A system for refereeing a sports match including a portable processing device for compiling data associated with the sports match and eyeglasses including data display means for displaying the data associated with the sports match to a wearer of the eyeglasses.

An Internet of Thing (IoT) sport device includes a body with a processor, a camera and a wireless transceiver coupled to the processor.

An Internet of Thing (IoT) device includes a body and sensors including a camera and an accelerometer; a processor; and a wireless transceiver coupled to the processor.

The present application is directed to an athletic training tool. The athletic training tool includes a ball and an elongated member attached thereto, the elongated member is attached to the ball in a manner effective to maintain the center of gravity of the ball. The elongated member may be visually observable during use of the athletic training tool.

A variable-color region (106) of an information-presentation structure extends to an exposed surface (102) at a surface zone (112), normally appears along it as a principal color, and includes impact-sensitive color-change structure (132) and duration-extension structure (242). A segment (142) of the impact-sensitive color-change structure responds to an object (104) impacting the zone at an object-contact area (116) by causing an impact-dependent portion (138) of the variable-color region to temporarily appear along a print area (118) of the zone as changed color materially different from the principal color if the impact meets threshold impact criteria. The print area closely matches the object-contact area in size, shape, and location. The duration-extension structure responds to the impact by causing the impact-sensitive color-change structure to deform along an internal deformation area (288). This causes the time duration of the impact-dependent portion appearing as the changed color to be controllably extended.

A variable-color region (106) of an information-presentation structure extends to an exposed surface (102) at a surface zone (112), normally appears along it as a principal color, and includes impact-sensitive and color-change components 182 and (184). A segment (192) of the impact-sensitive component responds to an object (104) impacting the zone at an object-contact area (116) by providing an impact effect if the impact meets threshold impact criteria. A segment (194) of the color-change component responds to the impact effect by causing an impact-dependent portion (138) of the variable-color region to temporarily appear along a print area (118) of the zone as changed color materially different from the principal color. The print area closely matches the object-contact area in size, shape, and location. The color-change capability helps, for instance, in making in/out calls in sports such as tennis.

A variable-color region (106) of an information-presentation structure extends to an exposed surface (102) at a surface zone (112) and normally appears along it as a principal color. An impact-dependent portion (138) of the variable-color region responds to an object (104) impacting the zone at an object-contact area (116) by temporarily appearing along a print area (118) of the zone as changed color materially different from the principal color if the impact meets threshold impact criteria. The print area closely matches the object-contact area in size, shape, and location. An image-generating controller (806) responds to the impact by causing an image-generating structure (804) to generate an image of the print area and adjacent surface extending to at least a selected location of the exposed surface if the threshold impact criteria are met. The image assists in determining how close the impact occurred to the selected surface location.

An Internet of Thing (IoT) device includes a camera coupled to a processor; and a wireless transceiver coupled to the processor. Blockchain smart contracts can be used with the device to facilitate secure operation.

A variable-color region (106) of an information-presentation structure extends to an exposed surface (102) at a surface zone (112) and normally appears along it as a principal color. An impact-dependent portion (138) of the variable-color region responds to an object (104) impacting the zone at an object-contact area (116) by temporarily appearing along a print area (118) of the zone as generic changed color materially different from the principal color. The print area closely matches the object-contact area in size, shape, and location. The threshold impact criteria consist of multiple sets of different threshold impact criteria respectively associated with multiple specific changed colors materially different from the principal color. If the impact meets the threshold impact criteria, the generic changed color is the specific changed color for the criteria set met by the impact.

A variable-color region (106) of a tennis-playing structure of an information-presentation structure extends to an exposed surface (102) at a surface zone (112), normally appears along it as a principal color, and includes impact-sensitive and color-change components (182 and 184). A segment (192) of the impact-sensitive component responds to an object (104), typically a tennis ball, impacting the zone at an object-contact area (116) by providing an impact effect if the impact meets threshold impact criteria. A segment (194) of the color-change component responds to the impact effect by causing an impact-dependent portion (138) of the variable-color region to temporarily appear along a closely matching print area (118) of the zone as changed color materially different from the principal color. The zone adjoins a serviceline (34), the centerline (36), a sideline (30), or a baseline (28) to help determine whether a tennis ball impacted the surface in or out.