KR20110030191A - Apparatus and method for robot control based network - Google Patents

Abstract

PURPOSE: A network-based robot control method and an apparatus thereof are provided to prevent the performance degradation of the whole network and to maintain the time agreement about the operation of a master controller and a sub controller. CONSTITUTION: A calculation unit(203) calculates the propagation delay and time offset of the sub controller. A time agreement control unit(202) coincides the main controller and the sub controller by using data transmission time of a main controller, a time offset, and the propagation delay. A storing unit(204) stores data transmission/reception time of the sub controller, data processing time, and the propagation delay.

Description

Network-based robot control method and its device {APPARATUS AND METHOD FOR ROBOT CONTROL BASED NETWORK}

The present invention relates to a network-based robot control, and more particularly, to a network-based robot control method and apparatus having a main controller and a plurality of auxiliary controllers.

In a network-based robot control system, the data transmitted from the primary controller is received and processed by the secondary controller, respectively, and varies for each secondary controller. That is, each controller has a different delay time until data is received and processed.

Therefore, in a network-based control system including automatic control equipment controllers, time consistency between each controller, such as a primary controller and a secondary controller, must be ensured. When two controllers are scheduled for a certain time at any scheduled time, the action that occurs due to time mismatches degrades the performance of the overall control system.

Therefore, in order to ensure time coherence between the controllers, the controllers of the network-based control system should include a time measurement function of receiving data inside each node.

In addition, even in a network-based control system in which time coherency is guaranteed between controllers, when there is a disconnection of a network cable, propagation delays between controllers may be different from those of controllers in a normal system.

Therefore, even if the time coincidence between the controllers is initially guaranteed, a problem may occur in which time can be inconsistent again due to a network cable error.

An object of the present invention is to propose a method for controlling a network-based control system for automatically maintaining time agreement with respect to the operation of a primary controller and an auxiliary controller when a cable error occurs in a network-based control system.

Another object of the present invention is to propose a network-based control system capable of automatically coping with a network cable error between a primary controller and an auxiliary controller or respective auxiliary controllers.

According to an aspect of the present invention, in a network-based robot control method having a main controller and a plurality of auxiliary controllers, (a) in the main controller to the initial time offset value of the plurality of auxiliary controllers and the initial propagation delay value of the connection lines Extracting, (b) transmitting execution data from the primary controller to the secondary controllers, (c) detecting a failure of any one of the primary controller, the secondary controller or the connection line, and (d) the failure detection result, the connection A control method is provided, comprising changing a network topology upon detecting a line failure and resetting a time offset value of a secondary controller and a propagation delay value of a connection line in correspondence with the changed network topology.

In step (a), (a1) the primary controller transmits initial configuration data, which is arbitrary data for setting an initial time offset value, to the secondary controllers, and (a2) initial propagation delay in the initial configuration data received by the secondary controllers. Extracting and processing a value; (a3) the secondary controllers transmit processed initial configuration data to the primary controller; and (a4) the primary controller uses the processed initial configuration data received from the secondary controllers to offset the initial time offset. Setting a value.

(c) processing (c1) the execution data received by the secondary controllers; (c2) transmitting the processed execution data to the primary controller; and (c3) processing the execution data received by the primary controller. Detecting a failure of the primary controller, the secondary controller or the connection line by using the transmission and reception time and processing time of the execution data of the auxiliary controllers included.

Step (d) is changed to a line topology, a ring topology or a double line topology according to the detected position of the connection line.

When the primary controller transmits data to a plurality of secondary controllers directly connected, the data transmitted to the plurality of secondary controllers are all the same data. Also, when the primary controller receives processed data from a plurality of directly connected secondary controllers, the primary controller acquires one processed data among the processed data. The processed data stores data transmission time and processing time of the auxiliary controllers.

The time offset is the difference between the internal clock value of the primary controller when the primary controller transmits data and the internal clock value of the secondary controller when the secondary controller receives the data. The propagation delay is also the difference between the time the data was sent from the primary controller and the time the data was received from the secondary controller.

According to another aspect of the present invention, a network-based robot control apparatus having a main controller and a plurality of auxiliary controllers, comprising: a transmitter for outputting data to the auxiliary controller, data including data transmission / reception time and processing time of the auxiliary controller; A calculation unit for calculating propagation delays and time offsets of the respective sub-controllers by using the receiving unit, the data transmission / reception time and the processing time of the auxiliary controllers included in the data received by the receiving unit, the propagation delays by the calculation unit, the time offsets, A control including a time matching controller for matching the time of the main controller and the auxiliary controller using the data transmission time of the main controller, and a storage unit storing data transmission / reception time, data processing time, propagation delay, or time offset of the main controller and the auxiliary controller An apparatus is provided.

The primary controller and the secondary controller include two transceivers. Here, the main controller can identify the network topology based on whether data transmission of the transmitter and data reception of the receiver are possible.

The primary controller and the secondary controller include internal clocks that measure the time of transmission and reception of data and the processing time of data.

In addition, the main controller may further include a merge. The primary controller may acquire one piece of data by a merge operation performed in real time when the primary controller receives data from a plurality of secondary controllers directly connected to the primary controller.

Network-based robot control method and apparatus according to the present invention has the advantage that it is possible to prevent the performance degradation of the entire robot control system due to the operation caused by the inconsistency of time in which a specific operation is planned between the controllers.

In addition, there is an advantage in that redundant cabling (Cabling Redundancy) capable of coping with network cable failure.

In addition, even if a network cable error occurs due to a real-time merge operation, it does not affect the logical processing of the system.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description.

Hereinafter, embodiments of a network-based control system according to the present invention will be described in detail with reference to the accompanying drawings. In the following description with reference to the accompanying drawings, the same or corresponding components are given the same reference numerals, and Duplicate explanations will be omitted.

The robot control system consists of a near real time processing system. Therefore, not only the logical processing of the system but also the basis for real-time processing in the network-based control system should be established. For this real-time processing, the primary controller and the secondary controller must share the same time.

For the convenience of understanding and explanation of the present invention, a description will be given assuming that the primary controller is the primary controller and the secondary controller is the secondary controller. However, it will be apparent to those skilled in the art that the primary controller and the secondary controller are not limited to the primary controller and the secondary controller, respectively.

1 is a block diagram showing a network-based robot control system according to an embodiment of the present invention.

According to FIG. 1, the network-based robot control system is largely composed of a main controller 101, an auxiliary controller 102, and a connection line 103.

The primary controller 101 transmits data for controlling the robot to the secondary controller 102. Here, the data transmitted to the auxiliary controller 102 may include a propagation delay value or a time offset value.

Here, the time offset is a difference between the internal clock value of the main controller 101 when the main controller 101 transmits data and the internal clock value of the auxiliary controller 102 when the auxiliary controller 102 receives the data. .

The propagation delay is the delay time until the secondary controller 102 receives the data by transmitting data from the primary controller 101.

The auxiliary controller 102 performs a task for controlling the robot according to the data received from the main controller 101. The auxiliary controller 102 transmits the processing data including the result to the main controller 101 after the job processing for the robot control. The processing data may include a time at which the auxiliary controller transmits and receives data and a data processing time.

The connection line 103 connects the primary controller 101 and the secondary controller 102. The connection line 103 connects the auxiliary controller with another auxiliary controller. It enables data transmission between controllers connected to each other via a connection line 103.

2 is an internal block diagram of the main controller of the network-based robot control system.

Referring to FIG. 2, the main controller 201 includes a time match controller 202, a calculator 203, a storage 204, a merge 205, an internal clock 206, a first transceiver 207, and a first controller. It consists of two transceivers 208. Here, the first transceiver 207 and the second transceiver 208 include a transmitter and a receiver, respectively.

The primary controller 201 transmits data including the propagation delay and time offset to the secondary controller via the first transmitter and the second transmitter. The main controller 201 receives, via the first receiver and the second receiver, processing data including a result of the data transmitted to the secondary controller being processed by the secondary controller.

The main controller 201 can identify the network topology based on whether data transmission of the first and second transmitters and data reception of the first and second receivers are possible.

The main controller 201 may transmit and receive data in both directions through a full duplex method with the auxiliary controller through the first transceiver 207 and the second transceiver 208. In this case, data transmission and reception may be performed through one connection line. Data transmission may be performed by separating the transmission and reception connection lines by two connection lines.

In the embodiment of the present invention, the connection line connected to the first transceiver 207 and the second transceiver 208 is divided into a transmission and a reception connection line.

The time coincidence control unit 202 matches the execution time between the main controller 201 and the secondary controller. That is, when the main controller 201 transmits data to the secondary controller for robot control by the time matching controller 202, the secondary controller performs control operation at the desired time by the primary controller 201 based on the received data. Can be done.

The calculation unit 203 calculates a propagation delay value and a time offset value of the auxiliary controller using the data transmission / reception time and the processing time of the auxiliary controller included in the processing data received by the first receiver and the second receiver. In the case where there are a plurality of auxiliary controllers, the transmission / reception time and processing time of each of the auxiliary controllers for which data is processed are included in the processed data. Therefore, when there are a plurality of auxiliary controllers, the calculator 203 may calculate a propagation delay value and a time offset value for each auxiliary controller.

The storage unit 204 stores data transmission / reception time, data processing time, propagation delay value and time offset value of the primary controller 201 and the secondary controller.

When the merge 205 simultaneously receives data to the first receiver and the second receiver of the main controller 201, the merge 205 selects only one data from the simultaneously received data. The data selection operation of the merge 205 is performed in real time. Even if a connection line failure is caused by the merge 205 operation performed in real time, logical processing of the system is not affected.

The internal clock 206 may measure data transmission / reception time and data processing time of the main controller 201. By including the internal clock 206 in the main controller 201, the time of the internal clock 206 of the main controller 201 is set as the reference time, unlike the conventional time based on the time of the internal clock of the secondary controller.

3 is an internal block diagram of an auxiliary controller of a network-based robot control system.

According to FIG. 3, the auxiliary controller 301 includes a time matching controller 302, an internal clock 303, a first transceiver 304, and a second transceiver.

The first transceiver 304 and the second transceiver 305 include a transmitter and a receiver, respectively. The first transmitter and the second transmitter transmit data from the secondary controller 301 to the primary controller or another secondary controller 301. The first receiver and the second receiver receive data from the primary controller or another secondary controller 301.

The time coincidence control unit 302 matches the execution time of the work between the main controller and the auxiliary controller 301. When the auxiliary controller 301 receives data for controlling the robot from the main controller, the time controller 302 of the auxiliary controller 301 may set a desired control execution time by the main controller. That is, the auxiliary controller 301 performs the control operation at the time desired by the main controller by the time matching controller 302.

The internal clock 303 may measure data transmission / reception time and data processing time of the auxiliary controller 301. The data transmission / reception time and data processing time measured by the internal clock 303 of the auxiliary controller 301 are used to calculate the data propagation delay value and time offset value between the main controller and the auxiliary controller 301.

4 is a flowchart illustrating a network-based robot control method according to an embodiment of the present invention.

Referring to FIG. 4, first, initial time offset values of a plurality of auxiliary controllers and initial propagation delay values of connection lines are extracted from a primary controller (S401). The initial propagation delay value can be extracted by using the time taken for the initial data to be transmitted to the secondary controller to extract the initial propagation delay value when the system including the primary controller boots.

Subsequently, execution data is transmitted from the primary controller to the secondary controllers (S402). At this time, the execution data of the primary controller is connected to the first secondary controller and the fourth secondary controller. The first auxiliary controller is connected with the second auxiliary controller, and the second auxiliary controller is connected with the third auxiliary controller. And since the third auxiliary controller is connected to the fourth auxiliary controller, the main controller and the first to fourth auxiliary controllers are connected in a ring form. In addition, the main controller and the first auxiliary controller to the fourth auxiliary controller are provided with a first transceiver and a second transceiver, respectively, and are connected by a double line.

When the execution data is transmitted from the primary controller to the secondary controllers, the execution data is simultaneously transmitted to the first secondary controller and the fourth secondary controller. That is, when the main controller transmits data to a plurality of directly connected secondary controllers, the data transmitted to the connected plurality of secondary controllers are all the same data. Execution data sent to the first secondary controller is transmitted and processed to the secondary controller in low order. At the same time, the execution data transmitted to the fourth secondary controller is transmitted and processed to the secondary controller in high order.

The data processed by each secondary controller is finally received by the primary controller.

Subsequently, the main controller detects a failure of any one of the main controller, the auxiliary controller, or the connection line (S403). The fault location is extracted from the execution data transmission time and movement path of each auxiliary controller included in the final processing data received from the primary controller.

Subsequently, as a result of detecting the failure, the network topology is changed when the connection line failure is detected (S404). For example, if a failure of a connection line connecting the second secondary controller and the third secondary controller is detected, the network topology will be changed to a two line topology. That is, the primary controller and the first secondary controller are connected, and the first secondary controller and the second secondary controller are connected to form a first line topology. In addition, a main controller and a fourth auxiliary controller are connected, and a fourth auxiliary controller and a third auxiliary controller are connected to form a second line topology.

Subsequently, in accordance with the changed network topology, the time offset value of the auxiliary controller and the propagation delay value of the connection line are reset (S405). That is, the propagation delay value and the time offset value corresponding to each of the first line topology and the second line topology are calculated and reset.

5 is a flowchart illustrating a method of extracting an initial time offset value and an initial propagation delay value according to an embodiment of the present invention.

Referring to FIG. 5, first, the main controller transmits initial setting data, which is arbitrary data for setting an initial time offset value, to the auxiliary controllers (S501). In this case, when the main controller transmits the initial configuration data, it may be a time point at which the system including the main controller is booted or an arbitrary set time. In addition, the secondary controller to which the primary controller transmits the initial configuration data is the secondary controller directly networked with the primary controller.

Subsequently, the auxiliary controller processes the initial setting data received (S502). That is, the secondary controller performs operations on the initial configuration data received from the primary controller.

Subsequently, the secondary controller transmits the processed initial setting data to the primary controller (S503). If there are a plurality of auxiliary controllers, the initial setting data is transmitted to the main controller after finishing processing through the plurality of auxiliary controllers. For example, when the primary controller and the first secondary controller to the fourth secondary controller are connected in a ring topology, the primary controller transmits initial configuration data to the first secondary controller and the second secondary controller. Thereafter, the initial configuration data is transmitted and received and processed from the first auxiliary controller and the fourth auxiliary controller to the connected secondary controller in turn, and finally the processed initial configuration data is transmitted to the primary controller.

Subsequently, the primary controller sets an initial propagation delay value and a time offset value by using the processed initial setting data received from the secondary controller (S504). The processed initial setting data includes time and processing time transmitted and received to each secondary controller. That is, the initial configuration data received by the primary controller includes initial configuration data transmission / reception time and processing time of the secondary controller included in the movement path of the initial configuration data. Therefore, the initial time offset value is calculated and set using the initial setting data transmission / reception time and processing time of the primary controller and each secondary controller.

6 is a flowchart illustrating a method for detecting a connection failure according to an embodiment of the present invention.

According to FIG. 6, first, execution data received by the auxiliary controllers is processed (S601).

Subsequently, the processed execution data is transmitted to the main controller (S602).

Subsequently, a failure of the main controller, the auxiliary controller, or the connection line is detected using the transmission and reception time and the processing time of the execution data of the auxiliary controllers included in the processed execution data received by the main controller (S603).

In order to more easily understand the embodiment of the present invention, an example will be described as follows.

The main controller and the first to fourth auxiliary controllers are connected in a ring topology, and there is a failure in the connection line connecting the second and third auxiliary controllers.

 The primary controller simultaneously transmits the execution data to the first secondary controller and the fourth secondary controller. Here, the first auxiliary controller and the fourth auxiliary controller are directly networked with the main controller.

The first secondary controller and the fourth secondary controller process execution data received from the primary controller. Subsequently, the first-first processing data, which is the execution data processed by the first auxiliary controller, is transmitted to the second auxiliary controller. Also, the 2-1th processing data, which is the execution data processed by the fourth auxiliary controller, is transmitted to the third auxiliary controller. In the first-first process data, the result of the execution data processed by the first auxiliary controller is updated with the execution data received from the main controller. In addition, in the 2-1 process data, the result of the execution data processed by the fourth auxiliary controller is updated with the execution data received from the main controller. In this case, the updated processing result may include a time at which the first auxiliary controller and the second auxiliary controller receive the execution data, a time of processing the execution data, a time of transmitting the 1-1 process data and the 2-2 process data, and the like. It includes.

The second auxiliary controller then processes the received 1-1 process data. In addition, the third auxiliary controller processes the received 2-1 processing data.

In this case, the second auxiliary controller and the third auxiliary controller are not connected to each other due to a failure. Therefore, the 1-2 processing data, which is the data processed by the second auxiliary controller, and the 2-2 processing data, which is the data processed by the third auxiliary controller, cannot be transmitted to the third auxiliary controller and the second auxiliary controller, respectively. Therefore, the 1-2 processing data and the 2-2 processing data become final data.

Subsequently, the 1-2 processing data is transmitted to the primary controller via the first secondary controller. In addition, the second-2 process data is also transmitted to the primary transmission controller via the fourth auxiliary controller.

Subsequently, the main controller extracts a location where a connection failure occurs by using the data transmission / reception time and processing time and initial setting data transmission / reception time and processing time included in the received final data.

7 is an exemplary diagram illustrating a change in network topology due to a failure of a connection line according to an embodiment of the present invention.

7A is a ring topology as an initial network topology.

At this time, the network topology is changed to a line topology or a double line topology, depending on the position of the connection line that has failed in the ring topology.

FIG. 7B illustrates a case where a failure occurs in the fifth connection line 703, which is a connection line connecting the main controller 701 and the fourth auxiliary controller 702. As a result of the failure of the fifth connection line 703, it can be seen that the ring topology has been changed to a line topology.

FIG. 7C illustrates a case where a failure occurs in the third connection line 706, which is a connection line connecting the third auxiliary controller 704 and the fourth auxiliary controller 705. As a result of the failure of the third connection line 706, it can be confirmed that the ring topology has been changed to the double line topology.

8 is an exemplary diagram illustrating a data transmission / reception path according to a network topology according to an embodiment of the present invention.

As can be seen in Figure 8, the sequential address of the secondary controller can be determined by the physical network connection according to the type of network topology.

8A illustrates a data transmission / reception path of a ring topology when a failure of a connection line does not occur.

FIG. 8B illustrates a data transmission / reception path when a failure occurs in the fifth connection line 803 connecting the main controller 801 and the fourth auxiliary controller 802 in FIG. 8A.

Loop back internally in case of a failure in the connection line connected to the primary or secondary controller. That is, when the fourth auxiliary controller 802 detects a failure of the fifth connection line 803, the fourth auxiliary controller loops back data and transmits the data to the third auxiliary controller 805.

That is, due to the failure of the fifth connection line 803, data is transmitted through the data transmission and reception path as in the case of the ring topology.

FIG. 8C illustrates a data transmission / reception path when a failure occurs in the third connection line 806 connecting the second auxiliary controller 804 and the third auxiliary controller 805 in FIG. 8A.

At this time, the data transmitted from the main controller 801 to the second auxiliary controller 804 detects a failure of the third connection line 806 connected to the second auxiliary controller, and loops back the data inside the second auxiliary controller. Send to first auxiliary controller 807.

In addition, the data transmitted from the main controller 801 to the third auxiliary controller 805 detects a failure of the third connection line 806 connected to the third auxiliary controller 805, and internally stores the data in the third auxiliary controller. Loop back and transmit to the fourth auxiliary controller 802.

That is, due to the failure of the third connection line 806, data is transmitted through a data transmission / reception path such as a double line topology.

As described above, it can be seen from FIG. 8A to FIG. 8C that the movement path of data is changed by changing the network topology depending on the location of the failed connection line. That is, due to the change of the movement path of the data, the propagation delay value until each secondary controller receives the data transmitted by the primary controller may be different from the initial propagation delay value. For example, in FIG. 8A to FIG. 8C, the value of T_3_0 of the third auxiliary controller may be measured as another value. Here, T_3_0 is a time when data is transmitted from the third auxiliary controller. In the case of FIGS. 8A and 8B, the value of T_3_0 includes data transmission / reception time and data processing time in the first and second auxiliary controllers. However, in the case of FIG. 8C, the value of T_3_0 includes data transmission and reception time of the fourth auxiliary controller and data transmission and processing time of the third auxiliary controller.

9 is an exemplary view showing definitions of variables for calculating a propagation delay value and a time offset value according to an embodiment of the present invention.

The time offset is the difference between the internal clock value of the primary controller when transmitting data from the primary controller and the internal clock value of the secondary controller when the secondary controller receives data.

The propagation delay is the difference between the time the data is sent from the primary controller and the time the data is received from the secondary controller. That is, a propagation delay may occur due to data transmission between the primary controller and the secondary controller or the secondary controllers. In addition, a propagation delay may occur in data processing in the main controller or auxiliary controller and internally transferring data to the transceiver.

By this propagation delay, time offset values are set and control is performed at the time of performing control of the main controller or the auxiliary controller, respectively.

However, the propagation delay value may change due to the change of the data transmission path due to the network topology changed by the fault location of the connection line. Therefore, in such a case, it is necessary to reset the time offset value again.

FIG. 10 is an exemplary diagram illustrating a propagation delay value when data is transmitted by connecting a primary controller and a secondary controller in a forward direction according to another embodiment of the present invention.

T_PDF_l represents the propagation delay value of the secondary controller at sequential address l when data is transmitted in the forward direction. L [n] is the time taken for data to move to the nth connection line. T_Pro is the time it takes for the data to be processed in the primary or secondary controller. T_For is the time taken for data to travel from the receiver to the transmitter internally in the primary or secondary controller.

When the primary controller and the secondary controller are connected in the forward direction, T_PDF_l is calculated as shown in [Equation 1].

[Equation 1]

T_PDF_1 = L [1]

T_PDF_2 = L [1] + L [2] + T_Pro

T_PDF_3 = L [1] + L [2] + L [3] + 2 * T_Pro

In addition, the time taken by the primary controller or the secondary controller to receive again after processing the data transmitted in the forward direction can be calculated as shown in Equation 2 below.

[Equation 2]

t [1] = T_0_0-T_R

t [2] = T_1_0-T_1_1

t [3] = T_2_0-T_2_1

Here, t [n] represents the time taken by the primary controller or the secondary controller to receive data again after processing. Where n is # l + 1. For example, t [1] is the time it takes for the data sent to the primary controller to be processed through the secondary controllers before the processed data is received back to the primary controller. t [2] is a time taken until the first auxiliary controller receives the processed data again after the data transmitted from the first auxiliary controller is processed through the other auxiliary controllers.

Here, the data transmission and processing time between the primary controller and the first secondary controller or secondary controllers can be expressed as shown in [Equation 3].

&Quot; (3) "

L [1] = (t [1] -t [2] -T_For) / 2

L [2] + T_Pro = (t [2] -t [3] + T_Pro-T_For) / 2

L [3] + T_Pro = (t [3] -T_For) / 2

L [3] + T_For = (t [3] -T_For + 2 * T_Pro) / 2

L [2] + T_For = (t [2] -t [3] -T_Pro + T_For) / 2

L [1] + T_For = (t [1] -t [2] + T_For) / 2

11 is an exemplary diagram illustrating a propagation delay value when data is transmitted by connecting a main controller and a secondary controller in a reverse direction according to another embodiment of the present invention.

T_PDR_l represents the propagation delay value of the secondary controller at sequential address l when data is transmitted in the reverse direction.

When the primary controller and the secondary controller are connected in the reverse direction, T_PDR_l is calculated as shown in [Equation 4].

&Quot; (4) "

T_PDR_1 = L [3] + L [2] + T_For + L [1] + T_For

T_PDR_2 = L [3] + L [2] + T_For + L [1] + T_For + L [1] + T_Pro

T_PDR_3 = L [3] + L [2] + T_For + L [1] + T_For + L [1] + T_Pro + L [2] + T_Pro

In addition, the time taken until the primary controller or the secondary controller receives the data transmitted in the reverse direction again after processing can be calculated as shown in Equation 5 below.

[Equation 5]

t [0] = T_0_1-T_R

t [1] = T_3_1-T_3_0

t [2] = T_2_1

12 is an exemplary diagram illustrating a method of resetting a propagation delay value and a time offset value due to a failure of a connection line according to an embodiment of the present invention.

According to FIG. 12, the ring topology is changed to a double line topology due to a failure of the connection line. That is, it can be confirmed that the transmission path of data is changed by the failure of the connection line between the third and fourth auxiliary controllers. The propagation delay value and the time offset value of the third auxiliary controller and the fourth auxiliary controller according to the change of the data transmission path are reset.

The propagation delay value T_SL [n] in the initial ring topology is expressed by Equation 6 below.

&Quot; (6) "

T_SL [3] = L [1] + L [2] + T_Pro + L [3] + T_Pro

T_SL [4] = L [1] + L [2] + T_Pro + L [3] + T_Pro + L [4] + T_Pro

The propagation delay value T_DL [n] after changing to the double line topology due to the failure of the connection line is expressed by Equation 7 below.

[Equation 7]

T_SL [3] = L [0] + L [4] + T_For + T_For

T_SL [4] = L [0] + L [4] + T_For + T_For + L [4] + T_Pro

In this manner, the time offset value T_OFF can be recalculated using Equation 8 using the initial propagation delay value and the propagation delay value after the topology change.

[Equation 8]

T_OFF_3 = Old Value- (T_SL [3] -T_DL [3])

T_OFF_4 = Existing Value- (T_SL [4] -T_DL [4])

Here, the existing value is the time offset value of each of the third and fourth auxiliary controllers in the initial ring topology.

As such, when a failure of the connection line is detected, the time offset value corresponding to the change of the changed topology may be reset by a simple equation by using the initial propagation delay and the initial offset value.

In the embodiment of the present invention, when a failure of a connection line occurs on the basis of a ring topology, it may be explained that a line topology or a double line topology may be changed according to the position of the connection line where the failure occurs. However, the changeable topology is not limited to this, and can be changed and expanded to various network topologies according to the type of initial topology and the location of the failed connection line.

Network-based robot control method and apparatus according to the present invention has the advantage that it is possible to prevent the performance degradation of the entire control system due to the operation caused by the inconsistency of the time that the specific operation is planned between the controller.

In addition, there is an advantage in that redundant cabling (Cabling Redundancy) capable of coping with network cable failure.

In addition, even if a network cable error occurs due to a real-time merge operation, it does not affect the logical processing of the system.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art to which the present invention pertains without departing from the spirit and scope of the present invention as set forth in the claims below It will be appreciated that modifications and variations can be made.

1 is a block diagram showing a network-based robot control system according to an embodiment of the present invention.

2 is an internal block diagram of a main controller of a network-based robot control system.

3 is an internal block diagram of an auxiliary controller of a network-based robot control system.

4 is a flow chart showing a network-based robot control method according to an embodiment of the present invention.

5 is a flowchart illustrating a method of extracting an initial time offset value and an initial propagation delay value according to an embodiment of the present invention.

6 is a flowchart illustrating a method for detecting a connection failure according to an embodiment of the present invention.

7 is an exemplary view illustrating a change in network topology due to a failure of a connection line according to an embodiment of the present invention.

8 is an exemplary view showing a data transmission and reception path according to a network topology according to an embodiment of the present invention.

9 is an exemplary view showing definitions of variables for calculating a propagation delay value and a time offset value according to an embodiment of the present invention.

10 is an exemplary diagram illustrating a propagation delay value when data is transmitted by connecting a primary controller and a secondary controller in a forward direction according to another embodiment of the present invention.

11 is an exemplary diagram illustrating a propagation delay value when data is transmitted by connecting a primary controller and a secondary controller in a reverse direction according to another embodiment of the present invention.

12 is an exemplary view illustrating a method of resetting a propagation delay value and a time offset value due to a failure of a connection line according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

101 201: main controller

102 301: Auxiliary Controller

103: connection line

202 302: time matching controller

203: calculation unit

204: storage unit

205: Merge

206 303: Internal Clock

207 304: first transceiver

208 305: second transceiver

Claims (17)

In the network-based robot control method comprising a main controller and a plurality of auxiliary controllers, (a) extracting initial time offset values of the plurality of auxiliary controllers and initial propagation delay values of the connection lines in the primary controller; (b) sending execution data to the secondary controllers at the primary controller; (c) detecting a failure of either the primary controller, the secondary controller or the connection line; (d) changing a network topology upon detecting the connection line failure as a result of the failure detection; And and (e) resetting a time offset value of the auxiliary controller and a propagation delay value of the connection line according to the changed network topology. The method of claim 1, In step (a), (a1) the primary controller transmitting initial configuration data to the secondary controllers which is any data for setting the initial time offset value; (a2) processing the initial configuration data received by the auxiliary controllers; (a3) the secondary controllers transmitting the processed initial configuration data to the primary controller; And (a4) the main controller comprising setting the initial propagation delay value and the time offset value using the processed initial setting data received from the auxiliary controllers. The method of claim 1, Step (c) is, (c1) processing the execution data received by the auxiliary controllers; (c2) sending the processed execution data to the main controller; And (c3) detecting a failure of the main controller, the auxiliary controller or the connection line by using the transmission / reception time and the processing time of the execution data of the auxiliary controllers included in the processed execution data received by the main controller. Robot control method comprising a. The method of claim 1, In step (d), And a line topology, a ring topology, or a double line topology according to the detected fault position of the connection line. The method of claim 1, And when the main controller transmits data to a plurality of directly connected secondary controllers, the data to be transmitted to the plurality of secondary controllers are all the same data. The method of claim 5, And when the main controller receives processed data from a plurality of directly connected secondary controllers, the main controller acquires one processed data among the processed data. The method of claim 3, wherein The processed data is a robot control method characterized in that the data transmission time and processing time of the auxiliary controllers are stored. The method of claim 1, The time offset is a difference between an internal clock value of the main controller when the main controller transmits data and an internal clock value of the auxiliary controller when the auxiliary controller receives the data. Robot control method. The method of claim 1, The propagation delay is a robot control method, characterized in that the difference between the time the data is transmitted from the primary controller and the time the data is received from the secondary controller. In the network-based robot control device having a main controller and a plurality of auxiliary controllers, A transmitter for transmitting data to the auxiliary controller; A receiver configured to receive data including a data transmission / reception time and a data processing time of the auxiliary controller; A calculator configured to calculate a propagation delay and a time offset of each auxiliary controller using data transmission / reception time and processing time of the auxiliary controller included in the data received by the receiver; A time coincidence control unit which matches the time of the main controller and the auxiliary controller using the propagation delay, the time offset, and the data transmission time of the main controller by the calculation unit; And And a storage unit for storing data transmission / reception time, data processing time, propagation delay, or time offset of the main controller and the auxiliary controller. The method of claim 10, The main controller and the auxiliary controller is configured to include two transceivers. The method of claim 10, The main controller identifies a network topology based on whether data transmission of the transmitter and data reception of the receiver are possible. The method of claim 10, The main controller and the auxiliary controller includes an internal clock for measuring the transmission and reception time of the data and the processing time of the data. The method of claim 10, And the time offset is a difference between an internal clock value of the main controller when the main controller transmits data and an internal clock value of the auxiliary controller when the auxiliary controller receives the data. The method of claim 10, The propagation delay is a robot control apparatus, characterized in that the difference between the time the data is transmitted from the primary controller and the time the data is received from the secondary controller. The method of claim 10, The main controller further comprises a merge (Merge). The method of claim 13, And when the main controller receives data from the plurality of auxiliary controllers directly connected to the main controller, acquires one data by the merge operation performed in real time.

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