A method and system for determining whether a spherical element impacts with a component of a playing field, or arranged on or proximate thereto. The method includes acquiring images of a surveillance area of a field that covers at least part of said component, such as a delimiting perimeter line of a game area or a target, performing an approximate detection of an impact of a spherical element relative to that component or proximate thereto, with an object detection and recognition system that can discern when the detected object is indeed a spherical element, automatically selecting one of the images acquired for the same point in time and that includes the area where said impact has occurred, and analyzing the selected image to check if the spherical element has impacted or not with the component.

A soccer training system may include one or more rebound units, including: a base; at least one rebound surface and rat least one tunnel having a tunnel inlet and a tunnel outlet, the tunnel has a cross section larger than a soccer ball. The shape of the tunnel may be such that when the base is placed on the ground a soccer ball entering the inlet is directed towards the outlet. The system may further include one or more defense player simulation devices, including a stable body to be placed on a field; and at least one adjustable indicator located on the stable body. In operation the at least one adjustable indicator may be configured to provide game instructions to a user. The system may further include a controller configured to: control the at least one adjustable indicator to provide the game instructions to the user.

According to various embodiments, a training device for hockey players is disclosed herein. The training device includes a puck sorting system for holding and orienting hockey pucks. The puck sorting system includes a puck drum having bottom and side portions and configured to hold therein a plurality of hockey pucks. The bottom portion of the puck drum has rotatably mounted thereon a conical puck agitation device configured to orient the plurality of hockey pucks into a predefined position. The training device further includes a puck launching system attached to the puck sorting system. The puck launching system includes a sloped tube operable to receive oriented hockey pucks and convey hockey pucks to a puck launcher. The puck launcher is configured to shoot hockey pucks via a spinning launching wheel driven by a launching motor.

A system is provided for assessing heard injury criterion (HIC) by analyzing signals received from sensors of a sensor array to calculate an impact force on an impact area, determine the linear acceleration based on the impact force and mass of the wearer's head. HIC values are calculated within a variable duration sliding window across a time period within which an impact occurs based on the integral of linear acceleration for the time period of the window, to determine a maximal HIC which is converted to a biofeedback signal.

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 emitting light suitable for forming color different from the principal color if the impact meets threshold impact criteria such that the impact-dependent portion temporarily appears 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. Use of light emission to produce the temporary color change is advantageous because the changed color can be virtually any possible visible color.

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. The object subsequently leaves the object-contact area. The impact-dependent portion first appears as the changed color no more than 0.2 s after the object leaves the object-contact area.

A device including a deformable shell delimiting an inner space, and a resilient band suspended in the inner space and including two ends secured to the deformable shell. The band includes a piezoelectric material to generate an electric voltage under the effect of the deformation of the shell and two electrodes for collecting the voltage. An electronic circuit for processing the voltage is arranged on the resilient band and connected to the electrodes of the resilient band.

A variable-color region (106) extends to an exposed surface (102) at a zone (112) and normally appears along it as a principal color. The region responds to an object (104) impacting the zone sufficiently hard at an object-contact area (116) by providing an impact signal identifying a criteria-meeting area (1626) where threshold impact criteria are met. Responsive to the impact signal and possibly to supplemental impact criteria being met, a controller (1622) produces a representation of a print area (118) from a representation of the criteria-meeting area by smoothening its perimeter and provides an initiation signal designating a location in the zone for the print area such that it closely matches the object-contact area. An impact-dependent portion (138) of the region responds to the initiation signal and possibly to a tracking condition being met by temporarily appearing along the print area as changed color materially different from the principal color.

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 protective structure (242) lying at least partly between the zone and the impact-sensitive color-change structure. 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, typically via light emission, 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 protective structure materially protects the impact-sensitive color-change structure from being damaged by matter impacting, situated on, and/or moving along the zone.

A smart ball-machine uses artificial intelligence to train a player or to play with a player. For example, the ball-machine can adjust the tennis ball speed, topspin, bounce according to the player's successful ball return rate. The ball-machine can be preconfigured with a profile of a player. For example, the ball-machine may download a complete profile of a tennis player from a game recording, or may download a file with a customized profile of a player to train a player using the ball-machine. The ball-machine is equipped with a plurality of wheels, motors, and shafts to provide a fully customizable launch of one or more balls. For example, the ball can be launched from the machine from one side of a tennis court to another side of a tennis court with a variety of speeds, trajectories, topspin, bounce etc.