Patent Publication Number: US-2012025952-A1

Title: Identification system for human-machine interface using radio frequency and identification method for the same

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a human-machine interface and in particular relates to an identification system and an identification method for a human-machine interface. 
     2. Description of Prior Art 
     A human-machine interface (HMI), or a Human-machine Interface Device (HID) is a intermediate medium between operator and machine for performing information exchange. The operator uses control keys of the HMI or touch control icons of a touch control panel to trigger corresponding operations in order to make the machine control more convenient and practical. As a result, HMI makes the automatic industrial control a more convenient process. Further, HMI gradually replaces the conventional control panel which requires complicated wirings. 
     Currently, a HMI is used for controlling a plurality of machines and triggering serial operations or procedures of the machines and has significant impact on production lines. Therefore, it is desirable to perform strict controls over the HMI operations and assure that HMI operation is authorized. For example, different passwords are assigned with operating different authority levels to each operator and specific operations, such as tasks setting up critical system parameters or accessing to confidential data, require specific password for logging on to HMI. Thus, the operation confidentiality is improved and the risk of data leakage is reduced. 
     The HIM available in the market all utilize manual password input to perform the above mentioned operation control. Each operator has to manually input an identification password before operating on a HMI or switching to a specific operating screen in a HMI identification process. The operator is permitted to operate on the HMI or log on to specific operating screen of the HMI after the password input passes the identification process. 
     However, the above mentioned identification process using manual password input has the disadvantages described in the following: 
     1. When a user logs on to specific operating screen, the operation flow of the user is interrupted by manually input password, the user has to spend time on completing the password input step to move on with the operation flow which is inconvenient to the user. 
     2. An operator has to keep each password firmly in mind. In addition, if the operators is authorized with a plurality of passwords for logging on to a plurality of operating screens, the operator cannot log on to HMI and proceed with operations as scheduled once the operator forgets about the passwords; 
     3. Passwords may be eavesdropped to third party standing next to an operator when the operator manually input the password input. 
     To sum up, it is desired to provide an innovative identification system and method for an HMI to make an identification process ease of use, simple and without the risk of data leakage. 
     SUMMARY OF THE INVENTION 
     The objective of the present invention is to provide an identification system using radio frequency and identification method for a HMI. An identification process of the human-machine interface (HMI) is executed via sensing radio frequency identification (RFID) tag without manually input passwords. 
     To realize the above objective, according to the present invention, a computer senses a RFID tag and compiles a password table according to the tag number of the RFID tag. The password table is downloaded to the HMI. An identification process is executed at the HMI by sensing a RFID tag via a radio frequency card reader, looking up if matching tag number with the sensed RFID tag is recorded in the downloaded password table. If yes, HMI uses the identification password corresponding to the tad number in the password table for executing identification process. 
     Compare to the prior art, the present invention provides advantages that an administrator is allowed to assign an identification password and an operating authority to each RFID tag when configuring an operating screen of the HMI. The identification password and the operating authority are downloaded to the HMI along with the operating screen. Accordingly, the step sensing RFID tag is used for replacing manually input a password when a user desires to log on an HMI or instruct the HMI to switch to a particular operating screen. The user does not need to manually input the identification password such that the forget password scenario is avoided. Further, the risk of that the password is leaked to the third party as the user manually input the password is also avoided. 
    
    
     
       BRIEF DESCRIPTION OF DRAWING 
       The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself, however, may be best understood by reference to the following detailed description of the invention, which describes an exemplary embodiment of the invention, taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is an operating schematic diagram of a preferred embodiment according to the present invention; 
         FIG. 2  is a system block diagram of a preferred embodiment according to the present invention; 
         FIG. 3  is an configuring flow chart of a preferred embodiment according to the present invention; and 
         FIG. 4  is an identification flow chart of a preferred embodiment according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In cooperation with attached drawings, the technical contents and detailed description of the present invention are described thereinafter according to a preferable embodiment, being not used to limit its executing scope. Any equivalent variation and modification made according to appended claims is all covered by the claims claimed by the present invention. 
       FIG. 1  is an operating schematic diagram of a preferred embodiment according to the present invention. As shown in the diagram, the present invention is used in a human-machine interface (HMI)  1 . The HMI  1  is electrically connected to one or a plurality of mechanical equipments  2  for controlling series of automatic procedures of the mechanical equipments  2 . The HMI  1  is further electrically connected to a radio frequency card reader  3  for sensing a radio frequency identification (RFID) tag  4 . When an operator  40  desires to log on to the HMI  1  for executing operations, or instruct the HMI  1  to switch to a specific operating screen  10 , the HMI  1  senses the RFID tag  4  on the operator  40  via the radio frequency card reader  3  for executing identification process. The operator logs onto the HMI  1  or instruct the HMI  1  to switch to the specific operating screen  10  (for example, a screen assigning critical parameters or a browser screen having confidential data) after passing the identification process. 
       FIG. 2  is a system block diagram of a preferred embodiment according to the present invention. The identification system of the present invention comprises the HMI  1 , the radio frequency card reader  3  and a computer  5 . The computer  5  is electrically connected to the radio frequency card reader  3 . Additionally, a screen configuring application  50  is installed in the computer  5  for configuring the operating screen  10  of the HMI  1 . The computer  5  retrieves a tag number  41  of the RFID tag  4  via the radio frequency card reader. When configuring the operating screen  10 , a user can compile a password table T 1  at the same time. Upon the operating screen  10  is configured and the password table T 1  is compiled, the computer  5  is electrically connected to the HMI  1 , the completed operating screen  10  and the password table T 1  are downloaded to the HMI  1  and the operating screen  10  and the password table T 1  are saved in the HMI  1 . 
     The HMI  1  is connected to one or multiple mechanical equipments  2  and is further electrically connected to the radio frequency card reader  3 . When the HMI  1  proceeds to execute an identification process, the HMI  1  senses the RFID tag on the operator  40  (as shown in  FIG. 1 ) via the radio frequency card reader  3  for retrieving the tag number  41  recorded in the RFID tag  4 . The tag number  41  is compared with the tag numbers in the downloaded password table T 1  for executing identification process (detailed in the following). Upon the identification is completed, the operator  40  is permitted to log on to the HMI  1 , or instruct the HMI  1  to switch to the specific operating screen  10 . 
       FIG. 3  is an configuring flow chart of a preferred embodiment according to the present invention, According to the present invention, the password table T 1  is compiled in the computer  5  and downloaded to the HMI  1  for executing the identification process. Firstly, the computer  5  launches the screen configuring application  50  installed (step S 10 ), for configuring the operating screen  10  of the HMI  1 . Additionally, upon configuring the operating screen  10 , the method proceeds to step S 12  for compiling the password table T 1 . The step S 12  further comprises step S 120  to step S 126  detailed in the following. 
     The computer  5  senses the RFID tag  4  (step S 120 ) for retrieving the tag number  41  recorded in the RFID tag  4  via the radio frequency card reader  3  (step S 122 ). Following step S 122 , the computer  5  respectively assigns an identification password P 1  to each tag number  41  (step S 124 ) (as shown in the following table). In addition, each tag number  41  is respectively assigned an operating authority O 1  as required by the scenario (step S 126 ) (as shown in the following table). Depending on administrator&#39;s requirements, the password table T 1  records the tag number  41  and the identification password P 1 . Or, the password table T 1  records the tag number  41 , the identification password P 1  and the operating authority O 1 . In the following example, the password table T 1  records the tag number  41 , the identification password P 1  and the operating authority O 1 . It should be noted that the scope of the invention is not limited to the example. 
     Following the step S 12 , the computer  5  downloads the configured operating screen  10  along with the compiled password table T 1   a  to the HMI  1  (step S 14 ). 
     The computer  5  repeats executing the step S 12  for retrieving all tag numbers  41  of the RFID tag  4 . Further, the computer  5  respectively assigns the corresponding identification password P 1  and the operating authority O 1  for all tag numbers  41  in the password table T 1 . The password table T 1  is listed in the following: 
     
       
         
           
               
               
               
             
               
                   
               
               
                 tag 
                 identification 
                 operating 
               
               
                 number 41 
                 password P1 
                 authority O1 
               
               
                   
               
             
            
               
                 0 
                 123456 
                 1 
               
               
                 1 
                 abcdef 
                 2 
               
               
                 2 
                 123456 
                 1 
               
               
                 3 
                 XXXXXX 
                 3 
               
               
                   
               
            
           
         
       
     
     For example, the computer  5  senses four RFID tags  4  via the radio frequency card reader  3  and is acknowledged of the tag number  41  of the RFID tags  4  respectively as “0”, “1”, “2” and “3”. The computer  5  respectively assigns corresponding identification password P 1  and the operating authority O 1  to each tag number  41 . The corresponding identification password P 1  of the two RFID tags  4  having the tag number  41  as “0” and “2” is both assigned as “123456”. The computer  5  further assigns the corresponding operating authority O 1  of the two tag numbers  41  both as “1”. Accordingly, when the HMI  1  senses the two RFID tags  4 , the HMI uses exactly the same identification password P 1  for executing the identification process. Upon the identification process is completed, the same operating authority O 1  is generated. However, the example described above is one of the preferred embodiments, the password table T 1  can be assigned subject to user requirements. Also expressions of the tag number  41 , the identification password P 1  and the operating authority O 1  can vary as the developer desires and should not be limited thereto. 
       FIG. 4  is an identification flow chart of a preferred embodiment according to the present invention. The operating screen  10  and the password table T 1  generated by the computer  5  is received, saved and executed by the HMI  1 . When the HMI  1  proceeds to executing the identification process, the HMI  1  senses the RFID tag  4  via the radio frequency card reader  3  (step S 20 ) for retrieving the tag number  41  recorded in the RFID tag  4  (step S 22 ). Next, the HMI  1  compares the tag number  41  with tag numbers in the downloaded password table T 1  (step S 24 ), and determines if any tag number recorded in the password table T 1  matches the tag number  41  (step S 26 ). If there is not any tag number recorded in the password table T 1  matching with the tag number  41 , that indicates the RFID tag  4  is not assigned in step S 12 . As a result, the RFID tag  4  fails to pass the identification process. 
     Following step S 26 , if there is a tag number recorded in the password table T 1  matching with the tag number  41 , then the HMI  1  retrieves the identification password P 1  of the tag number  41  from the password table T 1  (step S 28 ). Also, following the step S 28 , the identification password P 1  is used for executing identification process of the HMI  1  (step S 30 ). Upon the identification is completed, the HMI  1  retrieves the operating authority O 1  corresponding to the tag number  41  from the password table T 1 , and the HMI is logged on according to the operating authority O 1  (step S 32 ), or instruct the HMI  1  to switch to the specific operating screen  10 . 
     As the skilled person will appreciate, various changes and modifications can be made to the described embodiments. It is intended to include all such variations, modifications and equivalents which fall within the scope of the invention, as defined in the accompanying claims.