Patent Publication Number: US-11638477-B2

Title: System and method for assessing toothbrush effectiveness

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATION 
     The present application is a continuation application of U.S. Non-Provisional patent application Ser. No. 16/188,385, filed Nov. 13, 2018, which claims the benefit of U.S. Provisional Patent Application Ser. No. 62/586,671, filed Nov. 15, 2017, the contents of which are hereby incorporated herein by reference in their entirety. 
    
    
     BACKGROUND 
     Clinical trials can be used to test the effectiveness of a toothbrush. But these trials are expensive and time consuming. Further, the brushing methods used by participants are inconsistent. What is needed is a system and method that efficiently and consistently tests the effectiveness of a toothbrush for a variety of brushing methods, including natural, unguided brushing methods. 
     BRIEF SUMMARY 
     The present disclosure may be directed, in one aspect, to a system for determining toothbrush effectiveness, the system comprising a data capture subsystem comprising at least one sensor and configured to generate brushing data during a participant brushing session directed entirely by the participant, and at least one processor configured to receive the brushing data from the data capture subsystem. A brushing simulation subsystem includes artificial teeth; and a robotic arm configured to: hold a toothbrush; and receive from the at least one processor instructions for a motion to be carried out by the robotic arm, the motion of the robotic arm causing the toothbrush to carry out an automated brushing session upon the artificial teeth, the motion of the robotic arm being based on the brushing data captured during the participant brushing session. 
     In another aspect, a method for determining toothbrush effectiveness includes a) providing a data capture subsystem comprising at least one sensor and configured to generate brushing data during a participant brushing session; b) instructing the participant to begin the participant brushing session, the participant brushing session being directed entirely by the participant; c) capturing the brushing data during the participant brushing session; d) transmitting the brushing data from the data capture subsystem to the at least one processor; e) instructing, by the at least one processor, a robotic arm to carry out a motion that causes a toothbrush to carry out an automated brushing session upon artificial teeth coated with a substance, the motion of the robotic arm being based on the brushing data captured during the participant brushing session; and f) determining an effectiveness of the toothbrush based on the substance determined to be removed from the artificial teeth during the automated brushing session. 
     In yet another aspect, a system includes a data capture subsystem comprising at least one sensor and configured to generate brushing data during a participant brushing session; at least one processor configured to receive the brushing data from the data capture subsystem; and a brushing simulation subsystem comprising artificial teeth coated with a substance; and a robotic arm configured to hold a toothbrush; and receive from the at least one processor instructions for a motion to be carried out by the robotic arm, the motion of the robotic arm causing the toothbrush to carry out an automated brushing session upon the artificial teeth, the motion of the robotic arm being based on the brushing data captured during the participant brushing session. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG.  1    is a block diagram of a system for testing toothbrush effectiveness according to one embodiment of the present invention. 
         FIG.  2    is an image of a participant using a brush tracking device according to one embodiment of the present invention. 
         FIG.  3    is a graph of brushing data captured from a participant manual brushing session according to one embodiment of the present invention. 
         FIG.  4    is an image of a robotic arm brushing artificial teeth according to one embodiment of the present invention. 
         FIG.  5    is an image of artificial teeth secured to a teeth holder according to one embodiment of the present invention. 
         FIG.  6    is an image of a force and torque sensor according to one embodiment of the present invention. 
         FIG.  7    is a flow chart for a method for determining toothbrush effectiveness according to one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention or inventions. The description of illustrative embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. In the description of the exemplary embodiments disclosed herein, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,” “down,” “left,” “right,” “top,” “bottom,” “front” and “rear” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description only and do not require that the apparatus be constructed or operated in a particular orientation unless explicitly indicated as such. Terms such as “attached,” “affixed,” “connected,” “coupled,” “interconnected,” “secured” and other similar terms refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. The discussion herein describes and illustrates some possible non-limiting combinations of features that may exist alone or in other combinations of features. Furthermore, as used herein, the term “or” is to be interpreted as a logical operator that results in true whenever one or more of its operands are true. Furthermore, as used herein, the phrase “based on” is to be interpreted as meaning “based at least in part on,” and therefore is not limited to an interpretation of “based entirely on.” 
     As used throughout, ranges are used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range. In addition, all references cited herein are hereby incorporated by referenced in their entireties. In the event of a conflict in a definition in the present disclosure and that of a cited reference, the present disclosure controls. 
     Features of the present invention may be implemented in software, hardware, firmware, or combinations thereof. The computer programs described herein are not limited to any particular embodiment, and may be implemented in an operating system, application program, foreground or background processes, driver, or any combination thereof. The computer programs may be executed on a single computer or server processor or multiple computer or server processors. 
     Processors described herein may be any central processing unit (CPU), microprocessor, micro-controller, computational, or programmable device or circuit configured for executing computer program instructions (e.g., code). Various processors may be embodied in computer and/or server hardware of any suitable type (e.g., desktop, laptop, notebook, tablets, cellular phones, etc.) and may include all the usual ancillary components necessary to form a functional data processing device including without limitation a bus, software and data storage such as volatile and non-volatile memory, input/output devices, graphical user interfaces (GUIs), removable data storage, and wired and/or wireless communication interface devices including Wi-Fi, Bluetooth, LAN, etc. 
     Computer-executable instructions or programs (e.g., software or code) and data described herein may be programmed into and tangibly embodied in a non-transitory computer-readable medium that is accessible to and retrievable by a respective processor as described herein which configures and directs the processor to perform the desired functions and processes by executing the instructions encoded in the medium. A device embodying a programmable processor configured to such non-transitory computer-executable instructions or programs may be referred to as a “programmable device”, or “device”, and multiple programmable devices in mutual communication may be referred to as a “programmable system.” It should be noted that non-transitory “computer-readable medium” as described herein may include, without limitation, any suitable volatile or non-volatile memory including random access memory (RAM) and various types thereof, read-only memory (ROM) and various types thereof, USB flash memory, and magnetic or optical data storage devices (e.g., internal/external hard disks, floppy discs, magnetic tape CD-ROM, DVD-ROM, optical disk, ZIP™ drive, Blu-ray disk, and others), which may be written to and/or read by a processor operably connected to the medium. 
     In certain embodiments, the present invention may be embodied in the form of computer-implemented processes and apparatuses such as processor-based data processing and communication systems or computer systems for practicing those processes. The present invention may also be embodied in the form of software or computer program code embodied in a non-transitory computer-readable storage medium, which when loaded into and executed by the data processing and communications systems or computer systems, the computer program code segments configure the processor to create specific logic circuits configured for implementing the processes. 
     Referring now to the figures,  FIG.  1    is a block diagram of a system  5  for testing toothbrush effectiveness according to one embodiment of the present invention. The system  5  includes a data capture subsystem  25  for capturing data regarding the brushing routines of one or more participants, and a simulation subsystem  25  for carrying out one or more brushing routines (or a combination thereof). In one embodiment, the data capture subsystem  25  can generate a digitized library of numerous human natural (unguided) brushing routines (or brushing routines guided by an outsider to some extent). The simulation subsystem  75  can use a robotic arm to simulate brushing routines based on one or more of the captured brushing routines, and then evaluate the cleaning performances for different toothbrushes using the brushing routines. 
     The system  5  includes a processor  10  that can form part of each of the subsystems  25 ,  75 , and can receive brushing data from the data capture subsystem  25 , as well as data from the robotic arm  80  and image scanning system  70  of the simulation subsystem  75 . In other embodiments, processor  10  can comprise a plurality of processors working together. For example, each subsystem  25 ,  75  can comprise one or more processors for carrying out the data processing discussed herein. It is noted that common components such as memory devices and power sources are not discussed herein, as their role would be easily understood by those of ordinary skill in the art. 
     The data capture subsystem  25  can include at least one data tracking device  24  for capturing brushing data. This brushing data can be indicative, for example, of a brush&#39;s motion and position during a brushing routine. In the exemplified embodiment, the brushing data is captured during a natural, unguided brushing session that is directed entirely by the participant. In other embodiments, the brushing session can be guided only insofar as the participant is told which general area to brush, and/or for how long. For example, the participant can be instructed to brush each quadrant of the mouth for 30 seconds, but not told the type of brushing motion to use. Or the participant can be asked to brush six areas of the mouth successively for 30 seconds each, these areas being the upper left molars, the upper front teeth (canine to canine), the upper right molars, the lower left molars, the lower front teeth, the lower right molars. In yet another embodiment, the brushing session can be guided by more specific instructions being provided to the participant (such as the brushing motion and/or frequency to use). Such instructions can be provided, for example, by using a tablet, smartphone, or intercom. The system  25  can be configured to digitally store brushing data for numerous different brushing routines, each linked to a specific participant. 
     In the exemplified embodiment, the data capture subsystem  25  includes the following data tracking devices  24 : a brush tracking device  40 , a head motion tracking device  50 , a wrist motion tracking device  60 , and a camera  20 . The system  25  can also include a data logger  30  configured to receive brushing data from one or more brush tracking devices  24 , store the brushing data, and transmit the brushing data to the processor  10 . The data logger  30  can comprise multiple data loggers. In other embodiments, one or more of the data tracking devices  24  can send data directly to the processor  10 . 
     The different devices will be discussed below in turn. The data capture subsystem  24  need not include each of these devices, but rather can include other devices, just one device, or any combination of devices, for capturing brushing data. Brushing data can concern parameters such as position, motion, acceleration, frequency, angle, and force (against the surface of the teeth). 
     In general, each tracking device  24  that is used for the data capture subsystem  25  generates at least part of the brushing data. For purposes of the present disclosure, the term “brushing data” is any type of information related to brushing during a brushing session that may be extracted or derived from a sensor or sensor signal, or from an image-capturing device such as a camera, regardless of the form of the extracted information, and combinations thereof. By way of example, brushing data may be in the form of mathematical data (such as a formula which mathematically represents at least part of the sensor signal), analog data (such as the waveform of the sensor signal), and/or digital data (such as a representation of at least part of the sensor signal in a digital format). 
     In the exemplified embodiment of  FIG.  1   , the data capture subsystem  25  includes a brush tracking device  40  configured to hold a first toothbrush of a participant. The brush tracking device  40  includes sensors  41 ,  42 ,  43 ,  44 , at least one of which being configured to generate motion data during the participant brushing session, the motion data forming part of the brushing data. Specifically, in this embodiment, the first sensor  41  is a 3-axis accelerometer, the second sensor  42  is a 3-axis gyroscope, and the third sensor  43  is a 3-axis magnetometer. In one embodiment, a single chip including these different sensors can be used to provide 9 degrees of freedom. For example, the LSM9DS1 inertial measurement unit (IMU) chip from STMicroelectronics has this capability. In other embodiments, other types or combinations of sensors can be used, including a single sensor, such as a 6-axis accelerometer. For purposes of the present disclosure, the term “motion data” is any type of information related to a motion of a toothbrush (including acceleration, velocity, position, angle, and force) which may be extracted or derived from a sensor or sensor signal, regardless of the form of the extracted information, and combinations thereof. 
     Sensor data provided to the processor  10  can be used to determine other values. For example, pitch, roll, and/or heading data can be calculated from the accelerometer and gyroscope readings. Further, a majority of toothbrush motions resemble continuous oscillatory behavior, and the frequency of these motions can be calculated from the above sensor readings. 
     Further, the brush tracking device (or the data capture subsystem in general) can include a force sensor  44  configured to generate force data during the participant brushing session indicative of a force that bristles of the first toothbrush apply to the participant&#39;s teeth, the force data forming part of the brushing data. A system incorporating the above sensors can determine brush forces, frequency, and stroke size (and pattern) at certain locations. 
       FIG.  2    is an image of a participant using a brush tracking device  40  according to one embodiment of the present invention. In the exemplified embodiment, the brush tracking device  40  has a housing that fits around at least a portion of the first toothbrush  44  of the participant  1 . The sensors  41 ,  42 ,  43 ,  44  can be located within or on that device housing. Further the data from the brush tracking device  40  can be communicated to the processor by a wired or wireless connection. 
       FIG.  3    is a graph  6  of brushing data captured from a participant brushing session according to one embodiment of the present invention. The graph  6  shows X, Y, and Z accelerations, force, and frequency for six seconds of brushing on the occlusal side of the molars. Positive values of acceleration follow the direction of the arrows displayed on the toothbrush graphic  8  also provided. 
     Motion path can be mapped in a program such as MATLAB for each participant. These motion paths can be used as guides for the robotic arm. MATLAB motions paths can then be translated to instructions for the robotic arm, such as WAM C++ instructions, to thereby enable the robotic arm to follow along the calculated motion paths. 
     Returning to  FIG.  1   , the data capture subsystem can further include a camera configured to capture image data during the participant brushing session, the image data forming part of the brushing data. Image data can be provided to a processor (such as processor  10 ), which can use image processing tools to determine or confirm the position or motion of the brush, including the brush head. For purposes of the present disclosure, the term “image data” is any type of information indicative of an image, including information extracted or derived from other information or data indicative of an image, regardless of the form of the extracted information, and combinations thereof. The image data may be in the form of mathematical data, analog data, and/or digital data. 
     As shown in  FIG.  1   , the data capture subsystem can further include a head motion tracking device  50  configured to attach to a portion of the head of the participant, the head motion tracking device  50  including a head motion sensor  51  capturing head motion data during a participant brushing session, the head motion data forming part of the brushing data.  FIG.  2    shows the head motion tracking device  50  attached to the head  2  of a participant  1 . 
     Head movement may add to or subtract from the actual motion delivered to the teeth. The head motion tracking device  50  detects additional brush motion created by head movement. The head motion tracking device can be a 9-degrees-of-freedom motion sensor equipped with an accelerometer, gyroscope, and magnetometer to analyze the head angle and movement of an individual using the brush tracking device. Head motions along the horizontal and vertical axes can be used to modify the brush motions and accommodate for extraneous head movement. 
     Returning to  FIGS.  1  and  2   , the data capture subsystem can further include a wrist motion tracking device  60  configured to attach to the participant&#39;s wrist and including at least one sensor  61  for capturing wrist-motion data, the wrist-motion data forming part of the brushing data. In one embodiment, the wrist motion tracking device  60  includes an accelerometer, gyroscope, and Bluetooth interface. The wrist motion tracking device  60  can be attached to the wrist and/or arm, and can be remotely controlled by a smartphone. The wrist motion tracking device  60  can capture movement, position, and rotation of the wrist, arm, and/or brush. In an alternative embodiment, rather than the brush tracking device and wrist motion tracking device each having sensors such as an accelerometer and gyroscope, those sensors can be present only in the wrist motion tracking device, while the brush tracking device houses a force and torque sensor. 
     Simulation Subsystem 
     Returning to  FIG.  1   , as discussed above, the system  5  further includes a simulation subsystem  75 . This subsystem  75  can include artificial teeth  90  coated with a substance and a robotic arm  80  configured to hold a second toothbrush. The robotic arm  80  can also be configured to receive from the at least one processor  10  instructions for a motion to be carried out by the robotic arm  80 , the motion of the robotic arm  80  causing the second toothbrush to carry out an automated brushing session upon the artificial teeth  90 . The motion of the robotic arm can be based on the brushing data captured from the data capture subsystem  25  during the participant brushing session. The at least one processor  10  can be configured to determine an effectiveness of the second toothbrush based on the substance determined to be removed from the artificial teeth  90  during the automated brushing session. 
     The simulation subsystem  75  can be configured to carry out multiple automated brushing sessions on multiple artificial teeth to test the effectiveness of the second toothbrush. In this case, the brushing simulation subsystem  75  is configured to repeat the carrying out of the automated brushing session for a plurality of artificial teeth  90  having the substance. Further, the determination of the effectiveness of the second toothbrush is based on the substance determined to be removed from each of the plurality of artificial teeth during each automated brushing session. 
     Further, the data capture subsystem  25  can be configured to carry out multiple data capture sessions. In this case, data capture subsystem  25  is configured to repeat the capture of the brushing data for a plurality of participant brushing sessions from a plurality of participants. Further, the motion of the robotic arm can be based on the brushing data from the plurality of participant brushing sessions. For example, the processor  10  can process the brushing data from the participants and create a composite brushing session that is based on one or more participant brushing sessions. For example, brushing sessions can be divided into different categories, and each category of brushing sessions can have a composite brushing session that is representative of one or more of the brushing sessions in the category. Alternatively, an overall composite brushing session can be created based on a plurality of brushing sessions. This overall composite brushing session can attempt to represent a typical human brushing session. Different mathematical methods can be used to process the brushing data to combine brushing data from different brushing sessions. In yet another embodiment, the robotic arm can carry out separate automated brushing sessions for each participant brushing session, where each automated brushing session simulates a single participant brushing session. The invention is not limited to any single approach. 
       FIG.  4    is an image of the robotic arm  80  brushing artificial teeth  90  according to one embodiment of the present invention. Several types of robotic arms can be used, such as the WAM™ robot arm from Barret Technology Inc, which has seven degrees of freedom and can mimic human arm range of motion. Such a robotic arm can be programmed to carry out an automated brushing session based on brushing data from participant brushing sessions. 
     This figure also shows the second toothbrush  84  held by the robotic arm  80 , the second toothbrush  84  brushing the artificial teeth  90 . The artificial teeth are held by a teeth holder  92  for holding the teeth in a fixed position during an automated brushing session. Further, the robotic arm can include a force and torque sensor  82 . This sensor  82  is discussed in more detail below. 
       FIG.  5    is an image of artificial teeth  90  secured to a teeth holder  92  according to one embodiment of the present invention. The brushing simulation subsystem includes the rigid teeth holder  92  for holding the artificial teeth in a fixed position. In the exemplified embodiment, the teeth holder  92  is a rigid aluminum structure to which the artificial teeth are bolted, and the height of the aluminum tubing is optimal for interaction with the robot-guided second toothbrush. In other embodiments, other structures can be used to secure the artificial teeth during an automated brushing session. 
     The artificial teeth  90  can include a substance  91 . In one-embodiment, the substance is a plaque-like coating, though the invention is not so limited. An image scanning system  70  (see  FIG.  1   ) can be configured to capture images of the artificial teeth before and after the automated brushing session. The images can be processed to determine a cleanliness score for each image based on how much of the substance is present. The change in score can be used to determine how effective the second toothbrush was at removing plaque when using the automated brushing session. In other embodiments, other approaches can be used for determining how effectively the artificial teeth are cleaned. 
     As discussed above, the robotic arm  80  can include or utilize a force sensor and/or torque sensor  82  configured to provide feedback as to whether an applied motion and force to the artificial teeth corresponds with the brushing data captured during the participant brushing session. In the exemplified embodiment, the sensor  82  is a 6-axis force and torque sensor and is installed at the robot endpoint to increase the resolution of the low-level endpoint forces (see  FIG.  6   ). 
     To impart a constant force relative to the bristles&#39; direction, the system can have an open loop mode that utilizes a force-torque sensor. In the open loop control mode, the robotic arm can apply motor torques that will theoretically produce the desired applied force at the toothbrush bristles. The closed loop mode can use readings from the force-torque sensor at the robot&#39;s endpoint and modify the applied motor torques to more closely achieve the desired force. This mode provides more accurate force control than an open loop mode and ensures that the bristles remain in contact with the teeth. In other embodiments, an open loop mode (with a force or torque sensor) can be used. 
     According to one embodiment shown in  FIG.  7   , a method for determining toothbrush effectiveness can include providing a participant a data capture subsystem configured to capture brushing data during a participant brushing session, the data capture subsystem comprising a brush tracking device configured to hold a first toothbrush and comprising at least one motion sensor, the at least one motion sensor configured to generate motion data during the participant brushing session, wherein the motion data forms part of the brushing data. 
     The participant can be instructed to begin the participant brushing session, the participant brushing session being directed entirely by the participant (operation  201 ). Further, the brushing data can be captured during the participant brushing session (operation  202 ). Further, the brushing data can be transmitted from the data capture subsystem to the at least one processor. Further, the at least one processor can instruct a robotic arm to carry out a motion that causes the second toothbrush to carry out an automated brushing session upon artificial teeth coated with a substance, the motion of the robotic arm being based on the brushing data captured during the participant brushing session (operation  203 ). Further, the effectiveness of the second toothbrush can be determined based on the substance determined to be removed from the artificial teeth during the automated brushing session (operation  204 ). The inventions, however, are not so limited. 
     The embodiments discussed herein provide several advantages. For example, they enable the testing and evaluation of different toothbrush designs under similar or identical conditions, thus dramatically reducing the time-to-market and development costs by enabling faster brush testing. This approach will also eliminate much of the variability and subjectivity from testing and product-development, while still considering the natural, unguided brushing motions of typical toothbrush users. 
     While the invention has been described with respect to specific examples including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described systems and techniques. It is to be understood that other embodiments may be utilized and structural and functional modifications may be made without departing from the scope of the present invention. Thus, the spirit and scope of the invention should be construed broadly as set forth in the appended claims.