Abstract:
The present invention discloses a system and accompanying method for directing the movement of an object on an interactive surface through a defined path. The system includes an object embedded with a unique identification code (UID), a movement module, and a distinct pattern of capacitive tabs near the surface of the object that makes contact with the interactive surface, an interactive surface configured to recognize the UID, location and orientation information of an object placed on the interactive surface, and a processor operatively linked to the interactive surface and configured to direct, track and correct the movement of the object along a defined path on the interactive surface by tracking the UID, location and orientation of the object continuously and throughout the movement. A centralized control mode is applied in the present invention, which makes the structure of the electronic hardware within the moving object substantially simplified, which leads to a decreased manufacturing cost, and, from an aesthetic point of view, the logic clearer and easily understood.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation in part of International Patent Application PCT/CN2015/072626, entitled “A System and Method for Directing an Object to Move on an Interactive Surface through a Defined Path”, filed on Feb. 10, 2015, which is a continuation in part of International Patent Application PCT/CN2014/086745, entitled “System and Method for Directing a Small Scale Object to Generate a Sensory Output to a User Powered by RF Energy Harvesting”, filed on Sep. 17, 2014, which is a continuation in part of International Patent Application PCT/CN2014/085668, entitled “System and Method for Directing a Targeted Object on an Interactive Surface to Produce a Response”, filed on Sep. 1, 2014, which is a continuation in part of International Patent Application PCT/CN2014/084498, entitled “System and Method for Directing a Moving Object on an Interactive Surface”, filed on Aug. 15, 2014. 
         [0002]    International Patent Application PCT/CN2015/072626 is also a continuation in part of International Patent Application PCT/CN2014/090890, entitled “System and Method for Recognizing Objects with Continuous Capacitance Sensing”, filed on Nov. 12, 2014, which is a continuation in part of International Patent Application PCT/CN2014/080495, entitled “System and Method to Recognize an Object&#39;s ID, Orientation and Location Relative to an Interactive Surface”, filed on Jun. 23, 2014, which is a continuation in part of International Patent Application PCT/CN2014/079892, entitled “System and Method for Identifying an Object&#39;s ID and Location Relative to an Interactive Surface”, filed on Jun. 13, 2014, which is a continuation in part of International Patent Application PCT/CN2014/072961, entitled “System and Method for Identifying an Object&#39;s ID and Location Relative to an Interactive Board”, filed on Mar. 6, 2014. 
         [0003]    International Patent Application PCT/CN2015/072626 is also a continuation in part of International Patent Application PCT/CN2014/093763, entitled “Apparatus and Method for Eliminating Blind Spot in an RF Antenna Array”, filed on Dec. 12, 2014. 
         [0004]    The entire disclosures of each of the above applications are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0005]    The present invention relates to a system and accompanying method wherein an object is moved over an interactive surface along a defined path. 
       BACKGROUND 
       [0006]    Systems that allow for game pieces to physically move upon the surface of a game board without the assistance of a player so as to play against an A.I. opponent (or another player who doesn&#39;t physically move a game piece) are known. U.S. Pat. No. 4,398,720 A entitled “Robot computer chess game” and U.S. Pat. No. 7,780,513 B2 entitled “Board game system utilizing a robot arm” depict systems and accompanying methods for a player to play an A.I. opponent with chess game pieces being physically moved by the A.I. These prior arts make use of a robot arm electrically connected to the computing device and wherein when the board game program is executed, the computing device controls the robot arm to touch the game surface with the contact end to interactively play the board game with a user. There exist a number of drawbacks in using a robot arm to physically pickup game pieces: 
         [0007]    firstly, from a purely aesthetic point of view, having a robot arm affixed on the periphery of the board is an awkward design; 
         [0008]    secondly, restrictions on the robot arm only being able to manipulate only one game piece at a time as well as the mechanical components of the robot arm itself means that the opponent&#39;s moves will be slow and awkward relative to that of the player. 
         [0009]    It is a major disadvantage of the prior art that an A.I. opponent cannot move multiple game pieces simultaneously. 
         [0010]    U.S. Pat. No. 8,737,035 B2 entitled “Magnetically movable objects over a display of an electronic device” describes a method for an object to move relative to a restricted surface area. The method includes imparting motion to the magnetically movable object by adjusting a magnetic field applied to the magnetically movable object through the display of the electronic device. Unfortunately a major drawback to such a method is that only a single object can be physically moved along the surface. Furthermore, the orientation of the object cannot be determined. Thus, the applications for such a method are seriously limited. 
         [0011]    CN102039045 A discloses an interactive surface embedded with an array of RF antennas capable of locating multiple objects embedded with RFID tags placed upon the surface. US 20110272884 A1 entitled “Transport of an object across a surface” describes a system whereby an object uses transport mechanisms to move along a surface. The combination of both prior art cited above would generate a system whereby multiple objects can move upon an interactive surface according to instructions from a computer system. However, such a system cannot accurately identify the orientation of each object relative to the interactive surface, nor can such a system direct the movement of the object along a defined path which can be sometimes a straight line and other times a bending movement along an arc. Thus, game piece movements that perform smooth turns and follows complex defined path cannot be performed using the prior art. 
         [0012]    U.S. Pat. No. 7,245,760 B2 entitled “Robot for making an interface surface” describes a robot that can accurately change its position and orientation along a restricted surface area. U.S. Pat. No. 7,245,760 B2 utilizes a distributed control model and requires each moving object to have the ability to determine its location and movement parameters. The surface has imprinted coded data that identify a plurality of locations that the robot itself can recognize through the use of an image sensor. Although U.S. Pat. No. 7,245,760 B2 resolves some of the deficiencies identified in the above-mentioned prior arts, the electronics embedded within each robot are costly and the use of plurality of these robots in order to develop an interactive board game could prove to be uneconomical. 
       SUMMARY OF THE INVENTION 
       [0013]    In order to resolve the drawbacks of the aforementioned prior arts, the present invention describes a system and accompanying method whereby an interactive surface is configured to track and direct an object to physically change its position and orientation accurately and along a defined path relative to the interactive surface. 
         [0014]    In accordance with one embodiment of the present invention, the system includes: 
         [0015]    an object embedded with a unique identification code (UID), a movement module, and a distinct pattern of capacitive tabs near the surface of the object that makes contact with the interactive surface; 
         [0016]    an interactive surface configured to recognize the UID, location and orientation information of an object placed on the interactive surface at any location and in any orientation; 
         [0017]    a processor operatively linked to the interactive surface. 
         [0018]    The processor is configured to direct, track and correct the movement of the object along a defined path on the interactive surface by tracking the UID, location and orientation of the object continuously and throughout the movement. 
         [0019]    The interactive surface further includes, embedded beneath the surface, a first array of high-frequency RF antennas for detecting the UID of an object and a dense array of capacitance sensors for detecting the location and orientation of an object. 
         [0020]    The system further includes a second high-frequency RF antenna array that is not connected to a reader or any electrical path, and each antenna of the second RF antenna array covers a blind spot of the first array of RF antennas. 
         [0021]    Each object further includes a microcomputer unit (MCU) that controls the movement module. 
         [0022]    The processor directs the movement of the object by wireless communication modules that are embedded in the object and the interactive surface. 
         [0023]    The wireless communication module can be a 2.4 GHz module, a Bluetooth module, or a WIFI module. 
         [0024]    The movement module includes a motor for forward and backward movement, a motor for making turns, and a power source. 
         [0025]    The processor formulates a movement instruction, a course correction instruction, and a movement completion notice based on the UID, location and orientation of the object, continuously and throughout the movement of the object. 
         [0026]    The system further includes a set of movement rules to define the path of movement of the object, and the set of movement rules is executed by either a local server or a remote server. 
         [0027]    The system further includes multiple objects, and the paths of movement of the objects are defined by the set of movement rules. 
         [0028]    The method for directing the movement of an object on an interactive surface through a defined path is as follows: 
         [0029]    step 1: in the initialization stage, the processor of the interactive surface sends an instruction to the MCU of the object, for the MCU to record the host number and host address of the interactive surface and the device number and device address of the object, creating a master-slave relationship for the moving object to be controlled by the interactive surface; 
         [0030]    step 2: once the moving object is placed on the interactive surface, the capacitance sensor array and controller detects the capacitance tabs and sends the capacitive coupling information to the processor; the RF antenna array and reader detects the UID of the RFID tag and sends the UID information to the processor; 
         [0031]    step 3: the processor calculates the location and orientation of the moving object based on the capacitive coupling information and the UID information received; 
         [0032]    step 4: the destination and the associated movement path are determined by game rules; the processor sends an instruction wirelessly to the MCU through the respective communication modules of the object and the interactive surface; the instruction sent by the processor includes the host number and host address of the interactive surface, the device number and device address of the object, and commands for the motors and controllers within the movement module to execute; the MCU receives the instruction, confirms that the instruction is for the object, and sends the instruction to the movement module; the movement module then starts the movement according to the instruction; 
         [0033]    step 5: the movement of the object results in a change of capacitive coupling between the capacitance tab and the capacitance sensor array, and the capacitance sensor array and controller sends the capacitive coupling information to the processor; the RF antenna array and reader  504  once again detects the UID of the RFID tag to confirm the identity of the object with changed location and orientation and then sends the UID information to the processor; 
         [0034]    step 6: the processor receives the information, calculates the new location and orientation of the object and determines whether the object has reached the intended destination; if the object has not reached the intended destination, the processor determines whether the object has stayed on the correct path with the correct orientation; if the object has not stayed on the correct path or had the correct orientation, the processor issues a new instruction as outlined in step 4, and the steps 4, 5 and 6 are repeated until the processor determines that the moving object has reached the intended destination through the associated movement path and with the correct orientation. 
         [0035]    step 7: the process is over as the object reaches the intended destination. 
         [0036]    A centralized control mode is applied in the embodiment of the present invention. With this mode, the interactive surface obtains the UID, location and orientation information of the moving object placed on the surface so as to direct the movement of the object. As a result, the structure of the electronic hardware within the moving object is substantially simplified, which leads to a decreased manufacturing cost, and, from an aesthetic point of view, the logic is clearer and easily understood. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0037]    To better illustrate the technical features of the embodiments of the present invention, various embodiments of the present invention will be briefly described in conjunction with the accompanying drawings. It should be obvious that the drawings are for exemplary embodiments of the present invention, and that a person of ordinary skill in the art may derive additional drawings without deviating from the principles of the present invention. 
           [0038]      FIG. 1  is an exemplary schematic diagram illustrating a bird&#39;s eye view of an interactive surface and a plurality of objects used in an interactive naval warfare board game in accordance with one embodiment of the present invention. 
           [0039]      FIG. 2  is an exemplary schematic diagram of a cross-sectional view of the system for the interactive board game depicted in  FIG. 1  segmented into layers for illustration purposes in accordance with one embodiment of the present invention. 
           [0040]      FIG. 3  is an exemplary schematic diagram that further illustrates a cross sectional view of the interactive surface and a vessel for the board game illustrated in  FIG. 1  and  FIG. 2  in accordance to one embodiment of the present invention. 
           [0041]      FIG. 4  is an exemplary schematic diagram that illustrates a bird&#39;s eye view of the interactive surface&#39;s conductive sensors and a vessel for the board game illustrated in  FIGS. 1, 2 and 3  in accordance to one embodiment of the invention. 
           [0042]      FIG. 5  is an exemplary schematic diagram that illustrates a process flow in accordance to one embodiment of the invention. 
           [0043]      FIG. 6  is an exemplary schematic diagram that illustrates an interactive surface designed to play a variant of the game “Candy Land” in accordance to one embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0044]    Reference will now be made in detail to various embodiments of the invention. While the invention will be described in conjunction with the embodiments, it will be understood that this is not intended to limit the scope of the invention to these specific embodiments. The invention is intended to cover all alternatives, modifications and equivalents within the spirit and scope of invention, which is defined by the apprehended claims. 
         [0045]    Furthermore, in the detailed description of the present invention, specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be obvious to one of ordinary skill in the art that the present invention may be practiced without these specific details. For example, “capacitance sensor” and “capacitive tab” technology are discussed in this present invention as examples technology and for the purpose of simplicity; however, other sensor technologies can also be adapted for the purpose of this present invention and are within the scope of the present invention. In other instances, well known methods, procedures, components, and circuits are not described in details to avoid unnecessarily obscuring a clear understanding of the present invention. 
         [0046]    The present invention may be better understood and its numerous objectives and advantages will become apparent to those skilled in the art by reference to the accompanying drawings. 
         [0047]    The present invention describes a system whereby an interactive surface for tracking and directing an object to physically change to move along a defined path, including: 
         [0048]    an object embedded with a unique identification code (UID), a movement module, and a distinct pattern of capacitive tabs near the surface of the object that makes contact with the interactive surface; 
         [0049]    an interactive surface configured to recognize the UID, location and orientation information of an object placed on the interactive surface at any location and in any orientation; 
         [0050]    a processor operatively linked to the interactive surface; 
         [0051]    the processor is configured to direct, track and correct the movement of the object along a defined path on the interactive surface by tracking the UID, location and orientation of the object continuously and throughout the movement. 
         [0052]    In the embodiment described in  FIG. 1 , the interactive surface is designed to represent the sea and the objects  102  are designed to resemble miniature naval vessels during the Age of Sail (1650-1815) such as frigates or Man-of-War. Elements  103  such as islands, rocks and coral reefs are also placed on the interactive surface so as to create strategic obstacles during gameplay. 
         [0053]    The objective of the game described in  FIG. 1  could be to destroy the enemy fleet or scenario based (e.g., safeguard the passage of a trade convoy). The enemy fleet the player faces is remotely controlled by a processor which could be dependent on A.I. or another player that is not physically moving his vessels. 
         [0054]    In order to play the naval battle board game described in  FIG. 1 , a player must, on their turn, physically move one or more of his vessels along the board. This action can be performed manually or through the use of a remote control device. Another alternative design for the movement of the player&#39;s vessels would be through the use of voice command recognition technology. 
         [0055]    A player&#39;s vessels actions will be restrained by various elements of the games. For example, the distance a particular vessel can move will depend on the predetermined speed (which is depicted as distance in turn-based games) and the speed and direction of the wind. The damage and rate of fire of a vessel will also be dependent of criteria such as vessel type, damaged taken, orientation of the vessel vis-a-vis target, etc. The speed by which a vessel turns (i.e., the angle of the turn arc) is also an important criterion. All of these criteria are game design specific and dependent on the electronic program run on the system&#39;s processor. 
         [0056]    The interactive surface (i.e., the game board)  101  has, embedded beneath the surface, a first array of high-frequency RF antennas for detecting the unique ID of moving objects placed on the surface, for example, a player&#39;s vessel  102 , and a dense array of capacitance sensors for detecting the location and orientation of the object. Once, a player has completed their turn, the processor is configured, based on either an A.I. instruction or other players command, to direct an enemy vessel  104  to move in response to the action of the player&#39;s vessel  102 . 
         [0057]    As seen in  FIG. 2 , the interactive surface  101  comprises of four layers. The bottom layer  202  is the base of the board and is used as support. The second layer  203  is embedded with an RF antenna array and reader whose function is to wirelessly communicate with the electronic modules embedded within each individual vessel  102  or  104  in order to identify the UID and direct the vessels to move. The third layer  204  comprises of a densely packed capacitance sensor array and controller whose purpose is to accurately identify the position and orientation of each vessel  102  or  104  through capacitive coupling with the vessels&#39; distinct pattern of capacitance tabs. Finally the top layer  205  is used as a both a protective sheet and the design of the naval arena. 
         [0058]    The system further includes a second high-frequency RF antenna array that is not connected to a reader or any electrical path. An antenna in the second array is used to cover the blind spot of the first array in detecting an RFID tag on the object, for example, the vessel, by augmenting the electromagnetic field of the blind spot areas of the first array. 
         [0059]    Each object placed on the interactive surface, for example, the vessel  102 , can further include a microcomputer unit (MCU) that controls the movement module. 
         [0060]    The processor directs the movement of the object by wireless communication modules that are embedded in the object and the interactive surface. The wireless communication module can be a 2.4 GHz module, a Bluetooth module, or a WIFI module. 
         [0061]      FIG. 3  illustrates how a vessel&#39;s  102  UID and position is determined by the interactive surface (game board)  301  and how the processor directs the vessel  102  to move relative to the interactive surface  301 . 
         [0062]    As illustrated in  FIG. 3 , once a vessel  102  is placed upon the interactive surface  101 , the distinct pattern of capacitance tabs  303  placed at the bottom of the vessel  102  couple with the capacitance sensors directed in the third layer  204  of the interactive board  101 . Using the information as to which capacitance sensors have experienced a change in capacitance, the processor can, through inductive reasoning, determine the location of the vessel  102  placed upon the interactive surface  101 . The processor then directs the RF antenna(s) of the second layer  203  located in closest proximity to the capacitance sensors that are experiencing a change in capacitance to wirelessly communicate with the vessel&#39;s  102  electronic module and obtain that vessel&#39;s  102  UID. Thus, the vessel&#39;s UID and position relative to the interactive surface is determined. 
         [0063]      FIG. 4  further illustrates how a vessel&#39;s  102  orientation relative to the interactive surface  101  is determined. Embedded at the base of the vessel  102  are a distinct pattern of capacitance tabs  303 . Once a vessel  102  is placed upon the interactive surface  101 , these capacitance tabs couple with the capacitive sensors of the capacitive sensor array  404 . From the pattern of capacitive sensors that have experienced a change in capacitance, the processor determines both the position and the orientation of the vessel relative to the interactive surface  101 . 
         [0064]    The abovementioned process by which a vessel&#39;s position, UID and orientation is determined by the processor is the same for a player&#39;s vessels and the A.I. opponent&#39;s vessels. 
         [0065]    The abovementioned movement module includes a motor for forward and backward movement, a motor for making turns, and a power source. Once a player completes his actions on his turn, the processor directs the opponent&#39;s vessel  104  to move according to an electronic program. As previously stated these movements can be the result of A.I. programming or that of another player&#39;s commands. Referring back to the  FIG. 3 , one can see that each vessel  102  is embedded with a motor  306 , steering device  307  and wheels  308  to allow for the accurate movement of the object relative to a surface in response to movement instructions received from the processor by the vessel&#39;s  302  electronic module  309 . 
         [0066]    The game board surface  101  can further include multiple vessels, and the paths of movement of the vessels are defined by the set of movement rules. 
         [0067]    Given the dynamics of “Age of Sail” naval warfare, orientation of vessels relative to each other is a crucial strategic element since a vessel whose broadside is facing an incoming vessel is generally seen as at an advantage. The orientation of the vessel relative to the wind is also a crucial element of naval warfare tactics during the Age of Sail. Thus, the game embodiment described herein makes full use of the orientation and smooth steering of the vessels along arcs or curved paths. Referring back to  FIG. 1 , the bold arrows numbered 1 to 3 depict the curved path of each vessel  102 ,  104  upon a turn. In this scenario, the electronic program is configured to cause the vessels&#39;  102 ,  104  speed (i.e., distance per turn) and curvature of turns (i.e., vessel turn arc) to be affected by wind blowing from west to east as well as the vessels&#39;  102 ,  104  inherent steering attributes. As the opponent&#39;s vessel  104  is facing a headwind, the length and angle of its turn arc is shorter than if it had its back to the wind, thus, limiting its maneuverability in game. 
         [0068]      FIG. 5  is an exemplary schematic diagram that illustrates the process flow of the system, in the following steps: 
         [0069]    Step 1: In the initialization stage, the processor  503  of the interactive surface  101  sends an instruction to the MCU  507  of the vessel  102 , for the MCU  507  to record the host number and host address of the interactive surface  101  and the device number and device address of the vessel  102 , creating a master-slave relationship for the vessel  102  to be controlled by the interactive surface  101 . 
         [0070]    Step 2: Once the vessel  102  is placed on the interactive surface  101 , the capacitance sensor array and controller  505  detects the capacitance tabs  303  and sends the capacitive coupling information to the processor  503 ; the RF antenna array and reader  504  detects the UID of the RFID tag  508  and sends the UID information to the processor  503 . 
         [0071]    Step 3: The processor  503  calculates the location and orientation of the vessel  102  based on capacitive coupling information and the UID information received in step 2. 
         [0072]    Step 4: The destination and the associated movement path are determined by game rules; the processor  503  sends an instruction to the MCU  507  through the 2.4 GHz communication module  506  to the 2.4 GHz communication module  510  wirelessly. The instruction sent by processor  503  includes the host number and host address of the interactive surface  101  and the device number and device address of the vessel  102 , and commands for the motors and controllers within the movement module  511  to execute. The MCU  507  receives the instruction, confirms that the instruction is for the vessel  102 , and sends the instruction to the movement module  511 . The movement module  511  then starts the movement according to the instruction. 
         [0073]    Step 5: The movement of the vessel  102  results in a change of capacitive coupling between the capacitance tab and the capacitance sensor array and controller; the capacitance sensor array and controller  505  sends the capacitive coupling information to the processor  503 ; the RF antenna array and reader  504  once again detects the UID of the RFID tag  508  to confirm the identity of the vessel  102  and sends the UID information to the processor  503 . 
         [0074]    Step 6: The processor receives the UID, location and orientation information in step 5, calculates the location and orientation of the vessel  102  and determines whether the vessel  102  has reached the intended destination. If the vessel  102  has not reached the intended destination, the processor  503  determines whether the vessel  102  has stayed on the correct path with the correct orientation. If the vessel  102  has not stayed on the correct path or had the correct orientation, the processor  503  issues a new instruction as outlined in step 4, and the steps 4, 5 and 6 are repeated, until the processor  503  determines that the vessel  102  has reached the intended destination through the associated movement path and with the correct orientation. In brief, the commends for movement, the commends for process correction and the notices of movement completion have been created continuously and throughout the movement. 
         [0075]    Step 7: The game is over as the object reaches the intended destination, and the notice of completion is sent. 
         [0076]      FIG. 6  is an exemplary schematic diagram that illustrates the play of the game “Candy Land” in accordance to one embodiment of the invention. The interactive surface  101  is imprinted with the design of the game racing board game “Candy Land”. The game requires no reading and minimal counting skills, making it suitable for young children. Due to the design of the game, there is no strategy involved-players are never required to make choices, just follow directions. The winner is predetermined by the shuffle of the cards. In this embodiment a player&#39;s figurine  603  is racing with an A.I. opponent&#39;s figurine  602 . This is a turn-based game and the process is as follows. 
         [0077]    A game starts once the player places his and the A.I. opponent&#39;s figurines  602 ,  603  on the “Start” square. The player then randomly picks up a number card  604  to see how many squares his figurine  603  can move up the path and proceeds to move his figurine by that number. Once the player has finished moving his figurine  603 , the A.I. then proceeds to move its figurine  602  up the path by a random number. Thus, a turn-based race is performed until a figurine arrives at the “finish” destination and a winner is declared. A speaker system  605  is affixed to the interactive surface  101  in order to provide audio feedback during gameplay. 
         [0078]    The system and method as illustrated in  FIG. 6  is similar to that described in the embodiment in  FIG. 5 . Thus, on an opponent&#39;s turn, the A.I. can direct the figurine  602  to move along the race path in such a manner that the figurine can move in a curved manner whenever it is moving along the race path bends. Referring back to  FIG. 6 , one can see the bold arrow numbered  608  illustrates the movement that the opponents  602  figurine will take along the curved path on its turn. In this scenario the figurine will move three squares forwards and realign itself as it proceeds along the path. As the figurine tackles this bend, the figurine will take a curved path and thus gradually rotate its orientation relative to the path so as to always face forwards along the path.