of the player, a team of the player, a sex of the player, and an age of the player.

36. The curling rock as defined in any one of claims 33 to 35, wherein the processor is operable to not analyse the acceleration and rotation values.

37. The curling rock as defined in any one of claims 33 to 36, wherein the power source includes a non-contact rechargeable circuit, the rechargeable circuit being operable to charge the power source via induction.

38. A curling rock handle, comprising:
a handle body including a grip portion and a mounting portion, the mounting portion being mountable to a curling rock; and a data-collecting unit fixedly mounted to one of the grip portion and the mounting portion of the handle, the data-collecting unit being operable during at least movement of the curling rock, the data-collecting unit comprising:
an accelerometer unit to measure acceleration values of the curling rock along at least one translational degree of freedom;
a gyroscope unit to measure rotation values of the curling rock about at least one rotational degree of freedom;

an identification transceiver being operable to emit an identification signal comprising information on a player using the curling rock handle;
a processor in communication with the identification transceiver, the accelerometer unit, and the gyroscope unit, to obtain the acceleration values from the accelerometer unit, the rotation values from the gyroscope unit, and the identification signal from the identification transceiver, the processor being operable to wirelessly transmit the acceleration values, the rotation values, and the identification signal; and a power source supplying electrical power to at least the accelerometer unit, the gyroscope unit, and the processor.

39. The curling rock handle as defined in claim 38, wherein the data-collecting unit includes a temperature sensor to measure temperature values of an environment surrounding the curling rock, and a humidity sensor to measure humidity values of the environment surrounding the curling rock.

40. The curling rock handle as defined in claim 38 or 39, wherein the identification signal includes at least one of a name of the player, a number of the player, a team of the player, a sex of the player, and an age of the player.

41. The curling rock handle as defined in any one of claims 38 to 40, wherein the processor is operable to not analyse the acceleration and rotation values.

42. The curling rock handle as defined in any one of claims 38 to 41, wherein the power source includes a non-contact rechargeable circuit, the rechargeable circuit being operable to charge the power source via induction.

43. A method for collecting data about a curling rock displaceable along a curling sheet, comprising:
measuring acceleration values of the curling rock about at least one translational degree of freedom during displacement along the curling sheet;

measuring rotation values of the curling rock about at least one rotational degree of freedom during displacement along the curling sheet; and wirelessly transmitting the acceleration and rotation values from the curling rock upon the curling rock crossing a line of play of the curling sheet.

44. The method as defined in claim 43, wherein measuring the acceleration values and measuring the rotation values includes measuring the acceleration and rotation values using a data-collecting unit mounted to the curling rock.

45. The method as defined in claim 43 or 44, further comprising measuring at least one of a temperature and a humidity at separate locations on the curling sheet.

46. The method as defined in any one of claims 43 to 45, wherein wirelessly transmitting the acceleration and rotation values includes wirelessly transmitting an identification signal comprising information on a player using the curling rock, the identification signal including at least one of a name of the player, a number of the player, a team of the player, a sex of the player, and an age of the player.

47. The method as defined in any one of claims 43 to 46, further comprising measuring at least one of the following: a time at which the curling rock crossed the line of play, an identification of the line of play, and a position coordinate of the at least one device on the curling sheet.

48. The method as defined in any one of claims 43 to 47, wherein wirelessly transmitting the acceleration and rotation values includes wirelessly transmitting rotation values upon the curling rock crossing the line of play.

49. The method as defined in any one of claims 43 to 48, wherein wirelessly transmitting the acceleration and rotation values includes wirelessly transmitting a coefficient of friction of the curling sheet calculated as a function of the acceleration values.

50. The method as defined in any one of claims 43 to 49, wherein wirelessly transmitting the acceleration and rotation values includes wirelessly transmitting a direction of travel of the curling rock when it crossed the line of play.

51. The method as defined in any one of claims 43 to 50, wherein wirelessly transmitting the acceleration and rotation values includes wirelessly transmitting the acceleration and rotation values includes to a remote device, server, or processor.

52. A curling performance system, comprising:
a data-collecting unit mountable to a curling rock and being operable during at least movement of the curling rock along a curling sheet, the data-collecting unit comprising:
an accelerometer unit to measure acceleration values of the curling rock along at least one translational degree of freedom;
a gyroscope unit to measure rotation values of the curling rock about at least one rotational degree of freedom;
a processor in communication with the accelerometer unit and the gyroscope unit to obtain the acceleration values from the accelerometer unit and the rotation values from the gyroscope unit, the processor being operable to wirelessly transmit at least the acceleration values and the rotation values;
and a power source supplying electrical power to at least the accelerometer unit, the gyroscope unit, and the processor; and a performance unit mountable to a curling broom, the performance unit having a display and a performance processor in communication with the processor of the data-collecting unit, the performance unit including at least one application stored in a memory of the performance processor and executable thereby to:
receive the acceleration and rotation values from the processor of the data-collecting unit;

analyse at least one of the acceleration values and the rotation values along at least one of the translational and rotational degrees of freedom, and generate data indicative of player performance; and output the data indicative of player performance to the display.

53. The curling performance system as defined in claim 52, wherein the processor includes an identification transceiver being operable to emit an identification signal comprising information on a player using the curling rock.

54. The curling performance system as defined in claim 53, wherein the identification signal includes at least one of a name of the player, a number of the player, a team of the player, a sex of the player, and an age of the player.

55. The curling performance system as defined in any one of claims 52 to 54, further comprising at least one device fixedly attachable to the curling sheet to be aligned with a line of play of the curling sheet, the at least one device comprising a position transceiver operable to emit an activation signal upon the curling rock crossing the line of play, the activation signal including at least one of the following: a time at which the curling rock crossed the line of play, an identification of the line of play, and a position coordinate of the at least one device on the curling sheet.

56. The curling performance system as defined in claim 55, wherein the performance processor is in communication with the position transceiver of the at least one device, the at least one application stored in the memory of the performance processor being executable to receive the activation signal from the position transceiver, the data indicative of player performance outputted to the display being the time at which the curling rock crossed the line of play.

57. The curling performance system as defined in claim 55, wherein the at least one device includes a first device fixedly attachable to the curling sheet to be aligned with a first line of play, and a second device fixedly attachable to the curling sheet to be aligned with a second line of play spaced apart from the first line of play along the curling sheet, the data indicative of player performance outputted to the display being a duration of time taken by the curling rock to cross between the first and second lines of play.

58. The curling performance system as defined in claim 57, wherein the first line of play is a back line of the curling sheet, and the second line of play is a hog line of the curling sheet, the duration of time being a split time.

59. The curling performance system as defined in any one of claims 55 to 58, wherein the data indicative of player performance outputted to the display is the rotation values of the curling rock when it crossed the line of play.

60. The curling performance system as defined in any one of claims 55 to 59, wherein the data indicative of player performance outputted to the display is the acceleration values of the curling rock when it crossed the line of play.

61. The curling performance system as defined in claim 60, wherein the at least one application stored in the memory of the performance processor is executable to analyse the acceleration values and generate a coefficient of friction of the curling sheet.

62. The curling performance system as defined in any one of claims 55 to 61, wherein the data indicative of player performance outputted to the display is a direction of travel of the curling rock when it crossed the line of play.

63. The curling performance system as defined in any one of claims 55 to 62, wherein the at least one device includes a first device fixedly attachable to the curling sheet to be aligned with a first line of play, and a second device fixedly attachable to the curling sheet to be aligned with a second line of play spaced apart from the first line of play along the curling sheet, the activation signal emitted by the position transceiver of each of the first and second devices including the position coordinate of the first and second device on the curling sheet and the time at which the curling rock crossed said line of play, the data indicative of player performance outputted to the display being a velocity of the curling rock between the first and second lines of play.

64. The curling performance system as defined in any one of claims 52 to 63, wherein the power source includes a non-contact rechargeable circuit, the rechargeable circuit being operable to charge the power source via induction.

65. The curling performance system as defined in any one of claims 52 to 64, wherein the data-collecting unit includes a temperature sensor to measure temperature values of an environment surrounding the curling rock, and a humidity sensor to measure humidity values of the environment surrounding the curling rock.

66. A method for collecting data about a curling rock displaceable along a curling sheet, comprising:
tracking when the curling rock crosses a first line of play of the curling sheet;
tracking when the curling rock crosses a second line of play of the curling sheet;
determining at least a difference in time between when the curling rock crosses the first line and play and the second line of play; and wirelessly transmitting the difference in time from the curling rock; and receiving a wireless transmission of the difference in time from the curling rock to alert a player of the difference in time.

67. The method as defined in claim 66, wherein the first line of play is a back line of the curling sheet, and the second line of play is a hog line of the curling sheet, the difference in time being a split time.

68. The method as defined in claim 66 or 67, wherein determining at least the difference in time includes determining a velocity of the curling rock between the first and second lines of play.

69. The method as defined in any one of claims 66 to 68, wherein receiving the wireless transmission of the difference in time includes alerting the player with an audio alert, a visual alert, or an audiovisual alert.

70. The method as defined in any one of claims 66 to 69, wherein wirelessly transmitting the difference in time from the curling rock includes wirelessly transmitting the difference in time to a display on a curling broom.

71. A method for communicating between a curling rock and a curling broom, the method comprising:
measuring acceleration values of the curling rock about at least one translational degree of freedom;
measuring rotation values of the curling rock about at least one rotational degree of freedom; and wirelessly transmitting at least the acceleration and rotation values from the curling rock to the curling broom upon the curling rock crossing a line of play of the curling sheet, to display at least one of the acceleration and rotation values on the curling broom.

72. The method as defined in claim 71, further comprising measuring at least one of the following: a time at which the curling rock crossed the line of play, an identification of the line of play, and a position coordinate of the line of play.

73. The method as defined in claim 72, wherein wirelessly transmitting at least the acceleration and rotation values includes wirelessly transmitting the time at which the curling rock crossed the line of play to display the time on the curling broom .

74. The method as defined in claim 72, wherein wirelessly transmitting at least the acceleration and rotation values includes wirelessly transmitting a difference in the time at which the curling rock crossed two lines of play, and displaying the difference in the time on the curling broom.

75. The method as defined in claim 74, wherein the two lines of play are a back line of the curling sheet and a hog line, and the difference in time is a split time.

76. The method as defined in claim 74, wherein wirelessly transmitting the difference in the time includes wirelessly transmitting a velocity of the curling rock between the two lines of play, and displaying the velocity on the curling broom.

77. The method as defined in any one of claims 71 to 76, wherein wirelessly transmitting at least the acceleration and rotation values includes wirelessly transmitting a coefficient of friction of the curling sheet calculated as a function of the acceleration values.

78. The method as defined in any one of claims 71 to 77, wherein wirelessly transmitting at least the acceleration and rotation values includes wirelessly transmitting a direction of travel of the curling rock when it crossed the line of play.

79. The method as defined in claim 71 or 78, further comprising measuring at least one of a temperature and a humidity at separate locations on the curling sheet.

80. The method as defined in any one of claims 71 to 79, wherein wirelessly transmitting at least the acceleration and rotation values includes wirelessly transmitting an identification signal comprising information on a player using the curling rock, the identification signal including at least one of a name of the player, a number of the player, a team of the player, a sex of the player, and an age of the player.

81. A system for tracking a play object on a field of play, comprising:
a data-collecting unit mountable to the play object and being operable during at least movement of the play object, the data-collecting unit comprising a power source supplying electrical power to a processor, the processor being operable to continuously wirelessly transmit an activation signal; and a tracking array having a base and a plurality of transceivers connected to the base and spaced apart along the base, the base and the transceivers being positionable about the field of play, each transceiver being activated by the activation signal emitted by the play object during movement thereof, each transceiver upon being activated wirelessly emitting an information signal indicative of at least a position of the transceiver with respect to the field of play.

82. The system as defined in claim 81, wherein each transceiver has a dormant default state and is only activated by the activation signal emitted by the play object.

83. The system as defined in claim 81 or 82, wherein the information signal includes a position coordinate of the corresponding transceiver on the field of play.

84. The system as defined in claim 83, wherein the position coordinate includes at least one of an identification number of the corresponding transceiver, and an X
and a Y value of the corresponding transceiver on the field of play.

85. The system as defined in any one of claims 81 to 84, where the information signal includes a time at which the corresponding transceiver was activated by the activation signal.

86. The system as defined in any one of claims 81 to 85, wherein the tracking array is free of a power source.

87. The system as defined in any one of claims 81 to 86, wherein the base and the transceivers of the tracking array is disposed underneath the field of play.

88. The system as defined in any one of claims 81 to 87, wherein the base is a sheet, and is manipulable to be rolled up and unrolled.

89. The system as defined in any one of claims 81 to 88, wherein the transceivers are disposed on the base in a grid pattern.

90. The system as defined in any one of claims 81 to 89, wherein the activation signal is one of a pulse of sound or a laser.

91. The system as defined in any one of claims 81 to 90, wherein the base and the transceivers are positionable about a goal line of a hockey ice sheet.

92. The system as defined in any one of claims 81 to 90, wherein the base and the transceivers are positionable about a home plate of a baseball field.

93. A method of tracking a play object on a field of play, comprising:
wirelessly transmitting an activation signal from the play object while the play object is moving; and activating at least one transceiver underneath the field of play with the activation signal of the moving play object, the at least one transceiver upon being activated wirelessly emitting an information signal indicative of at least a position of the at least one transceiver with respect to the field of play.

94. The method as defined in claim 93, wherein activating the at least one transceiver underneath the field of play includes activating at least two transceivers being spaced apart from each other underneath the field of play with the activation signal of the moving play object, and wirelessly emitting the information signal including a time at which the corresponding transceiver was activated by the activation signal.

95. The method as defined in claim 94, further comprising measuring a difference between the time at which each of the at least two transceivers was activated by the activation signal.

96. The method as defined in claim 95, further comprising measuring a distance separating the at least two transceivers, and determining a velocity at which the play object moved between the at least two transceivers.

97. The method as defined in any one of claims 93 to 96, wherein activating the at least one transceiver underneath the field of play includes positioning the at least one transceiver underneath a goal line of a hockey ice sheet.

98. The method as defined in claim 97, wherein activating the at least one transceiver underneath the field of play includes wirelessly emitting the information signal including a binary signal indicative of whether the play object crossed the goal line.

99. The method as defined in any one of claims 93 to 98, wherein wirelessly transmitting the activation signal from the play object includes marking a time of transmission of the activation signal, and wherein activating at least one transceiver underneath the field of play includes marking a time of transmission of the information signal, the method further comprising measuring a difference between the time of transmission of the activation signal and the time of transmission of the information signal, and calculating a distance of the play object above the field of play.

100. The method as defined in claim 99, further comprising establishing a zone above the field of play having a lowermost height and an uppermost height, and determining whether the distance of the play object above the field of play is between the lowermost height and the uppermost height of the zone.

101. The method as defined in any one of claims 93 to 100, wherein wirelessly transmitting the activation signal from the play object includes actively wirelessly transmitting the activation signal, and wherein activating the at least one transceiver underneath the field of play includes activating the at least one transceiver only with the activation signal.

102. A method of tracking a play object on a field of play, comprising:
wirelessly transmitting an activation trigger while the play object is moving to impact the play object; and detecting the activation trigger with at least one transceiver underneath the field of play after the activation trigger has impacted the play object and rebounded therefrom, the at least one transceiver upon detecting the activation trigger wirelessly emitting an information signal indicative of at least a position of the at least one transceiver with respect to the field of play, and a time at which the activation trigger was detected.

103. The method as defined in claim 102, wherein detecting the activation trigger with at least one transceiver underneath the field of play includes activating at least two transceivers being spaced apart from each other underneath the field of play with the activation trigger of the moving play object.

104. The method as defined in claim 103, further comprising measuring a difference between the time at which each of the at least two transceivers was activated by the activation trigger.

105. The method as defined in claim 104, further comprising measuring a distance separating the at least two transceivers, and determining a velocity at which the play object moved between the at least two transceivers.

106. The method as defined in any one of claims 102 to 105, wherein detecting the activation trigger with the at least one transceiver underneath the field of play includes positioning the at least one transceiver underneath a goal line of a hockey ice sheet.

107. The method as defined in claim 106, wherein detecting the activation trigger with the at least one transceiver underneath the field of play includes wirelessly emitting the information signal including a binary signal indicative of whether the play object crossed the goal line.

108. The method as defined in any one of claims 102 to 107, wherein wirelessly transmitting the activation trigger includes marking a time of transmission of the activation trigger, and wherein detecting the activation trigger with the at least one transceiver underneath the field of play includes marking a time of transmission of the information signal, the method further comprising measuring a difference between the time of transmission of the activation trigger and the time of transmission of the information signal, and calculating a distance of the play object above the field of play.

109. The method as defined in claim 108, further comprising establishing a zone above the field of play having a lowermost height and an uppermost height, and determining whether the distance of the play object above the field of play is between the lowermost height and the uppermost height of the zone.