200933184 九、發明說明： 【發明所屬之技術領威】 本發明是有關/種移動式電子裝置尋找定點之方法及 系統，特別是—種移動式電子裝置利用音頻訊號尋找疋點之 方法及系統。 【先前技術】 近年來，由於移動式電子裝置之自主性提高’因此移動 ® 式電子裝置已逐漸應用於人們的生活當中，例如自動式吸塵 器等。移動式電子裝置必須能夠自行移動至一基座進行充電 或其它操作，方可提昇移動式電子裝置的自主性並擴大其應 用範圍。 習知之移動式電子裝置尋找基座的方法有雷射掃描 器、攝影機、射頻識別系統（Radio Frequency Identification， HFID)、輪式編碼系統、無線區域網路(wireless Local Area Network，WLAN)以及超音波感測器等。然而，上述尋找基 φ 座的方法皆有各自的缺點需要改進。例如，雷射掃描器雖具 備高準確度，但其成本昂貴，不適合普及於一般家庭；攝影 機需事先針對各別的環境建構系統，且容易受光線變化的影 響；RFID亦需事先在多個位置上設置標籤（tag);輪式編碼系 統容易因輪子打滑而累積誤差；WLAN相較於其它習知方 法，其疋位精度相對較差；超音波感測器的波長短，易被環 境所吸收，因此不適合應用於家庭等相對複雜的環境。 综上所述，如何使移動式電子裝置以成本較為低廉的硬 體設備即可尋找出設置基座蚊點，且其可直接應用於各種 不同的環境便是目前極需努力的目標。 200933184 【發明内容】 針對上述問題，本發明目的之一是提供一種移動式電子 裝置尋找定點之方法及系統，其是於一定點發射一音頻訊 _ 號，移動式電子裝置即可利用音頻訊號找出定點，因此其硬 體設備的成本較為低廉，且可直接應用於各種不同的環境。 為了達到上述目的，本發明一實施例之移動式電子裝置 尋找定點之方法包含：一音頻發射單元於一定點發射一音頻 訊號；以及一移動式電子裝置以至少二個音頻接收單元接收 Ο 音頻訊號，並計算出音頻訊號之方位角0，方位角0是由下列 公式計算而得： Θ » sin'1 —200933184 IX. Invention Description: The present invention relates to a method and system for finding a fixed point for a mobile electronic device, and more particularly to a method and system for a mobile electronic device to find a defect using an audio signal. [Prior Art] In recent years, the mobility of mobile electronic devices has increased. Therefore, mobile ® electronic devices have been gradually applied to people's lives, such as automatic vacuum cleaners. Mobile electronic devices must be able to move to a pedestal for charging or other operations to increase the autonomy of the mobile electronic device and expand its range of applications. Conventional mobile electronic devices find a pedestal by a laser scanner, a camera, a radio frequency identification (HFID), a wheel coding system, a wireless local area network (WLAN), and an ultrasonic wave. Sensors, etc. However, the above methods for finding the base φ seat have their respective disadvantages and need to be improved. For example, laser scanners are highly accurate, but they are expensive and are not suitable for general households. Cameras need to be built in advance for each environment and are susceptible to light changes. RFID must also be in multiple locations. The tag is set on the wheel; the wheel coding system is easy to accumulate errors due to wheel slip; WLAN has relatively poor clamping accuracy compared to other conventional methods; the ultrasonic sensor has a short wavelength and is easily absorbed by the environment. Therefore, it is not suitable for use in relatively complex environments such as homes. In summary, how to make mobile electronic devices find the base mosquitoes with low-cost hardware devices, and its direct application to various environments is currently the goal of hard work. In view of the above problems, one of the objects of the present invention is to provide a method and system for finding a fixed point of a mobile electronic device, which is to transmit an audio signal at a certain point, and the mobile electronic device can use the audio signal to find The fixed point, so the cost of its hardware equipment is relatively low, and can be directly applied to a variety of different environments. In order to achieve the above object, a method for finding a fixed point of a mobile electronic device according to an embodiment of the present invention includes: an audio transmitting unit transmitting an audio signal at a certain point; and a mobile electronic device receiving an audio signal at least two audio receiving units. And calculate the azimuth of the audio signal 0, the azimuth 0 is calculated by the following formula: Θ » sin'1 —
D 其中，D為二個音頻接收單元間之距離，L為音頻訊號 分別抵達二個音頻接收單元之距離差。 為了達到上述目的，本發明一實施例之移動式電子裝置 尋找定點之系統包含一音頻發射單元以及一移動式電子裝 置。音頻發射單元用以於一定點發射一音頻訊號。移動式電 子裝置包含至少二個音頻接收單元以及一控制單元。音頻接 Q 收單元用以接收音頻訊號，控制單元則與音頻接收單元電性 連接，並依據音頻訊號以前述公式計算出音頻訊號之方位角 θ 。 以下藉由具體實施例配合所附的圖式詳加說明，當更容 易瞭解本發明之目的、技術内容、特點及其所達成之功效。 【實施方式】 請參照圖1，本發明之一較佳實施例之移動式電子裝置尋找 定點之系統包含一音頻發射單元11以及一移動式電子裝置 200933184 η。音頻發射單元η設置於—定點，例如—基座卜 發射一音頻訊號。移動式電子裝置12 ^ _ 上°又有至少二個音頻接 收早疋⑵以及-控制單元122。音頻接收單元⑵用以= ，音頻發射單元11所發射的讀訊號，舉例而言，其 麥克風。控制單元122則與音頻接收單元121電性連: 5十算出音頻訊號來源的方位角0。 ❹ 如a 1所示，方位角θ是指音頻接收單元121間連線之 ^線與音頻訊號來源方向的夾角’方位角0與音頻接收 12ι間之距離的關係可由下列公式表示： c〇s(9O-^) = sin(0) 元D where D is the distance between two audio receiving units, and L is the distance difference between the audio signals and the two audio receiving units respectively. In order to achieve the above object, a system for finding a fixed point of a mobile electronic device according to an embodiment of the present invention includes an audio transmitting unit and a mobile electronic device. The audio transmitting unit is configured to transmit an audio signal at a certain point. The mobile electronic device includes at least two audio receiving units and a control unit. The audio receiving unit is configured to receive the audio signal, and the control unit is electrically connected to the audio receiving unit, and the azimuth angle θ of the audio signal is calculated according to the audio signal according to the foregoing formula. The purpose, technical contents, features and effects achieved by the present invention will be more readily understood from the following detailed description of the embodiments. [Embodiment] Referring to FIG. 1, a system for finding a fixed point of a mobile electronic device according to a preferred embodiment of the present invention includes an audio transmitting unit 11 and a mobile electronic device 200933184 η. The audio transmitting unit η is disposed at a fixed point, for example, the pedestal transmits an audio signal. The mobile electronic device 12^_upper has at least two audio receptions (2) and a control unit 122. The audio receiving unit (2) is used for =, the read signal transmitted by the audio transmitting unit 11, for example, its microphone. The control unit 122 is electrically connected to the audio receiving unit 121: 50 calculates the azimuth angle 0 of the audio signal source. ❹ As shown in a1, the azimuth angle θ refers to the angle between the line connecting the audio receiving unit 121 and the direction of the audio signal source. The relationship between the azimuth angle 0 and the audio receiving distance 12ι can be expressed by the following formula: c〇s (9O-^) = sin(0)
L \-- D 其中’D為音頻接收單元121間之距離，L為音頻訊於 /刀別抵達二個音頻接收單元121之距離^。於—實施例中广 L值可由下列公式計算而得：L \-- D where 'D is the distance between the audio receiving units 121, and L is the distance from the audio signal to the two audio receiving units 121. In the embodiment, the wide L value can be calculated by the following formula:
L = T X CL = T X C
其中，τ為同一音頻訊號抵達二個音頻接收單元ΐ2ι的 時間差:C為音頻訊號的速度。舉例而言，以—般交又相關 (generalized cross c〇rrelati〇n，Gcc)方法計算同一音頻訊號 的相位延遲而得T值。當移動式電子裝置12取得方位角0 後，移動式電子裝置12往方㈣Θ的方向旋轉θ度即可正對 音頻發射單元11，亦即基座1所在的定點。 清參照圖2，說明本發明之一較佳實施例之移動式電子裝 置尋找定點之方法。首先，一音頻發射單元11於一定點發射 一音，訊號（S21)。接著，移動式電子裝置12即以二個音頻 接收單元121接收音頻訊號，並計算出音頻訊號來源的方位 角1(S22)。得知音頻訊號來源的方位後，移動式電子裝置12 僅需往方位角0方向旋轉0度即可找到設置音頻發射單元 的疋點十舁方位角0的方法如前所述，在此不再贅述。 200933184 在較為複雜的環境中，移動式電子裝置12可能受到環 境因素而影響計算方位角β的結果。舉例而言，音頻訊號可 能受到噪音的干擾，使得移動式電子裝置12無法取出可信賴 的音頻訊號以計算方位角0 ;音頻訊號可能經過反射後才由 •音頻接收單元121所接收，使得移動式電子裝置12誤認音頻 、訊號的反射點為定點；音頻發射單元11與移動式電子裝置 12之間有障礙物，導致音頻訊號產生繞射現象，使得移動式 電子裝置12計算的方位角<9有誤。 針對上述環境因素的影響，於一較佳實施例中，音頻訊 © 號是以一預定週期間歇性地發射出去，移動式電子裝置12 即可在有噪音的環境下擷取出可信賴的音頻訊號來計算方位 角0。較佳者，音頻訊號可為包含多個頻率的音頻訊號，如 此可進一步減低噪音的干擾。此外，由於音頻訊號經反射到 達音頻接收單元121有較長的路徑，因此移動式電子裝置12 可僅擷取一預定初始時間内的音頻訊號來計算方位角0，以 降低反射音頻訊號影響計算方位角0的結果。 請再參照圖2,本發明之移動式電子裝置尋找定點之方法 更包含判斷音頻發射單元11與移動式電子裝置12之間是否 © 有障礙物的步驟（S23)。若音頻發射單元11與移動式電子裝 置12之間無障礙物，即表示移動式電子裝置已正對音頻發射 單元11(S24)。反之，若音頻發射單元11與移動式電子裝置 12之間有障礙物，控制單元122即執行一預定的移動策略 (S25)，使移動式電子裝置12脫離有障礙物的區域。 請參照圖3,說明判斷音頻發射單元11與移動式電子裝 " 置12之間是否有障礙物的方法。首先，接收音頻訊號並計算 - 出方位角0 (S31)，接著，往方位角0的方向旋轉90度（S32)。 之後，再次接收音頻訊號並計算出方位角（9 (S33)，再往方位 200933184 角θ的：向旋㈣度(S34)。接收音頻訊號並計算出方位角θ L:二較方位角0是否小於一閥值(S36)，例如度。 上得到的方位角Θ小於閥值，即表示音頻發射單元 11與移動式電子裝置12之間無障礙物(S37)。 接續上述說明，若此時計算得到的方位角0大於等於間 ^即以步驟㈣來判斷上述步驟是否已執行—預定次數 覆步驟S31〜S36。若步驟S31〜s36已重覆執行一 音頻發鼾。又如3次)後方位角0仍大於等於閥值，即表示Where τ is the time difference between the arrival of the same audio signal and the two audio receiving units ΐ2: C is the speed of the audio signal. For example, the phase delay of the same audio signal is calculated by the generalized cross c〇rrelati〇n (Gcc) method to obtain a T value. When the mobile electronic device 12 obtains the azimuth angle 0, the mobile electronic device 12 rotates θ degrees in the direction of the square (four) 即可 to face the audio transmitting unit 11, that is, the fixed point where the susceptor 1 is located. Referring to Fig. 2, a method of finding a fixed point of a mobile electronic device in accordance with a preferred embodiment of the present invention will be described. First, an audio transmitting unit 11 emits a tone, signal (S21) at a certain point. Next, the mobile electronic device 12 receives the audio signal by the two audio receiving units 121, and calculates the azimuth angle 1 of the audio signal source (S22). After knowing the orientation of the audio signal source, the mobile electronic device 12 only needs to rotate 0 degrees in the azimuth direction to find the method of setting the azimuth angle of the audio transmitting unit. As described above, it is no longer Narration. 200933184 In a more complex environment, mobile electronic device 12 may be affected by environmental factors that affect the calculation of azimuth β. For example, the audio signal may be disturbed by noise, so that the mobile electronic device 12 cannot take out the trusted audio signal to calculate the azimuth 0; the audio signal may be reflected and received by the audio receiving unit 121, so that the mobile The electronic device 12 misidentifies the reflection point of the audio and the signal as a fixed point; there is an obstacle between the audio transmitting unit 11 and the mobile electronic device 12, causing the audio signal to be diffracted, so that the azimuth calculated by the mobile electronic device 12 <9 mistaken. In response to the above-mentioned environmental factors, in a preferred embodiment, the audio signal number is intermittently transmitted at a predetermined period, and the mobile electronic device 12 can extract the trusted audio signal in a noisy environment. To calculate the azimuth 0. Preferably, the audio signal can be an audio signal comprising a plurality of frequencies, which further reduces noise interference. In addition, since the audio signal has a long path after being reflected to the audio receiving unit 121, the mobile electronic device 12 can only calculate the azimuth angle by using an audio signal of a predetermined initial time to reduce the reflected audio signal to affect the calculated orientation. The result of the angle 0. Referring to FIG. 2 again, the method for finding a fixed point of the mobile electronic device of the present invention further includes the step of determining whether there is an obstacle between the audio transmitting unit 11 and the mobile electronic device 12 (S23). If there is no obstacle between the audio transmitting unit 11 and the mobile electronic device 12, it means that the mobile electronic device has been facing the audio transmitting unit 11 (S24). On the other hand, if there is an obstacle between the audio transmitting unit 11 and the mobile electronic device 12, the control unit 122 executes a predetermined movement strategy (S25) to disengage the mobile electronic device 12 from the obstacled area. Referring to Fig. 3, a method of determining whether there is an obstacle between the audio transmitting unit 11 and the mobile electronic device 12 will be described. First, the audio signal is received and the azimuth angle 0 (S31) is calculated, and then rotated 90 degrees in the direction of the azimuth angle 0 (S32). After that, the audio signal is received again and the azimuth angle is calculated (9 (S33), and then the direction 200933184 angle θ: the direction of rotation (four degrees) (S34). The audio signal is received and the azimuth angle θ L is calculated: whether the azimuth angle 0 is Less than a threshold value (S36), for example, degree. The obtained azimuth angle Θ is smaller than the threshold value, that is, the obstacle between the audio transmitting unit 11 and the mobile electronic device 12 (S37). The obtained azimuth angle 0 is greater than or equal to ^, that is, the step (4) is used to judge whether the above step has been performed - the predetermined number of steps S31 to S36 are repeated. If the steps S31 to s36 have repeatedly performed an audio clock, another step is as follows: Angle 0 is still greater than or equal to the threshold, which means
^咅I早70 11與移動式電子裝置12之間有障礙物(S39)。 f注，者，步驟SM〜S36的重覆執行次數可依設計自行設 疋’其至少為1次。 ，參照圖4 ’若音頻接收單元121不具有方向性，則計 之方位角可能為01或02。在此情形下，移動式電子 2 2便有可能朝向錯誤的音頻發射單元11，移動。針對此 立頻接^具有方向性的音頻接收單元121，或設置第三個 二接收早7C 121使三個音頻接收單元121呈三角配置即可 硬需注意者’依據圖3所示之流程，其可以較低的 硬體成本來解決如圖4所示的問題。 凊參照圖5a以及圖5b’說明判斷音頻發射單元u與移 裝置12之間是否有障礙物的另__方法。假設音頻訊 ^為包3頻率六個頻率的音頻訊號，如圖^所示，若 二：發射單元11與移動式電子裝置12之間無障礙物，亦即 =兄較為單純時，賴取任—頻率之音頻訊號所計算得到的 立角會相近於所有頻率之音頻訊號計算所得的方位角平均 值，如圖5a中之虛線所示。 反之’若移動式電子裝置12被障礙物所阻擔時，由於 不同頻率之音頻訊號在空氣令傳播的波長不同，受到繞射影 200933184 響的結果各有不同，因此，擷取每一頻率計算所得之方位角 間之變異較大，如圖5b所示。因此，於一實施例中，可於移 動式電子裝置12中設置一儲存單元（未圖示），其與控制單元 122電性連接，並於其中儲存一聲場資料。聲場資料可事先 以模擬的方式取得。舉例而言，開發者事先模擬許多有/無障 礙物的情況，以取得如圖5a及圖5b的結果，再以統計學習 的方法，例如支持向量機（support vector machine) ’來區分有 /無障礙物。如此，控制單元122即可將音頻訊號與儲存單元 中之聲場資料作比較，以判斷移動式電子裝置12與音頻發射 單元11間是否有障礙物。 需注意者，上述兩種判斷是否有障礙物的方法不僅可單 獨實施，亦可兩者組合實施。舉例而言，控制單元122可將 擷取之資料與事先儲存的聲場資料比較來判斷是否有障礙 物，若有，則執行預定的移動策略。若無，則再執行圖3所 示之流程，再次判斷是否有障礙物，若有，則執行預定的移 動策略；若無，則表示移動式電子裝置12已正對音頻發射單 元11。 於上述實施例中，音頻發射單元11可設置於一基座1， 移動式電子裝置12即依據音頻發射單元11發出之音頻訊號 移動至基座1來進行充電或其它操作。舉例而言，音頻發射 單元11可為一揚聲器或是喇队；移動式電子裝置12可為一 機器人，例如一移動式吸塵器。然而，移動式電子裝置12 亦可依據使用者發出的聲音找出並移動到使用者的位置，舉 例而言，移動式電子裝置12可為一電子寵物。 綜合上述，本發明之移動式電子裝置尋找定點之方法及系 統以電聲元件（例如喇队及麥克風）即可使移動式電子裝置找 10 200933184 出預設的定點，因此其硬體成本相對較為便宜，且無須事先 設定即可直接應用於各種不同的環境。 以上所述之實施例僅是為說明本發明之技術思想及特 點，其目的在使熟習此項技藝之人士能夠瞭解本發明之内容 並據以實施，當不能以之限定本發明之專利範圍，即大凡依 本發明所揭示之精神所作之均等變化或修飾，仍應涵蓋在本 發明之專利範圍内。 Ο 11 200933184 【圖式簡單說明】 圖1為一示意圖，本發明一較佳實施例之移動式電子裝置尋找定 點之系統。 '圖2為一流程圖，顯示本發明一較佳實施例之移動式電子裝置尋 找定點之方法。There is an obstacle between the 70I early 70 11 and the mobile electronic device 12 (S39). f Note, the number of repeated executions of steps SM to S36 can be set by the user's at least one time. Referring to Fig. 4', if the audio receiving unit 121 does not have directivity, the azimuth may be 01 or 02. In this case, it is possible for the mobile electronic 2 2 to move toward the wrong audio transmitting unit 11. For the audio receiving unit 121 having the directivity of the vertical frequency connection, or setting the third two receiving early 7C 121, the three audio receiving units 121 are arranged in a triangle, which can be hardly noticed, according to the flow shown in FIG. It can solve the problem shown in Figure 4 at a lower hardware cost. Further, another method of judging whether there is an obstacle between the audio transmitting unit u and the shifting device 12 will be described with reference to Figs. 5a and 5b'. Assume that the audio signal is an audio signal with a frequency of six frequencies of the packet 3 frequency, as shown in FIG. 2, if the second between the transmitting unit 11 and the mobile electronic device 12 is unobstructed, that is, if the brother is relatively simple, - The calculated angle of the audio signal of the frequency will be similar to the azimuth average calculated from the audio signals of all frequencies, as indicated by the dashed line in Figure 5a. Conversely, if the mobile electronic device 12 is blocked by an obstacle, since the audio signals of different frequencies are different in the wavelength of the air, the results of the diffraction shadow 200933184 are different, so the calculation of each frequency is obtained. The variation between azimuths is large, as shown in Figure 5b. Therefore, in an embodiment, a storage unit (not shown) can be disposed in the mobile electronic device 12, which is electrically connected to the control unit 122 and stores a sound field data therein. Sound field data can be obtained in advance by simulation. For example, the developer simulates a number of situations with/without obstacles in advance to obtain the results as shown in Figures 5a and 5b, and then uses statistical learning methods such as support vector machine to distinguish between yes and no. obstacle. In this manner, the control unit 122 can compare the audio signal with the sound field data in the storage unit to determine whether there is an obstacle between the mobile electronic device 12 and the audio transmitting unit 11. It should be noted that the above two methods for judging whether there are obstacles can be implemented not only individually but also in combination. For example, the control unit 122 may compare the captured data with the previously stored sound field data to determine whether there is an obstacle, and if so, execute a predetermined movement strategy. If not, the flow shown in Fig. 3 is executed again to determine whether there is an obstacle, and if so, a predetermined movement strategy is executed; if not, it indicates that the mobile electronic device 12 is facing the audio transmitting unit 11. In the above embodiment, the audio transmitting unit 11 can be disposed on a pedestal 1, and the mobile electronic device 12 moves to the pedestal 1 according to the audio signal sent by the audio transmitting unit 11 for charging or other operations. For example, the audio transmitting unit 11 can be a speaker or a racquet; the mobile electronic device 12 can be a robot, such as a mobile vacuum cleaner. However, the mobile electronic device 12 can also find and move to the user's location according to the sound emitted by the user. For example, the mobile electronic device 12 can be an electronic pet. In summary, the method and system for finding a fixed point of the mobile electronic device of the present invention can make the mobile electronic device find a predetermined fixed point by using an electroacoustic component (such as a racquet and a microphone), so that the hardware cost is relatively relatively high. It is cheap and can be directly applied to a variety of different environments without prior setting. The embodiments described above are only intended to illustrate the technical idea and the features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the contents of the present invention and to implement the present invention. That is, the equivalent variations or modifications made by the spirit of the present invention should still be included in the scope of the present invention. Ο 11 200933184 [Simplified Schematic] FIG. 1 is a schematic diagram of a system for finding a fixed point of a mobile electronic device according to a preferred embodiment of the present invention. Figure 2 is a flow chart showing a method of finding a fixed point of a mobile electronic device in accordance with a preferred embodiment of the present invention.
I 圖3為一流程圖，顯示本發明較佳實施例之一判斷是否有障礙物 之方法。 圖4為一示意圖，顯示本發明一較佳實施例之移動式電子裝置尋 © 找定點之系統可能誤判之情形。 圖5a及圖5b為一示意圖，顯示本發明較佳實施例之另一判斷是否 有障礙物之方法。 【主要元件符號說明】 1 基座 11 ' 1Γ 音頻發射單元 12 移動式電子裝置 121 音頻接收單元 122 控制單元 S21 〜S25 移動式電子裝置尋找定點之流程 S31-S39 判斷是否有障礙物之流程 12Figure 3 is a flow chart showing a method of determining whether there is an obstacle in one of the preferred embodiments of the present invention. FIG. 4 is a schematic diagram showing a possible misjudgment of the system for finding a fixed point in the mobile electronic device according to a preferred embodiment of the present invention. Figures 5a and 5b are schematic views showing another method of determining whether there is an obstacle in accordance with a preferred embodiment of the present invention. [Main component symbol description] 1 Base 11 ' 1 音频 Audio transmitting unit 12 Mobile electronic device 121 Audio receiving unit 122 Control unit S21 ~ S25 Mobile electronic device to find fixed point process S31-S39 Process for determining whether there is obstacle 12