Patent Application
20250073552
The present disclosure relates to systems and methods for teaching and increasing athletic performance due to access to crucial data necessary to provide a better understanding of the pressure exerted on a ball and as such, force, imparted upon a ball to create movement of a ball by an athlete.
Measurement of ball flight in sports is an important outcome of player actions. For example, the arc and spin of a basketball is indicative of a player's shooting motion; the motion of a golf ball or tennis ball is indicative of the contact conditions between the ball and club (or racquet) as well as the motion of the club (racquet) head at contact; a football's spin and flight path are a result of the quarterback's arm and hand motions and grip on the ball; and a baseball pitch's movement is dependent on release speed, direction and spin, as imparted by the pitcher. While movement of a pitcher's arms, legs, and hands generate the force that will drive the baseball, this force is ultimately imparted on the ball through only the player's fingers and finally fingertips.
For baseball and softball pitches in particular, the flight of the ball is particularly important. It is one of the key tools of a pitcher for misleading the batter and/or simply causing the batter to swing and miss the ball. Other than atmospheric conditions (e.g., wind, air temperature, density, and humidity), which are out of a pitcher's control, the path of a pitched ball is affected by release velocity (speed and direction in 3-dimensional space), release point (location in 3-dimensional space) and spin (rate and direction). During a theoretical free flight of a non-spinning ball, the ball is affected by two primary forces, drag and gravity. Gravity causes the ball to follow a curved path in the vertical direction according to Eq. 1:
where z(t) is the vertical position of the ball in space at any point in time, t is time elapsed from the moment of release, z0 is the vertical position at release, Vz is the vertical component of ball velocity at release, and g is the acceleration of gravity. The drag force is in the opposite direction of the ball's velocity, proportional to the square of the ball's velocity, and has the effect of reducing the ball's speed as it moves.
With a spinning ball, there is a third force, which is most relevant to the disclosure, called lift or more specifically the Magnus force. This lift force is produced by an effect caused by Bernoulli's Principle whereby the faster the air moves over a surface the pressure on that surface is reduced. The rate of air flow over the opposite sides of a spinning ball produces a differential in air speed which gives rise to an unbalanced force on the ball resulting in the Magnus force. The magnitude and direction of the Magnus force depends on a combination of spin rate, angle of spin axis, and ball speed.
In baseball, softball, tennis, and other sports, spin can be imparted upon the ball by the athlete. Backspin, which is predominately the spin imparted by a baseball pitcher for a fastball, creates a situation whereby air is moving faster on the top of the ball than the bottom of the ball allowing Bernoulli's Principle to provide lift or the Magnus force in an upward direction. As athletes become more accomplished, this applied spin is not always straight up and down vertically and as such, the Magnus force can create various movements upon the ball depending upon the angle of such force due to the spin angle.
As NASA's Glenn Research Center shows in their explanation of the lift on a spinning baseball, the lift (L, or Magnus force) on a spinning baseball (assuming atmospheric conditions remain constant) is equals:
where Cl is the coefficient of lift, b is the ball's radius, ρ is the density of air, V is the velocity, and s is the spin rate. Equation 2 shows that the magnitude of the Magnus force increases as the spin rate increases. Thus, as the pitcher imparts higher spin on the ball the Magnus force increases. This simplified equation assumes that the axis of spin rotation in perpendicular to gravity and as such the lift and gravitational forces are in directly opposite vertical directions.
In reality though, the axis of spin rotation will likely not be perpendicular to gravity due to the athlete's biomechanics and desire to create ball movement in various directions. Thus, the direction of the Magnus force can cause a ball in flight to move in various directions which is sometimes referred to as the “break” of the pitch.
By spinning a ball in a selected direction, the pitcher can cause the ball to break in any direction (up, down, or to either side horizontally) as it moves in 3-dimensional space toward home plate. For example, a “12-6 curve ball” has forward (top) spin, as opposed to backspin, which gives rise to a downward Magnus force and thus a downward break (more so than a ball thrown that falls only due to gravity); a fastball has backward spin, an upward Magnus force and therefore an upward break (actually pitchers cannot produce enough spin to cause the ball to rise, but it does not fall as fast as it would from the gravity force alone); and sliders and screwballs have horizontal break. In general, the Magnus force for most pitches is not strictly vertical or horizontal, so the break is in both horizontal and vertical directions simultaneously.
In summary, both direction and magnitude of the ball's spin after release affect its flight path so control of those metrics is important for a pitcher to perform effectively. It is generally desirable that a pitcher consistently control the direction of spin and maximize the spin rate applied to the ball.
Conventionally, pitch spin rate has been measured using fixed measurement systems that employ either radar or optical (for example, video, which can utilize the visual spectrum or beyond, such as infrared) analysis. One currently available commercial system called Rapsodo™ uses an optical method. That system measures pitch spin rate according to a fixed global reference frame and detects speed and direction of ball movement within that frame. Another currently available commercial tracking system (Trackman™) uses radar measurements at multiple locations to determine ball flight and spin information. In video analysis systems, image analysis can be used to ascertain the orientation of ball threads and the change in orientation with respect to time to determine both spin axis and rate. In addition, Diamond Kinetics, Inc. has developed and marketed a baseball that includes internal sensors and electronics to measure velocity, spin rate and angle plus communicate such data with handheld devices.
While such systems can provide accurate measurements and estimates of ball spin conditions (as well as measuring velocities and/or positions of other objects), they do not measure the pressures exerted upon the ball by the athlete's fingers to create the forces on the ball that are ultimately responsible for such movement and velocity. This is a critical data point in a number of sports. Additional and specialized data collection is therefore needed to provide these data points in order to implement them in practical player-improvement strategies.
For example, in baseball, a ball's movement may vary according to a number of well-known and documented factors including those in the following non-limiting and non-exhaustive list: spin rate and angle; biomechanics; the particular ball's size, geometry, and other physical attributes; atmospheric conditions; and the pressure and force specifically imparted on the ball prior to free flight. Many of these factors are external and may be measured using the above-mentioned conventional systems and means or systems similar thereto. However, the pre-flight pressure and force imparted to the ball require more specialized means of measurement.
While it is well known and documented that spin rate and angle, biomechanics, size, geometry and other physical attributes of the specific ball, and atmospheric conditions impact the flight of a ball, it is ultimately the pressure of a pitcher's fingers and the locations of those fingers on the ball that act as the primary mechanisms determining a baseball's movements. Pitcher's use their grip to produce different types of pitches. Each grip has its own unique finger position through which each finger exerts a different level of force on the baseball. Through the use of different finger positions and pressures, the pitcher can produce different axis of spin resulting in different types of pitches. There is a general understanding that certain finger positions will result in expected ball movements as shown in
This variance may derive from a pitcher's individual grip or biomechanics. As pressure is applied to the ball, friction arises between the pitcher's fingers and the ball's surface including its laces. It is worth noting that the amount of that friction is impacted by numerous factors including, but not limited to: (1) the height of a baseball's laces, which progressively lower in height from little league, high school, college, minor league (Rookie to AA), and major (AAA to MLB) baseball laces; (2) the slickness of the baseball's cover (an MLB baseball is the slickest) will reduce the friction an athlete can garner from his fingers; (3) any agent (such as Spider Tack) or fabric interface between a pitcher's fingers and the ball (such as a glove worn on the throwing hand); (4) and any other material/surface likewise disposed between the pitcher's fingers and the baseball. Each of these factors can change the coefficient of friction, and thus, spin rate imparted upon the baseball by the pressure imparted on the ball by the pitcher's fingers.
It is therefore critical to not only have dynamic, time-coded data related to the pressure and location of the athlete's fingers through the throwing motion (or other physical contact with the ball, such as in tennis or soccer) but also that this data be collected under conditions which substantially replicate those an athlete is likely to experience during a game. Although there exist certain conventional approaches to measuring similar data, there are deficiencies in these approaches that the present disclosure seeks to address.
Some conventional sensor systems include pressure sensors using individual discrete sensors, pads, or fabric to determine pressure from somewhat static environments to dynamic, quick moving scenarios including athletics. A classic visual example of a pressure sensing mat has aided many in the selection of the proper orthotic for their individual foot geometry and stance.
Other rigid and flexible pressure sensors exist for use in many applications from medical, to industrial, to athletic. Among these are those developed by Tekscan for use in insoles, golf grip measurement, concussion detection research, and hand and finger pressure and force measurement via gloves.
Similarly, other athletic pressure sensing technologies and applications have been developed by Moticon with a primary focus on insole applications with high-end motion analytics for objective insights enhancing athlete training and patient recovery. These sensor systems feature internal battery power and charging, pressure sensing mesh, data analysis, and communication.
When a baseball is pitched, the only pressure applied to the ball is from the pitcher's fingers. It is therefore essential to understand and measure that pressure as it is the key mechanism directly driving the ball's movement. It is likewise essential for any data to be relevant and useful that the pressure be measured under substantially real-world and in-game conditions. As discussed above, to throw a baseball with control, accuracy, velocity, and movement, a pitcher needs to have a true tactile connection with the baseball. In other words, there needs to be a direct interface between the skin of the player's fingers with the surface of the ball. When throwing the baseball, the pitcher must feel the leather and the seams below his fingers to produce the pitch he wants to throw, and he trains to perfect such a consistent feeling. Further, to accurately monitor and measure a player's performance as would be expected in a game, the conditions during training should mirror those experienced in a game.
While conventional gloves with embedded sensors can certainly measure pressure, any measured pressure data will not reflect the “in game” conditions or facilitate the accurate study, or improvement, of a pitcher's technique. This is in part because using the sensor-embedded glove deviates from a pitcher's tactile experience when pitching during standard play. It changes the expected tactile feel of the baseball which will impact a pitcher's performance. Moreover, as the surfaces in direct contact have changed (the glove being in direct contact the ball's surface rather than the skin of the player's hand), the coefficient of friction is also different. This change in the coefficient of friction will effectively render any observational data gathered in parallel through external apparatus (such as Trackman systems) useless as any observed causal relationship between pressure and such externally collected data would not accurately reflect the causal relationship present in real world, in-game conditions. Put another way, the ball's flight path, speed, and spin rate as measured by the external systems would not reflect the trajectory of the same ball if thrown with the same pressure applied to the same locations on the ball by the same pitcher who was not wearing a glove on their throwing hand. Using conventional systems, there is simply no way to both observe a baseball's flight dynamics when thrown under real-world, in-game conditions and to measure the specific pressures applied to that baseball by the pitcher to produce the observed pitch.
Although unsuitable for the more comprehensive data collection and analysis discussed above, conventional, sensor-embedded gloves can be used for data acquisition in sports such as golf and football since the connection between athlete and equipment has a different tactile necessity and desire. For example, a football receiver has less of a requirement for a feeling on specific fingers and desires a high coefficient of friction to aid in his catching of a spinning football approaching him with velocity. Additionally, many players in other sports such as golf or football may wear a glove during normal play.
Accordingly, there is a need for a specialized system, and related specialized methods, to measure and process data in conditions substantially identical to those experienced during normal circumstances or play. Conventional sensor configurations and systems are simply insufficient to meet this need.
The present disclosure is directed to systems and methods for measuring pressures exerted by a pitcher, bowler, or other thrower on a ball with pressure sensing means disposed within the ball. While the present disclosure can relate to any freely spinning object with the equipped sensors and electronics, of particular interest are sports balls and objects that experience free flight as a result of being thrown, hit, or kicked, such as baseballs, softballs, basketballs, footballs, soccer balls, cricket balls, tennis balls, and other moving balls and objects.
In accordance with the present disclosure, a system for determining pressure and location of such pressure(s) prior to free flight includes a pressure sensor assembly and a processing assembly wherein both the sensor assembly and processing assembly may be embedded in the ball. Optionally, the processing assembly may comprise a first and second processing unit, wherein said second processing unit is an external device (including a computer, mobile phones, tablets, or other devices), that is communicably coupled to the first processing unit embedded in the ball.
The pressure sensor assembly may provide data (such as voltage data) to the processing assembly signifying that amount of pressure being applied. A pressure sensor assembly may include multiple discrete sensors placed within the ball at specific locations; a fabric or mesh sensor; or some combination thereof. With any of these embodiments, the pressure sensor assembly may be configured to transmit sensor activity data geocoded with the location of the activity. The data from the pressure sensor assembly may be segmented to selected events and times of interest for the object, such as, in baseball, pitcher gripping the ball, releasing from glove or “break”, pre-release, and release for free flight start, etc. or, in soccer, as pre-kick, initial foot-ball contact, and free flight start, etc.
Preferably, the processing assembly of the present disclosure includes one or more microcontrollers that manage and execute data acquisition, data computation, power management, and communication processes that are associated with data that is generated by the pressure sensor assembly. Also, the processing assembly may include a wireless communication module that can send raw data generated to the pressure sensor assembly or data that is processed to the processing assembly.
In embodiments of the present disclosure, the time and location coded data representing sensor activity can be received by the processing assembly and stored therein for later communication. The processing assembly may process this data into time and located-coded pressure data. In other embodiments, raw time and location coded data can be processed by the second processing unit that is in communication with the first processing unit and capable of processing data generated by the sensor assembly.
In some embodiments of the present disclosure, the system may be configured to collect data (including raw time and location-coded sensor activity data) via the sensor assembly, to store that data locally, to process the collected data to yield result data representing time and location-coded pressure information, and/or to communicate the collected raw sensor data or the processed result data to the second processing unit. The sensor assembly may comprise a plurality of discrete sensors, a sensor mesh, other conventionally known sensors suitable for the relevant requirements, or any combination thereof.
By placing specifically located pressure sensors or a pressure mesh or fabric underneath the leather cover of the baseball, the connection between the pitcher's fingers and the ball does not change. The pitcher can still feel comfortable with their grip as the tactile connection and coefficient of friction between the ball and the pitcher's fingers is maintained and consistent with real, in-game conditions. At the same time, the pressure sensing technologies embedded below the baseball's leather cover will map the pressure the pitcher's fingers exerted on the baseball. By collecting time stamped data at precise geolocated points on the baseball while keeping the tactile feeling and coefficient of friction of the baseball the same, reliable, and thus useful data can be obtained. This data is both valuable in isolation as lending insight into a player's specific habits and techniques and for its utility as additional data to be processed along with other, conventionally collected data (as discussed previously, such as spin rate, direction, and velocity) to create a more comprehensive understanding of a particular player or the sport at large including possible causal relationships between finger pressure and ultimate ball movement.
Other features, advantages and objects of the present disclosure will become apparent to those skilled in the art as a description of several presently preferred embodiments proceeds.
The following figures are included to illustrate certain aspects of the present disclosure and should not be viewed as exclusive embodiments. The subject matter disclosed is capable of modification, alteration, and equivalents in form and function, as will occur to one having ordinary skill in the art and the benefit of this disclosure.
The present disclosure relates generally to a system for measuring surface pressure. For purposes of this disclosure, the system shall be described with respect to embodiments in which the surface is that of a substantially spherical object though those skilled in the art would understand that the same design could be applied to other, non-spherical objects (such as, for example, a football). In some embodiments of the present disclosure, the system may comprise a housing body, a pressure sensor assembly, and a processing assembly.
As depicted in
The processing assembly 600 comprises a microcontroller 601. The processing assembly may further comprise a communication module 602, a data storage module 603, and a power supply module 604. A microcontroller may be a single microcontroller or a combination of microcontroller(s) and digital signal processor(s). A microcontroller may be configured to manage and execute data acquisition, computational, power management, and communication processes. The term “processor” refers to any and all such functional elements that may be carried out by a microcontroller. In some embodiments, the processing assembly 600 may be disposed within the housing body 100. For example, the processing assembly may be disposed in a hollowed, or partially hollowed, out core of a baseball. In other embodiments, the processing assembly may comprise an external system (such as a mobile phone, tablet, or personal computer) that is communicably coupled to the pressure sensor assembly. This communicable coupling may be direct or via an internal processor. In such further embodiments, the processing assembly 600 may include a first processing unit 610 disposed within the housing body and a second processing unit 620 external to the housing body 100 wherein the first and second processing units 610, 620 are communicably coupled.
The processing assembly 600 may be configured to receive or send data including raw sensor data measured by the pressure sensor assembly 500. The processing assembly 600 may be further configured to store the sensor data in memory 602. The processing assembly 600 may also be configured to perform computational analysis on the sensor data to produce result data representing time and location-coded pressure data. In embodiments having first and second processor units 610, 620, any configuration of the processing assembly may be applied fully or partially to one or both units. For example, the first processing unit 610 may be configured substantially identically to the fully internal processing assembly 600 in
The communication module 602 can be Bluetooth or other wireless communication module that receives and sends data to and from a personal device such as computer or mobile phone. The data storage module 603 can be a flash memory, and/or a volatile memory, or other memory storage device. The power supply module 604 may be a battery.
A pressure sensor assembly 500 may include any conventionally available sensor capable of being configured to sense and/or measure exerted pressure. The pressure sensor assembly 500 may be disposed within, on, or around the housing body 100. In some embodiments, the pressure sensor assembly 500 may be disposed between the exterior surface layer 101 and the interior core 102 of the housing body 100. In further embodiments, the pressure sensor assembly 500 may be disposed between the exterior surface 101 and the filler layer 103 of the housing body 100. In even further embodiments, the pressure sensor assembly 500 may be disposed on, around, or integrated with the exterior surface layer 101 of the housing body 100. The pressure sensor assembly may be further configured, as conventionally understood in the art, to measure time and geolocation data. A pressure sensor assembly 500 may include a pressure sensing fabric mesh 501 as shown in
In further embodiments, a pressure sensor assembly 500 may include at least one discrete pressure sensor 502 as shown in
Data generated by the sensor assembly 500 may then be, either internally or after communication to a system external to the housing body 100, stored or processed alongside other aggregated player data. Additionally, the data may be processed and displayed to a user according to conventional means such as in a visual “heat map” (similar to those depicted in
The following description is of an exemplary embodiment of a system (and performance of steps) in accordance with the present disclosure. In this embodiment, the sensor-embedded ball in accordance with this disclosure is a baseball. The ball is configured with a powered and unpowered state. When entering the powered state, the processing assembly, which includes an operably coupled power supply (battery) and memory, is configured to evaluate the amount of remaining power and memory. If both are above minimum threshold levels, the ball will be capable of data collection and enter a monitoring phase.
In the monitoring phase, the pressure sensor assembly will be sensing and measuring exerted pressure. The ball then determines whether it is being held in the pitcher's glove, is about to be thrown, or is in free flight. This determination is made by measuring the relative sensor activity across the ball's surface. For example, if the ball detects pressures in a relative arrangement and level consistent with a pitcher's fingers and that of a glove, it will determine that it is being held in the pitcher's glove. When the ball determines that it is about to be thrown (as signaled in some embodiments by the lack of glove pressure surrounding the ball over a preset time interval), the processing assembly will cause the ball to enter an enhanced data collection phase. Once in the enhanced data collection phase, the pressure sensor assembly will begin more rapidly capturing and storing pressure, time, and geolocation data. This increased data collection will occur until a release pressure threshold is detected. This release pressure threshold represents the point at which the pitcher has released the ball, and the ball is essentially in free flight whereby limited pressure is recognized around the entire ball. Data collection will then stop.
When data collection ceases, the ball may immediately begin communicating its collected or processed data to the external portion of the processing assembly. Alternatively, the ball may be configured to store such data in the internal portion of the processing assembly and delay communication until it is manually initiated either by the external portion or some actuation means (such as a button) on the surface of the ball. The external processing device may then store or process the data as desired.
If so configured, the ball may also begin internal processing of the data once data collection ceases. This may occur automatically, be initiated by a button press or other actuation means disposed on the ball, or be activated by a signal received from an external remote/system. The data may be stored in local memory and/or communicated as needed to an external system, and a microcontroller of the processing assembly will begin its analysis of that data if processing is initiated. The microcontroller will then generate result data representing time and location-coded pressure data. Depending on the design of the particular system, the microcontroller here may be either that disposed in a first internal processing unit or in a second external processing unit.
In embodiments having both a first internal and second external processing unit, when using the sensor electronics to limit the quantity of data that is transferred to an external processing unit, the internal processing unit may be configured to perform some or all of the processing and analysis and to communicate only a set of selected data. Selected data may include any results of the processing and analysis, sensor data, and/or portions thereof. At times when a communications channel is available, the selected raw sensor data can be transferred immediately. At times when no communications channel is available or when it is otherwise desirable to make such transfer at a later time, all data or the selected data may be stored in memory.
Although described broadly above, a more detailed, exemplary process diagram for an overall workflow for the pressure data capture and analysis system and method in accordance with various embodiments of the present disclosure is shown in
Step 00 is initiated immediately after the device is turned on or fully reset. There will be a self-diagnostic check to assure that the battery level is adequate, electronics package is functioning properly, and the memory capacity is ample for the ensuing tasks. Upon completion of the self-diagnostic check, a report will be sent to the remote computer (the second processing unit in this embodiment) stating all system parameters including an assessment whether the system is ready or not. At this point, the user can interact with the system via the remote computer to change settings, clear data, and other such activities.
Once Step 00 is complete, the system can move to Step 10. Following the completion of Step 00, Step 10 becomes active. As can be seen in the logic diagram in
Once the general geolocation of the athlete's fingers is determined, an algorithm (like the one used by the Dr. Scholls kiosk to select individual orthotics) is run to determine the pitch. By knowing the finger geolocated positions and pitch type, the internal electronics circuit (the first processing unit of this embodiment) can determine where the glove is located which provides the necessary backpressure to allow the athlete to get a good grip and feel for the ball. So long as back pressure is being sensed by the sensor assembly in the general location of where the glove is expected, the electronics circuit knows that the ball is still in the glove and the pitch sequence has not been initiated.
Step 20 begins when the electronics circuit determines that all backpressure from the glove is removed. This is determined when the pressure sensors in the area where the glove is established to be located return zero, or near zero, reading (such as, in some cases, a voltage reading). When the glove backpressure sensors provide data supporting that the athlete's fingers are the only pressure being exerted on the ball, the pitch sequence has been initiated. However, athletes have different tendencies, mannerisms, and routines whereby they may retouch the ball to the glove or place the ball back in the glove to get a better or different grip or change the pitch altogether. If the electronics circuit senses such a dynamic due to the backpressure sensor readings rising and signifying pressure, the system will then reset back to Step 10.
If though, the backpressure has not been reinitiated after a short period of time (maybe a quarter to a half of a second), the system establishes that the pitch sequence has been initiated and advances to Step 30.
Immediately upon entering Step 30, the data acquisition rate and sensor sensitivity are increased. In addition, such data acquisition may be limited to only those sensors or areas whereby pressure is being exerted to reduce the null data needing to be collected and processed. This time stamped and geolocated sensor data will be collected up until the final release point which is when the ball enters free flight and determined by all sensor readings going to zero or near zero. The pressure sensors may register some small amounts of pressure due to the air resistance on the leading surface of the ball; however, the pressure sensors will likely see pressure on and off due to the rotation of the ball and such sensors may not even have the response times to register the on/off nature of such air resistance driven pressure. Upon entering free flight, the data acquisition rate and sensitivity will be reset to those in Step 10 to reduce data collection, processing rates and required memory capacity or to stop data collection altogether.
There is always a situation whereby Step 30 is initiated and the athlete resets and places the ball back into the glove for any reason. In such a case and just like a similar situation in Step 20, the system will reset back to Step 10.
Following the initiation of entry into free flight in Step 30, the electronics circuit will begin looking for a fairly high pressure registered by sensors or a series of randomly located pressures which will symbolize that a catcher has caught to ball, the ball has come to rest in a net or against the backstop or has hit the ground. In all cases, these indications initiate Step 40 which is the end of the pitch.
In Step 40, the remote computer can send a signal to the electronics circuit that the data collection session is complete, thus advancing to Step 50. Alternatively, an algorithm will be developed to signify that the pitcher has the ball again in his glove resulting in the initiation of Step 10 for another pitch.
If the electronics circuit receives a command that the system is to be turned off and this Step 50 is initiated, all final data will be communicated, a self-diagnostic status check will be run, and a report generated and delivered to the operator. If no trouble shooting is necessary, the electronics circuit will turn itself off or enter a low power hibernation mode.
Although the present disclosure includes descriptions and illustrations relating to exemplary embodiments or objects thereof, it will be understood by those skilled in the art that various other changes, omissions, or additions may be made therein and thereto without departing from the scope of the present disclosure.
