KR20070032495A - Data transmission method for remote control of robot - Google Patents

Abstract

According to the present invention, when controlling a remote robot via the Internet, the robot control data is transmitted in a wired section using UDP and the robot control data is transmitted in a wireless section using a multi-transmission technique, thereby speeding up the transmission of the robot control data. And to improve reliability.

To this end, the present invention provides a data transmission method for remotely controlling a robot via the Internet, comprising: a first step of generating a UDP packet corresponding to the command when a predetermined command is input from the robot remote controller; A second step of preferentially transmitting the UDP packet in a router; And when the UDP packet is transmitted to the base station managing the robot, the base station multi-transmits the UDP packet to the robot.

Description

DATA TRANSMISSION METHOD FOR REMOTE CONTROL OF ROBOT}

1 is an overall network configuration to which a data transmission method for remote control of a robot according to an embodiment of the present invention is applied.

2 and 3 are flowcharts for explaining a data transmission method for remote control of a robot according to an embodiment of the present invention.

The present invention relates to a data transmission system and method for remote control of a robot, and more particularly, reliability of data (hereinafter, robot control data) transmitted for controlling a robot at a remote location through a wired internet and a wireless internet. It's about a technology that guarantees.

With the concept of the World Wide Web, an Internet network that can be easily accessed from anywhere in the world has become commonplace. In the mid-'90s, the field of Internet robotics, which remotely controls mobile robots by combining the Internet and mobile robots, is actively being researched and developed. . As an example of a remote control system of a mobile robot using such an internet network, an object hidden in sand by using an air nozzle and a vision system to see a picture transmitted through the Internet and control a robot's arm to stack blocks It is being moved in many fields, such as remote gardening system for finding a remote control system, a system for controlling a sensor-based mobile robot through the Internet, and a remote exhibition system on the Internet.

The remote control systems of the mobile robot using the Internet are not directly controlled by the operator, but by setting only the final target of the robot's movement, the rest of the control is a system that the mobile robot can do on its own. Such a control system of a mobile robot is called a supervisory control system, and is published in the publication [Proc. IEEE Int. Symposium on Industrial Electronics, Vol. 1, pp. ss60-ss64] to T.M. Published by Chen as Remote Supervisory control of An Autonomous Mobile Robot Via World Wide Web.

According to the disclosed technique, when the operator sends a command for the final target point of the mobile robot, a supervisory control method of the mobile robot through the Internet is performed, which is performed while the mobile robot controls the movement by itself.

Meanwhile, when transmitting a command (hereinafter, referred to as robot control data) for controlling a mobile robot through the Internet, TCP (Transmission Control Protocol) or UDP (User Datagram Protocol) is used.

TCP divides the data into packets, checks the packet transmission status, and then transmits the next packet. Therefore, TCP has a problem in that data transmission is reliable while time delay is involved. Particularly, since TCP is known to show a much larger packet loss than a wire when the wireless communication medium is included, when the robot is to be controlled through the wireless Internet, the packet loss is increased due to the packet loss. The problem may arise that the delay is increased. This has the problem that rapid robot control cannot be achieved.

Although the use of UDP may be considered to solve the above problems, UDP does not go through a check process for data transmission, and there is a problem in that reliability cannot be guaranteed in data transmission because there is no countermeasure for an error. In particular, since UDP has a high packet loss rate in a wireless communication medium, data reliability may be more problematic when trying to control a robot wirelessly.

The present invention has been made in view of the above circumstances, and an object of the present invention is to transmit robot control data using UDP in a wired section and to use a multi-transmission technique in a wireless section when controlling a remote robot via the Internet. By transmitting the robot control data, it is possible to improve the speed and reliability in the transmission of the robot control data.

In order to achieve the above object, the data transmission method for remote control of the robot according to the present invention, in the data transmission method for remote control of the robot via the Internet, when a predetermined command is input from the robot remote controller, Generating a UDP packet corresponding to the command; A second step of preferentially transmitting the UDP packet in a router; And when the UDP packet is transmitted to the base station managing the robot, the base station multi-transmits the UDP packet to the robot.

Preferably, in the first step of the present invention, the UDP packet is characterized in that the PRI value is stored in the priority field, and the IP address of the robot is recorded in the destination IP address.

Preferably, in the present invention, the second process may include: a 2-1 process of confirming whether the UDP packet is using the header information of the IP packet received from the router; A step 2-2 of checking the priority field of the UDP packet if the IP packet is the UDP packet and checking whether the PRI value is greater than or equal to a threshold value; If the PRI value is greater than or equal to the threshold, transmitting the UDP packet on a priority basis; And if the IP packet is not the UDP packet or the PRI value is less than the threshold value, transmitting the IP packet according to a FIFO mechanism.

And preferably, the third step in the present invention, step 3-1 to determine whether the UDP packet using the header information of the IP packet received at the base station; Step 3-2, if the IP packet is the UDP packet, checking whether the PRI value is greater than or equal to a threshold by querying a priority field of the UDP packet; And if the PRI value is greater than or equal to the threshold value, a third process of multiplying the UDP packet to the robot corresponding to the destination IP address.

Also, in the present invention, step 3-3 may include: step 3-3-1 of storing the UDP packet in a buffer; 3-3-2 process of transmitting the UDP packet to the robot by loading the UDP packet; 3-3-3, transmitting the UDP packet to the robot until the number of transmissions reaches a predetermined number of times; And 3-3-4 deleting the UDP packet from the buffer when the number of transmissions reaches the predetermined number of times.

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

1 is an overall network configuration to which a data transmission method for remote control of a robot according to an embodiment of the present invention is applied.

In FIG. 1, the robot 50 to be controlled is given a unique IP address, receives robot control data based on wireless communication, and operates based on the robot control data. Although not shown in the drawing, the robot 50 includes an interface means for supporting wireless communication, a main processor for analyzing and controlling the robot control data received on the basis of wireless communication, and control of the main processor. Preferably, a plurality of means operating underneath are provided.

The robot 50 operates under the control of the remote user terminal 10, and the user terminal 10 transmits robot control data for remotely controlling the robot 50 through the internet 20 and the base station 40. By transmitting to 50, the robot 50 can be remotely controlled.

Preferably, the user terminal 10 includes an application for robot control, and performs a function of transmitting the robot control data into UDP packets by the robot control application to the Internet 20. The robot control data is preferably composed of IP packets based on the UDP specification, and it is preferable to set the priority field (PRI) of the IP packet to a maximum value of 15. This is made possible by being based on IPv6.

As is known, the Internet 20 includes a plurality of routers, and performs a function of delivering IP packets to a destination by a routing operation between routers. In FIG. 1, only edge routers provided in the Internet are illustrated as routers 22 and 24.

When the IP packet is transmitted, the router 22 checks whether the IP packet is a UDP packet based on the header information of the IP packet. If the IP packet is identified as a UDP packet, the router 22 preferentially transmits the UDP packet to control the robot. Ensure the speed of your data.

  When the UDP packet is transmitted from the router 24, the base station 40 performs the function of loading the UDP packet on the RF signal and transmitting the UDP packet to the target terminal. In particular, if the PRI value of the priority field of the UDP packet is set to "15", the base station 40 recognizes the UDP packet as the robot control data, stores it in the built-in buffer, and retransmits the robot control data by a predetermined number of times. Ensure the reliability of

Next, with reference to the flowchart shown in Figures 2 to 3, the operation of the data transmission method for remote control of the robot according to an embodiment of the present invention will be described in detail.

When the robot remote controller inputs a command for controlling a specific robot using the robot control application provided in the user terminal 10, the user terminal 10 generates a UDP packet corresponding to the robot control command and generates the Internet packet. 20). At this time, the PRI value of the priority field of the UDP packet is set to "15", and it is preferable that the destination IP address is the IP address of the robot 50.

The UDP packet is transmitted to the router 22 of the Internet 20 through an internet access network (not shown), so that the router 22 can receive the UDP packet.

The router 22 determines whether the received IP packet is a UDP packet (S12), and if it is determined as a UDP packet (YES in S12), the router 22 checks whether the PRI value of the priority field is "15" which is the highest value (S14). . In step S12, the router determines whether the IP packet is a UDP packet based on the header information of the IP packet.

As a result of the determination in step S14, if the PRI value is determined to be "15", the router preferentially transmits the corresponding UDP packet, so that the UDP packet is quickly transmitted.

However, if the determination result in step S12 is not confirmed that the IP packet is a UDP packet (No in S12), or the determination result in step S14 is that the PRI value of the priority of the UDP packet is not "15", The data is stored in a queue and transmitted to the FIFO queuing mechanism (S18).

Meanwhile, when the UDP packet routed through the above-described process is transmitted from the router 24 to the base station 40 by the destination IP address, and the base station 40 receives the packet (S20), the base station 40 receives the packet. It is checked whether the IP packet is a UDP packet (S22).

The base station 40 also checks whether the IP packet is a UDP packet based on the header information of the IP packet, and if the IP packet is identified as a UDP packet (Yes in S22), the PRI value of the priority field of the UDP packet. It is checked whether or not this maximum value is "15" (S24).

As a result of the determination in step S24, if the PRI value of the priority field of the UDP packet is "15", the base station 40 stores the UDP packet in an embedded buffer (not shown) (S26), and stores the UDP packet in RF. The signal is transmitted to the robot 50 corresponding to the destination IP address (S28). At this time, the UDP packet transmitted to the robot 50 is robot control data.

Subsequently, the base station 40 performs the multi-transmission of the UDP packet, and when the multi-transmission is completed (S30), deletes the UDP packet from the buffer (S32), and ends the series of operations.

Here, the multi-transmission of the UDP packet may be performed by repeatedly transmitting the UDP packet based on the signal transmission period in a state in which a signal transmission period is determined in consideration of the distance between the base station 40 and the robot 50. Can be.

In another embodiment, after the UDP packet is transmitted, the UDP packet is repeatedly transmitted until the ACK signal is received from the robot 50 by receiving an ACK signal from the robot 50. Multiple transmissions on packets can also be performed.

On the other hand, if it is determined in S22 that the IP packet received by the base station 40 is not a UDP packet (No in S22), or the PRI value of the UDP packet does not correspond to "15" (No in S24), The base station 40 transmits the UDP packet to a destination IP address (S34), and ends a series of processes.

As described above, according to the data transmission method for remote control of a robot according to an embodiment of the present invention, when controlling a remote robot via the Internet, the robot by transmitting the robot control data using UDP in a wired section by the robot The control data is quickly transmitted, and in the section, the robot control data is transmitted by using the multi-transmission technique, thereby ensuring the reliability of the robot control data transmission.

On the other hand, the present invention is not limited to the above-described embodiment, but can be modified and modified within the scope not departing from the gist of the present invention, such modifications and changes should be regarded as belonging to the following claims. will be.

Claims (9)

In the data transmission method for remotely controlling the robot through the Internet, The robot control data corresponding to the command input from the robot remote controller is transmitted as a UDP packet in a wired section, and in the wireless section, data transmission for remote control of the robot is transmitted by copying the UDP packet and transmitting it to the robot. Way. In the data transmission method for remotely controlling the robot through the Internet, Generating a UDP packet corresponding to the command when a predetermined command is input from the robot remote controller; A second step of preferentially transmitting the UDP packet in a router; And When the UDP packet is transmitted to the base station for managing the robot, the base station has a third step of multi-transmitting the UDP packet to the robot. The robot of claim 1 or 2, wherein the robot The data transmission method for remote control of the robot, characterized in that the operation by receiving the UDP packet by wireless communication. The method according to claim 1 or 2, PRI value is set to the highest value in the priority field of the UDP packet, the UDP packet is transmitted in the Internet preferentially data transmission method for the robot. The method of claim 2, wherein the UDP packet in the first process PRI value is stored in the priority field, the data transmission method for the remote control of the robot, characterized in that the IP address of the robot is recorded in the destination IP address. The method of claim 5, wherein the second process Step 2-1 of checking whether the UDP packet is received by using header information of the IP packet received by the router; A step 2-2 of checking the priority field of the UDP packet if the IP packet is the UDP packet and checking whether the PRI value is greater than or equal to a threshold value; If the PRI value is greater than or equal to the threshold, transmitting the UDP packet on a priority basis; And And if the IP packet is not the UDP packet or the PRI value is less than the threshold value, a 2-4 process of transmitting the IP packet according to a FIFO mechanism. . The method of claim 5, wherein the third process is Step 3-1 of checking whether the UDP packet is received by using header information of the IP packet received by the base station; Step 3-2, if the IP packet is the UDP packet, checking whether the PRI value is greater than or equal to a threshold by querying a priority field of the UDP packet; And if the PRI value is greater than or equal to the threshold value, a third to third processes of transmitting the UDP packet to the robot corresponding to the destination IP address. The method of claim 7, wherein the third-3 process is A third-3-1 process of storing the UDP packet in a buffer; 3-3-2 process of transmitting the UDP packet to the robot by loading the UDP packet; 3-3-3, transmitting the UDP packet to the robot until the number of transmissions reaches a predetermined number of times; And And when the number of times of transmission reaches the predetermined number of times, a 3-3-4 process of deleting the UDP packet from the buffer. The method of claim 8, wherein the transmission period of the UDP packet is The data transmission method for remote control of the robot, characterized in that the setting based on the distance to the robot.

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