KR20240107524A - following robot following mobile terminal - Google Patents

Abstract

A tracking control technology for a robot that identifies and follows a person is disclosed.
The RF signal transmitted by the short-range communication module of the mobile communication terminal owned by the master is received through a multi-antenna array, and the angle of arrival is used to determine the driving direction for follow-up driving. Additionally, location information of the mobile communication terminal possessed by the master can be received from data received through the same short-range wireless communication unit and used to calculate the driving direction.

Description

A following robot that follows a mobile communication terminal {following robot following mobile terminal}

A tracking control technology for robots, particularly robots that identify and follow people, is disclosed.

A follower robot that identifies and tracks a master and follows it is known. Follower robots are being applied to carts that carry loads at farms and industrial sites, as well as golf carts. Publication Patent No. 2020-0087361, published on July 21, 2020, creates a bounding box surrounding the master from an image captured by a camera, obtains the center point of the bounding box, and changes the image as the master moves. The master's position is tracked based on the position of the center point of the moving bounding box within it. If the master is re-detected while traveling in the predicted direction, the robot continues position tracking and follow-up driving.

In addition, Registered Patent No. 1,303,911, registered on August 29, 2013, receives a ZigBee communication type wireless tracking signal output from an object terminal mounted on the master, calculates the distance to the master from the intensity information, and calculates the distance to the master from the strength information included in the wireless tracking signal. A technology for controlling the tracking drive unit by determining the direction of movement of the object terminal worn by the master from the geomagnetic sensor information of the object terminal and the geomagnetic sensor information of the follower robot is disclosed. However, not only is it not easy to calculate the absolute distance based on intensity information, but direction is more important than distance in tracking driving, and since it relies only on the geomagnetic sensor, there are limitations to tracking driving.

The purpose of the proposed invention is to introduce position tracking technology that can be easily implemented at a short distance into a tracking robot.

Furthermore, the proposed invention aims to improve the reliability of the tracking robot by combining widely known positioning technologies.

Furthermore, another purpose of the proposed invention is to increase the usability of the follower robot.

According to one aspect of the proposed invention, the RF signal transmitted by the short-range communication module of the mobile communication terminal possessed by the master can be received through a multi-antenna array and the angle of arrival can be used to determine the driving direction for follow-up driving.

According to an additional aspect, the driving direction is determined by measuring the angle of arrival of the RF signal received through the short-range wireless communication unit, while the location information of the mobile communication terminal held by the master is received from the data received through the same short-range wireless communication unit. It can be used to calculate the driving direction.

According to an additional aspect, the follower robot may determine the robot's driving direction based on location information received through short-distance wireless communication from a mobile communication terminal possessed by the master and location information output from the robot's position sensor.

According to an additional aspect, the follower robot may run according to movement trajectory information received through short-range wireless communication from the master's mobile communication terminal.

According to an additional aspect, the follower robot may drive autonomously according to destination information received through short-range wireless communication from the master's mobile communication terminal.

According to the proposed invention, the follower robot can determine the direction of movement through short-distance wireless communication with the mobile communication terminal possessed by the master, thereby achieving relatively stable follow-up driving.

Figure 1 is a block diagram showing the configuration of a tracking robot according to an embodiment.
Figure 2 is a block diagram showing the configuration of a tracking robot according to another embodiment.
Figure 3 is a block diagram showing the configuration of a follower robot according to another embodiment.

The foregoing and additional aspects are embodied through embodiments described with reference to the accompanying drawings. It is understood that the components of each embodiment can be combined in various ways within the embodiment or with components of other embodiments as long as there is no other mention or contradiction between them. Based on the principle that the inventor can appropriately define the concept of terms in order to explain his or her invention in the best way, the terms used in this specification and claims have meanings that correspond to the description or proposed technical idea. It must be interpreted as a concept. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

<Claim 1 Description of Invention>

Figure 1 is a block diagram showing the configuration of a tracking robot according to an embodiment. In the illustrated embodiment, the travel drive system 10 represents a mechanically manufactured configuration, and the antenna 30, matching circuit 50, and travel drive unit 900 are implemented as electrical elements mounted on a circuit board. You can. In addition, the robot position calculation sensor 70 is a GPS module that is modularized and implemented on a separate board and can be connected to the main circuit board through a connector. The remaining blocks can be implemented with circuits embedded in a system-on-chip (SoC) and programs stored in its internal memory and executed on an internal processor.

According to one aspect, the RF signal transmitted by the short-range communication module of the mobile communication terminal possessed by the master may be received through a multi-antenna array and the angle of arrival may be used to determine the driving direction for follow-up driving. The Bluetooth LE (Low Energy) standard introduced direction finding technology using real time location systems (RTLS). This technology can provide relative direction information of the transmitting Bluetooth terminal by calculating AOA (Angle of Arrival) from antennas received through array antennas arranged with a phase difference. This technology has been implemented by several semiconductor companies and is provided as a commercialized system-on-chip product. This embodiment can be implemented with the nRF5340 chip from Nordic Semiconductor.

As shown in FIG. 1, the tracking robot according to one embodiment includes a traveling driving unit 900, an array antenna 30, a short-range wireless communication unit 500, a first traveling direction calculation unit 110, and a traveling Includes a controller 300.

The travel drive unit 900 drives a plurality of motors that drive the robot. In one embodiment, the travel driving unit 900 connects each motor to a semiconductor switch that drives forward and reverse and controls the driving current based on the duty ratio of the PWM pulse. The array antenna 30 is arranged with a phase difference on the circuit board and receives the RF signal. Ultra-small array antennas patterned on circuit boards are known. In the illustrated embodiment, array antenna 30 is tuned to the 2.4 GHz band, which complies with the Bluetooth Low Energy 5.1 standard. The short-range wireless communication unit 500 is connected to the mobile communication terminal owned by the master through the array antenna 30, and outputs directional information from the received RF signal. In one embodiment, the short-range wireless communication unit 500 may be implemented with the above-described SoC. According to the Bluetooth low-power standard, the short-range wireless communication unit 500 is a transmitter from RF signals received by an array antenna, here, a short-range wireless communication unit 500 of the follower robot from a Bluetooth tag embedded in a master mobile communication terminal, for example, a smartphone. That is, the angle of arrival (AoA: Angle of Arrival) to the Bluetooth module is calculated and output.

The first driving direction calculation unit 110 calculates the driving direction for following driving from the direction information output from the short-range wireless communication unit 500. In one embodiment, the first driving direction calculation unit 110 determines a driving direction to follow the master based on direction information output from the short-range wireless communication unit 500 to the mobile communication terminal possessed by the master. Additionally, the first driving direction calculation unit 110 can recognize surrounding objects from the camera 20 and determine a driving direction to follow the master while avoiding the objects. Surrounding objects may be, for example, people other than the master, fixed obstacles, moving obstacles, etc. Driving technology for avoiding such obstacles is disclosed, for example, in Patent Publication No. 2020-0080396 published on July 7, 2020.

The travel controller 300 generates a drive signal according to the calculated travel direction and outputs it to the travel driver. The travel controller 300 determines the driving torque, that is, the driving current, of each motor according to the direction from the current position to the master's position, the relative distance, and the rate of change of the relative distance with respect to time, that is, the relative speed, and determines the control value. can be output. The travel drive unit 900 controls the duty ratio of the PWM pulse so that the corresponding drive current is output to each motor of the travel drive system 10 accordingly.

<Claim 2 Description of Invention>

In one embodiment, the short-range wireless communication unit 500 may include an array amplifier 535, a phase difference detection circuit 531, and an angle of arrival calculation unit 533. The array amplifier 535 amplifies the signal received from each antenna of the array antenna 30. The received signal is supplied to the array amplifier 535 through the impedance matching circuit 30. The phase difference detection circuit 531 measures the phase difference between Bluetooth RF signals received from the array antenna. In the illustrated embodiment, the array antenna consists of eight antennas.

The angle of arrival calculation unit 533 calculates the angle of arrival from the phase difference. If the distance between antennas is d and the measured phase difference is ψ, the angle of arrival θ is

θ = arccos(ψλ/2πd)

It can be obtained through the formula. In an array antenna, precision can be increased by excluding values with obvious errors among the angle of arrival values obtained for each antenna pair and averaging them. There is a high possibility that errors will occur in calculating the angle of arrival due to the multi-path effect, etc., so the true value must be estimated through several measurement attempts.

<Claim 3 Description of Invention>

According to an additional aspect, the driving direction is determined by measuring the angle of arrival of the RF signal received through the short-range wireless communication unit, while the location information of the mobile communication terminal held by the master is received from the data received through the same short-range wireless communication unit. It can be used to calculate the driving direction.

Figure 2 is a block diagram showing the configuration of a follower robot according to another embodiment. In the illustrated embodiment, similar components corresponding to Figure 1 are referred to by the same reference numerals. In this embodiment, the short-range wireless communication unit may further include a demodulation unit 551 and a data reception unit 553. The demodulator 551 is a demodulation circuit according to the Bluetooth low power standard and demodulates at least one of the signals output from the array amplifier 535 to output digital data. The data receiver 553 extracts and outputs information from the demodulated digital data.

<Claim 4 Description of Invention>

According to an additional aspect, the follower robot may determine the robot's driving direction based on location information received through short-distance wireless communication from a mobile communication terminal possessed by the master and location information output from the robot's position sensor. Mobile communication terminals are equipped with their own positioning system on a cell-by-cell basis based on a base station, and have a built-in GPS receiver to provide precise positioning information. When the master is far outside the tracking range, the master's location information can help the follower robot follow. In the illustrated embodiment, the follower robot may further include a robot position calculation sensor 70 and a second traveling direction calculation unit 110.

The robot position calculation sensor 70 calculates the position of the robot from positioning information received from a positioning satellite. In one embodiment, the robot position calculation sensor 70 may include a GPS receiver. The second driving direction calculation unit 110 calculates the robot from the location information of the mobile communication terminal, that is, the location information of the master, and the location information of the robot output from the robot position calculation sensor 30 among the information received from the data receiving unit 553. Calculate the driving direction of . At this time, it is common to determine the driving direction according to the vector heading from the robot to the master, but if there are obstacles around, the driving direction can be determined in a different direction.

<Claim 5 Description of Invention>

According to an additional aspect, the follower robot may further include a sensor selection unit 170. The sensor selection unit 170 selects highly reliable information from among the driving directions calculated by the first driving direction calculation unit 110 and the second driving direction calculation unit 130 and outputs it to the driving controller 150. In one embodiment, the sensor selection unit 170 preferentially selects the output of the first driving direction calculation unit 110 when the distance between the following robot and the master is less than or equal to the reference distance. That is, at short distances, it is driven to travel in the direction determined by the angle of arrival. The sensor selection unit 170 preferentially selects the output of the second driving direction calculation unit 130 when the distance between the following robot and the master is greater than the standard distance, but as GPS reception is not possible in an indoor environment, the second driving direction is selected. If the output of the calculation unit 130 is not normal, the output of the first driving direction calculation unit 110 can be selected.

<Claim 6 Description of Invention>

According to an additional aspect, the follower robot may run according to movement trajectory information received through short-range wireless communication from the master's mobile communication terminal. Figure 3 is a block diagram showing the configuration of a follower robot according to another embodiment. In the illustrated embodiment, similar structures corresponding to Figure 1 or Figure 2 are referred to by the same reference numerals. In the illustrated embodiment, the follower robot includes an instruction trajectory traveling unit 120. The indicated trajectory driving unit 120 continuously outputs the driving direction to the driving controller 150 according to the movement trajectory information among the data received through the data receiving unit 553.

In one embodiment, the instruction trajectory driving unit 120 takes control of the driving controller 150 based on the movement trajectory information received from the mobile communication terminal possessed by the master through the short-distance wireless communication unit 500 and continuously Movement commands can be output. The movement trajectory may be, for example, the starting point and destination entered on the map by the master by running the app on the mobile communication terminal, and the movement trajectory calculated by the app itself or through a server. The movement command may include only the direction of movement or may include movement speed or acceleration. Additionally, the instruction trajectory driving unit 120 receives direction information output from the short-range wireless communication unit 500, location information of objects recognized from images input from the camera 20, and input from the robot position calculation sensor 70. Driving that follows the received movement trajectory can be controlled based on the received location information. For example, if an obstacle appears while moving along the travel path, the vehicle can deviate from the travel path, avoid the obstacle, and then return to the travel path.

<Claim 7 Description of Invention>

According to an additional aspect, the follower robot may drive autonomously according to destination information received through short-range wireless communication from the master's mobile communication terminal. In the embodiment shown in FIG. 3, the follower robot includes an autonomous driving unit 140. The autonomous driving unit 140 calculates a driving trajectory on the map according to destination information among the data received through the data receiving unit 553 and continuously outputs the driving direction accordingly to the driving controller.

In one embodiment, the autonomous driving unit 140 calculates a movement route based on destination information received from a mobile communication terminal owned by the master through the short-range wireless communication unit 500, and then grants control to the driving controller 150. You can take control and continuously output movement commands. The movement path may be calculated by the follower robot using its own calculation elements, or it may be calculated through a map information provision server. The movement command may include only the direction of movement or may include movement speed or acceleration. Additionally, the autonomous driving unit 140 receives direction information output from the short-range wireless communication unit 500, location information of objects recognized from images input from the camera 20, and information input from the robot position calculation sensor 70. Driving that follows the movement path can be controlled based on location information. For example, if an obstacle appears while moving along the travel path, the vehicle can deviate from the travel path, avoid the obstacle, and then return to the travel path.

In the above, the present invention has been described through embodiments with reference to the accompanying drawings, but it is not limited thereto, and should be interpreted to encompass various modifications that can be easily derived by those skilled in the art. The claims are intended to cover these variations.

10: Driving system 20: Camera
30: array antenna 50: matching circuit
70: Robot position calculation sensor
110: first driving direction calculation unit 120: instruction trajectory driving unit
130: Second driving direction calculation unit 140: Autonomous driving unit
150: Driving controller 170: Sensor selection unit
500: Short-distance wireless communication department
531: Phase difference detection circuit 533: Angle of arrival calculation unit
551: Demodulation unit 553: Data reception unit
555: Array amplifier
900: Travel driving unit

Claims (7)

In the follower robot that follows the master and runs, the follower robot:
a travel driving unit that drives a plurality of motors to drive the robot;
an array antenna arranged with a phase difference on a circuit board to receive an RF signal;
a short-distance wireless communication unit that is connected to a mobile communication terminal owned by the master through the array antenna and outputs directional information from the received RF signal;
a first driving direction calculation unit that calculates a driving direction for following driving from the direction information output from the short-range wireless communication unit;
A follower robot including a travel controller that generates a drive signal according to the calculated travel direction and outputs it to the travel drive unit. The method in claim 1, wherein the short-range wireless communication unit:
an array amplifier that amplifies each RF signal received from the array antenna;
a phase difference detection circuit that detects a phase difference between the amplified RF signals;
An angle of arrival calculation unit that calculates an angle of arrival (AOA) from the detected phase difference;
A follower robot including. In claim 2, the short-range wireless communication unit:
a demodulator that demodulates at least one of the signals output from the array amplifier and outputs digital data;
a data receiving unit that extracts and outputs information from the digital data output from the demodulator;
A follower robot further comprising: The method of claim 3, wherein the follower robot:
a robot position calculation sensor that calculates the position of the robot from positioning information received from a positioning satellite;
A tracking robot further comprising a second driving direction calculation unit that calculates the driving direction of the robot from the position information of the mobile communication terminal received from the data reception unit and the position information of the robot output from the robot position calculation sensor. The method of claim 4, wherein the follower robot:
a sensor selection unit that selects highly reliable information from among the driving directions calculated by the first driving direction calculation unit and the second driving direction calculation unit and outputs it to the driving controller;
A follower robot further comprising: The method of claim 3, wherein the tracking driving controller:
an instruction trajectory driving unit that continuously outputs the driving direction to the driving controller according to the movement trajectory information among the data received through the data receiving unit;
A follower robot further comprising: The method of claim 3, wherein the tracking driving controller:
an autonomous driving unit that calculates a driving trajectory on the map according to destination information among the data received through the data receiver and continuously outputs the driving direction to the driving controller accordingly;
A follower robot further comprising: