KR19980074453A - Communication system and method for multi robot control - Google Patents

Abstract

The present invention relates to a communication system and method for multi-robot control, in particular, receiving means for receiving data serially from an external device; Main process means for checking whether data is received by the receiving means at predetermined time intervals after initialization, receiving a received byte for a predetermined byte, detecting a service number, and calling a subprocess according to the detected service number; Receive the robot identifier from the main process to the corresponding sub-process when calling by the main process means, receive data directly from the receiving means, wait for a predetermined time according to the presence or absence of the received data and control code character, A plurality of subprocess means for transmitting the resultant response data according to the received data; And transmission means for sequentially determining the transmission order of response data received from the sub-process means.

Therefore, the present invention separates the receiving module and the transmitting module and transmits and receives simultaneously, thereby enabling faster communication. By specifying only the identifier of the robot to be controlled, it is possible to control several robots and to lock the transmission. By controlling the transmission order by the function, the crosstalk of data can be eliminated.

Description

Communication system and method for multi robot control

The present invention relates to a communication system and method for multi-robot control, and in particular, a communication for multi-robot control implemented with a serial communication algorithm to enable stable exchange of information with a plurality of robots using a serial communication port of a single line. System and method.

In general, in the case of controller communication, the load applied to the controller varies according to the communication initiation side, that is, the controller or external device. In no case should the controller be affected by it by performing serial communication such as motion, TP communication, Ethernet communication, location data editing, robot program editing, etc. To this end, a technique for optimizing the communication processor in the controller is required.

Conventional robot communication connects one processor and a work robot by serial input / output lines so that the work robot performs necessary work according to a command provided by an external device such as a personal computer by one-to-one communication. This prior art does not require the distribution of data or additional communication by other processes during communication. In the case of a multitasking multitasking system, the above necessity has arisen, but in most cases, a method of waiting for communication by a non-communicable process is used.

The robot communication performs a relatively simple operation such as file exchange and position data exchange with a single robot.

The communication steps according to the prior art are roughly listed in order, firstly, confirming a connection, secondly, transmitting a token, i.e., a service number, for a service request, and thirdly, a plurality of bytes for a work command. Transmit data, and confirm response according to the data, and finally terminate communication.

However, the above-described conventional technique is applied only to a single robot, and when an error occurs during communication, a countermeasure, that is, a time check, a power reset, etc., is passive, and a communication failure occurs when the contents are interrupted during data transmission. There is a problem that the error handling only after about 30 seconds.

SUMMARY OF THE INVENTION An object of the present invention is to provide a communication system and method for multi-robot control which enables stable information exchange with a plurality of robots using only a serial communication port of a single line to solve the above problems.

Another object of the present invention is to provide a method that does not interfere with the smooth control of the robot due to communication.

In order to solve the above problems, the system of the present invention comprises: receiving means for receiving data serially from an external device; Main process means for checking whether data is received by the receiving means at predetermined time intervals after initialization, receiving a received byte for a predetermined byte, detecting a service number, and calling a subprocess according to the detected service number; Receive the robot identifier from the main process to the corresponding sub-process when calling by the main process means, receive data directly from the receiving means, wait for a predetermined time according to the presence or absence of the received data and control code character, A plurality of subprocess means for transmitting the resultant response data according to the received data; And transmission means for sequentially determining the transmission order of response data received from the sub-process means.

In order to solve the above problems, the method of the present invention comprises the steps of receiving data serially from an external device and latching the received data; Initializing the main process; Checking the latched data at a predetermined time interval when it is initialized, and determining whether there is received data to cancel loading of the central processing unit when there is no received data; Sequentially reading only predetermined bytes from the head of the received data to the main process when the received data exists; Detecting a service number by checking a type of the received data read in the step; A service call step of calling a corresponding function among a plurality of functions for robot control according to the service number; Reading the remaining data of the received data when the function is called, and performing a predetermined subprocess according to the read data; And transmitting the response data generated by performing the subprocess to an external device in a function call order.

1 is a block diagram illustrating a communication system for multi-robot control according to the present invention.

2 is a flowchart for explaining a communication method for multi-robot control according to the present invention.

3 is a flowchart for explaining a subprocess in the service call according to the present invention.

4 is a flowchart for explaining a transmission method in the transmission module according to the present invention.

5 is a view for explaining a communication protocol processed in the main process according to the present invention.

6 is a diagram for explaining a communication protocol processed in a subprocess according to the present invention;

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram illustrating a communication system for multi-robot control according to the present invention, as shown, a transmission module 10, a main process 20, a plurality of sub-processes (F1 to Fn), It consists of a transmission module (40).

The operation of the communication system for multi-robot control according to the present invention configured as described above will be described with reference to the flowcharts of FIGS. 2, 3 and 4 and the communication protocols of FIGS. 4 and 5 as follows.

Referring to FIG. 1, a communication method for multi-robot control according to the present invention transmits and receives data through a serial data transmission line from an external device such as a personal computer (PC) to achieve a desired robot control. . Normally, communication between the external device and the communication process is made by the device driver 60. The role of the device driver 60 is to inform the operating system how to control and manage peripheral devices.

Referring to FIG. 2, each robot performing a specific task is assigned its own unique number. In order for the robot to perform the task, the programmer designates only the identification number of the robot through the external device. do. Once programmed data including the token (service start number) and the robot identifier (Robot #) are transmitted and latched in the buffer of the receiving module (step 10).

Then, if a robot identifier is specified, the main process initializes the serial communication port RS232C to use the serial communication device driver (step 10).

After the twelfth step, the main process checks the buffer of the receiving port at a time interval of 50 ms to determine whether data is received in the buffer. As a result of the determination, if the received data does not exist, the thread_yield is executed to release the load of the central processing unit and terminate the communication (step 14). In contrast, if the received data exists, The received data latched in the buffer is read in units of 1 byte, and the head of the received valid data is found to sequentially read only predetermined bytes into the main process (step 18).

The head is an inquiry character (ENQ) or a head start character (SOH). Enumerating the control characters for robot control used in the present invention, inquiry character (ENQ), acknowledgment (ACK), head start character (SOH), text start character (STX), data end character (GS), text There is an end character (ETX), end-of-transmission character (EOT), and each of these data is defined in the standard ASCII code table as an ASCII code byte.

As shown in FIG. 5, the main process reads out a communication protocol composed of a head start character (SOH), a service start number (token), error control characters (errorH, errorH), and a robot identifier (Robot #). After reading the head start character (SOH) which is the leading data, the data are read sequentially. Here, initial errorH and errorL are 0 (zero), respectively, and it is Ox30 as ASCII coat.

In this case, when the head data is an inquiry character (ENQ), an acknowledgment character (ACK) is transmitted through the transmission module (Tx).

Subsequently, the main process checks the received types of data, extracts the token, that is, the service number, and checks the extracted token (step 18).

The communication process according to the present invention can perform about 60 functions, and all functions are performed by separate function calls. Therefore, after the eighteenth step, a service call for calling the corresponding function is performed according to the checked token (step 20).

When receiving a service call in the twentieth step, as shown in FIG. 5, the remaining received data not processed in the main process is passed to the process performed by the service call from the left to the right side of the drawing, and the robot number is transmitted from the main process In operation 22, a predetermined subprocess is performed according to the remaining received data. At this time, the main process becomes free and prepares for the next process.

The reception data of FIG. 6 is composed of n data and control characters GS, CSH, CSL, and ETX, GS is the end of the data, CSH is the high byte of the check sum, and CSL is the check sum. ) Indicates the lower byte, respectively, and the end-of-text character (ETX) is regarded as the last received byte, and when the end-of-text character (ETX) is received, an end-of-transmission (EOT) byte is transmitted through the transmitting module.

The response data generated by the execution of the subprocess is transmitted to the external device through the transmission module in the function call order (step 24).

Hereinafter, the subprocess performed by the service call step will be described in detail.

Referring to FIG. 2, when the service is called by the main process, the subprocess receives the robot identifier from the main process (step 30), and then reads the received data latched in the buffer from the external device directly into the corresponding function of the subprocess. (Step 32).

As a result of performing step 32, it is determined whether data reading is properly performed (step 34).

After the thirty-fourth step, if data is not received for five seconds, error processing is performed and the process returns to the main process (stage 36). If control characters such as GS, ESC, ETX, etc. are received within 5 seconds, error processing is performed and the process returns to the main process (step 38).

Subsequently, when data is read and the control code character is not read, a predetermined subprocess is performed according to the read jitter, and the response data generated thereby is sent to the transmission module Tx (step 40).

Therefore, based on the received data, the control right of the communication process is transferred to the sub-process for controlling the robot, the loss of data is sensed during communication, and the communication is forcibly terminated according to the loss of data.

Hereinafter, the operation of the transmission module according to the present invention will be described.

Some communication modules may initiate communication by a command of the robot program. That is, when the external device wants to receive data, it sends out ENQ through the transmission module Tx and expects a response acknowledgment character (ACK).

The above subprocesses can be executed simultaneously by a plurality of function calls, but in order to transmit the response data to the external device, they must be transmitted one by one.

Referring to FIG. 4, first, a transmission identifier is assigned to each response data in order to determine a transmission order of response data generated when a function call is made according to a process request order (step 60). To this end, the current identifier is incremented by 1 to determine the transmission identifier of each response data.

After the 60th step, it is determined whether the transmission identifier of the response data to be transmitted is matched with a preset next order value (step 62).

On the other hand, if the result of the determination matches, the mutex is checked. If the mutex is locked, the mutex is delayed for a predetermined time and the mutex is checked again (step 64). . Here, the mutex performs a lock when an arbitrary process uses the transmission module Tx to block another processor from entering.

On the other hand, when the standby state is released, the response data is transmitted, the mutex is locked so that other response data does not enter the transmission module, and the formatted data is transmitted to the external device (step 66).

After transmitting in step 46, the next order value is incremented and updated by one, and the mutex is released to allow the next response data to enter the transmission module (step 68).

As described above, the present invention separates the receiving module from the transmitting module and manages them in separate processes so that transmission and reception occur simultaneously. Therefore, faster communication is possible, and only the identifier of the robot that the programmer wants to control through a single personal computer is designated. By doing so, it is possible to control several robots and to control the transmission order by the transmission lock function, thereby eliminating crosstalk of data.

In addition, in the present invention, there is another effect that the error processing time can be shortened by waiting for a predetermined time when the communication field occurs or forcibly terminating by error processing after a specific event occurs.

Claims (7)

Receiving means for receiving data serially from an external device; Main process means for checking whether data is received by the receiving means at predetermined time intervals after initialization, receiving a received byte for a predetermined byte, detecting a service number, and calling a subprocess according to the detected service number; Receive the robot identifier from the main process to the corresponding sub-process when calling by the main process means, receive data directly from the receiving means, wait for a predetermined time according to the presence or absence of the received data and control code character, A plurality of subprocess means for transmitting the resultant response data according to the received data; And transmission means for sequentially determining the transmission order of the response data received from the sub-process means and sequentially transmitting the response data. A receiving step of receiving data serially from an external device and latching the received data; Initializing the main process; Checking the latched data at a predetermined time interval when it is initialized, and determining whether there is received data to cancel loading of the central processing unit when there is no received data; Sequentially reading only predetermined bytes from the head of the received data to the main process when the received data exists; Detecting a service number by checking a type of the received data read in the step; A service call step of calling a corresponding function among a plurality of functions for robot control according to the service number; Reading the remaining data of the received data when the function is called, and performing a predetermined subprocess according to the read data; And transmitting response data generated by performing the subprocess to an external device in a function call order. The communication method according to claim 2, wherein the main process initialization step performs an initialization operation twice and escapes when the main process fails more than two times. The communication protocol of the received data processed in the main process comprises a head start character (SOH), a service start number (token), error control characters (errorH, errorH), and a robot identifier. Communication method for multi-robot control, characterized in that. The communication method according to claim 2, wherein the presence or absence of received data in the main process is performed at 50 ms intervals. The method of claim 2, wherein the subprocess comprises: receiving a robot identifier from a main process, directly reading data received from an external window into a corresponding function, and determining whether to receive data when reading data; And an error process when no data is received for a predetermined time as a result of the determination of the step, returning to the main process, and determining whether a predetermined control code character exists in the received data path when receiving the data; Error control and return to the main process if the control code character is present, and if there is no control code character when receiving data, performs a predetermined process according to the received data, and sends the response data generated by the transfer module Communication method for multi-robot control, characterized in that consisting of the sending step. 3. The method of claim 2, wherein the transmitting step comprises: assigning a transmission identifier to the response data to determine a transmission order of each response data sent from a plurality of subprocesses according to a subprocess request order; Determining whether the transmission identifier of the response data to be transmitted is matched with a preset next order value; Waiting if the determination result of the step does not match; Performing a mutex lock check if there is a match, and if the mutex is locked, delaying response data to be transmitted for a predetermined time and checking the mutex again; Formatting response data to be transmitted when the mutex is released, locking the mutex, and transmitting the response data; And releasing the mutex to update the next sequence value after transmitting and to release the next sequence of response data into the transmission module.