A method and system for assessing heaviness of a swing in sport of tennis is disclosed. The system may display the calculated heaviness of a groundstroke in real-time. As the player hits ground strokes, the system will measure linear and rotational speed of the ball and calculate a heaviness value based on the physics of translational and rotational kinetic energy of the ball.

The present disclosure relates to systems and methods for elastic delivery, processing, and storage for wearable devices based on system resources. For example, a wearable apparatus may have at least one battery; at least one sensor configured to measure at least one property associated with a user of the wearable apparatus; at least one memory storing measurements from the at least one sensor and instructions; at least one transmitter configured to send data to a device remote from the wearable apparatus; and at least one processor configured to execute the instructions to: receive, from the at least one battery, an indicator of a charge; and based on the received indicator, sending a command to the at least one sensor to operate in a low-power mode or a high-power mode, the low-power mode having. a lower sampling rate than the high-power mode.

An exercise management device using a hula hoop having a device for measuring spinning direction and exercise amount includes: an annular body part; a sensor unit including a gyro sensor, an acceleration sensor, and a gravity sensor; a hula hoop including a control unit including a MICOM for receiving and analyzing a data value detected by the sensor unit to calculate and obtain exercise information, a communication unit having a Bluetooth chip for transmitting the exercise information or the data value, and a power unit for switching on/off the control unit; and a wireless communication device having a dedicated program for receiving the exercise information or the data value transmitted from the communication unit and displaying the exercise information.

A sports ball is configured to enhance detection of spin properties by radar. The ball includes a spherical body having a first reflectivity with respect to radiation generated by a radar to be used in detecting spin of the ball. In addition, the ball includes a plurality of markers. Each of the markers has a second reflectivity with respect to the radiation generated by a radar to be used in detecting spin of the ball. The second reflectivity is different from the first reflectivity. The markers are distributed on the ball so that every great circle extending around an exterior surface of the ball is within a distance d of a projection on the exterior surface of the ball of at least one of the markers. The distance d is less than a radius of the ball.

Sensors in a golf teeing booth are used to: detect that a ball has be driven and estimate a predicted ball landing point on a golf practice range. A mobile unmanned golf ball retrieval vehicle, sometimes referred to as a gofer, determines a precise ball location on the field and reports the results to a control system. The control system updates the golfer's score based on the determined precise ball location.

A liquid discharge head includes: an individual channel having an inlet and an outlet, the individual channel including: a nozzle, an upstream-side pressure chamber arranged between the inlet and the nozzle, a downstream-side pressure chamber arranged between the outlet and the nozzle, an upstream-side throttle channel connecting the inlet and the upstream-side pressure chamber, and a downstream-side throttle channel connecting the outlet and the downstream-side pressure chamber; a supply channel connected to the inlet and configured to supply liquid to the individual channel; a recovery channel connected to the outlet and configured to recover the liquid from the individual channel; an upstream-side actuator configured to apply pressure to the liquid inside the upstream-side pressure chamber; and a downstream-side actuator configured to apply the pressure to the liquid inside the downstream-side pressure chamber. The channel resistance of the downstream-side throttle channel is smaller than that of the upstream-side throttle channel.

A method for monitoring the motion of a sport ball that has been impacted by an individual during the course of an athletic activity includes the steps of a portable electronic device wirelessly receiving motion data from the sport ball, and the portable electronic device determining a point of impact based on the motion data, wherein the point of impact includes a location on a surface of the sport ball where the impact occurred.

A system for illustrating the flight of a sports ball includes a radar, an imager, and a controller. The imager is configured to image a moving sports ball. The controller is configured to (i) receive, from the imager, an image including the moving sports ball, (ii) receive, from the radar, radar data associated with the moving sports ball, (iii) determine, from the radar data, a portion of a trajectory of the moving sports hall, (iv) alter the image to illustrate the portion of the trajectory relative to the moving sports ball, and (v) output the altered image.

An apparatus includes an acquisition unit configured to acquire a measurement result of a golf swing motion, and a calculation unit configured to calculate a behavior of a shot by the golf swing motion. The measurement result includes a head speed, an incident angle, and a face angle at the time of striking. The behavior includes an initial speed, a vertical launch angle, and a back spin amount. The calculation unit calculates the behavior by substituting the head speed, the incident angle, and the face angle, all of which have been acquired by the acquisition unit, into a predetermined arithmetic formula having a plurality of variables including at least a head speed, an incident angle, and a face angle at the time of striking of a golf club head.

A golf launch monitor is configured to determine a flight characteristic of a golf ball. The golf launch monitor includes two low-speed cameras, a trigger device, and a processor. The trigger device is configured to detect a golf swing. The processor is configured to instruct, upon the trigger device detecting said golf swing, the first camera to capture the first ball image; instruct the second camera to capture the second ball image after a time interval, wherein the time interval is less than the first frame rate and the second frame rate; and determine, based at least in part on the first ball image and the second ball image, the flight characteristic of the golf ball.