A golf club head comprises a forward portion, comprising a strike face, and at least one tracking marker, configured to be tracked by a launch monitor and permanently embedded in the forward portion. The at least one tracking marker comprises a retroreflective surface that is more retroreflective than the strike face.

Disclosed is a method, a device, a system and/or a manufacture of training utilizing a target comprising strike sectors and/or a mat comprising position sectors indicated to the user. In one embodiment, a method for combat training, athletic training, and workout includes determining a position sector ID from a training file associated with a position sector visually identified on a mat including a position detector. A strike sector ID is determined associated with a strike sector on a strike target capable comprising a strike detector and capable of receiving a strike from a human extremity. A first indicator signal is generated to communicate the foot placement to the user and a second indicator signal communicates the strike sector. A strike signal is received from the strike and/or a position signal is received from the foot placement on the mat. The user's strike and/or positioning performance may be assessed.

A variable-color region (106) of an information-presentation structure extends to an exposed surface (102) at a surface zone (112) and contains multiple variable-color cells (404), each extending to a part (406) of the zone. The cells normally appear along their parts of the zone as a principal color. Each cell that meets cellular threshold impact criteria in response to an object (104) impacting the zone at an object-contact area (116) temporarily becomes a criteria-meeting cell that temporarily appears along its part of the zone as changed color materially different from the principal color. A group of less than all the cells usually constitute criteria-meeting cells. The surface parts of the criteria-meeting cells form a print area (118) that closely matches the object-contact area in size, shape, and location. The color-change capability helps in making in/out calls in sports such as tennis.

An information processing system inclines processing circuitry that is configured to receive input data from a shock sensor which outputs data based on a shock on the shock sensor, and identify a target segment of time-series data that is output from a motion sensor that senses a motion of an object. The target segment includes a pre-shock portion that occurs before the shock event and a post-shock portion that occurs after the shock event, the shock event is recognized based on the data from the shock sensor.

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 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 component employs an electrode assembly (202) having a core layer (222) sandwiched between two electrode structures (224 and 226) for controlling the color change.

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.

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 closely matching print area (118) of the zone as changed color materially different from the principal color if the impact meets threshold impact criteria. Object-tracking apparatus (808) tracks movement of the object over the surface and provides an image-causing tracking impact signal when the object impacts the zone according to the tracking. An image-generating system (802, 842, 1152, or 1182) responds to at least the impact signal by generating a print-area vicinity image consisting of an image of the print area and adjacent area of the surface.

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. The color-change time duration of the impact-dependent portion temporarily appearing as the changed color is in a duration range established prior to the impact. A controller (602) responds to both the impact and subsequent external instruction (608) by controlling the impact-dependent portion so as to adjust the color-change duration subsequent to the impact.