JP2023167780A - Robot control system, transport system, and robot control method - Google Patents

Abstract

To increase the accuracy in estimating a self position of a robot including a first sensor and a second sensor by using information calculated from the second sensor when position information from the first sensor cannot be used.SOLUTION: In a robot control system in which a server including a processor and a memory estimates a position of a robot, the robot includes a first sensor for acquiring first sensing information and a second sensor for acquiring second sensing information, and the server includes: a storage unit in which a first position obtained from the first sensing information, first travel state information including a first attitude, second travel state information including a second speed and a second angular speed of the robot obtained from the second sensing information, and correspondence relation information indicative of a correspondence relation between the first travel state information and the second travel state information are stored in association with the first position; and a calculation unit which calculates an estimated position of the robot on the basis of the first travel state information and the second travel state information.SELECTED DRAWING: Figure 3A

Description

The present invention relates to a technique for correcting the self-position of a robot.

As a self-position estimation method for automatic guided vehicles (AGVs), there are methods that combine multiple self-position estimation methods to improve accuracy and robustness, such as Visual SLAM (SLAM) using image feature points. A technology is known that combines a Simultaneous Localization and Mapping method (first self-position estimation method) and a wheel odometry method (hereinafter referred to as odometry) using wheel rotation information (encoder information) (second self-position estimation method). ing.

Patent Document 1 discloses that a calculation accuracy map of a first self-position obtained by an image processing-based self-position estimation process and a second self-position obtained by an odometry-based self-position estimation process is created in advance. , a self-position estimation method is disclosed in which a combination ratio of a first self-position and a second self-position is determined using calculation accuracy written in a calculation accuracy map.

On the other hand, according to FIG. 5 of Patent Document 1, when a predetermined number or more of landmarks cannot be detected, that is, when the first self-position cannot be obtained due to an error, only the second self-position is used. A method for estimating self-position is disclosed.

Patent Document 2 or Non-Patent Document 1 describes the basic function of Visual SLAM using image feature points, specifically, detecting a group of image feature points from continuous camera images, and A function for creating a map while estimating one's own position by tracking between frames is disclosed. Furthermore, a function for estimating one's own position with high accuracy by comparing camera images with a map created using the basic functions of Visual SLAM is also disclosed.

JP2021-96731A Japanese Patent Application Publication No. 2017-146952

Shinya Sumikura, Mikiya Shibuya, and Ken Sakurada, "OpenVSLAM: A Versatile Visual SLAM Framework", Open Source Software Competition, October 21-25, 2019, Nice

Patent Document 1 discloses a method of estimating the self-position using only the second self-position when the first self-position cannot be obtained due to an error. The second self-position obtained by the odometry-based self-position estimation process is susceptible to the effects of friction and unevenness on the road surface (or floor surface), wear and tear of the wheels, etc. The accuracy of position estimation is lower than the self-position in No. 1.

Therefore, when the second self-position is used, there is a problem in that errors accumulate with respect to the first self-position that would have been obtained if no error occurred.

The present invention has been made in view of the above-mentioned problems, and when controlling a robot having a first sensor and a second sensor of different types, the first self-position calculated from the first sensor is It is an object of the present invention to improve the accuracy of estimating one's own position using information calculated from a second sensor when the second sensor is unavailable.

The present invention is a robot control system in which a server having a processor and a memory estimates the position of a mobile robot, wherein the mobile robot has a first sensor unit that acquires first sensing information from the traveling state of the mobile robot. and a second sensor unit that has a sensor different from the first sensor unit and acquires second sensing information from the running state of the mobile robot, and the server has information on a first running state including a first position and a first attitude at the first position obtained from sensing information; and a second speed and a second speed of the mobile robot obtained from the second sensing information. a storage unit that stores correspondence relationship information indicating a correspondence relationship between information on a second running state including information on an angular velocity of the second drive state in association with the first position; a calculation unit capable of calculating an estimated position of the mobile robot based on information on a second running state, the calculation unit configured to calculate an estimated position of the mobile robot based on the first sensing information acquired from the first sensor unit. Information on the first position and the first posture is calculated, and if an error occurs when calculating the first position, information on the second driving state acquired from the second sensing information is calculated. An estimated position of the mobile robot is calculated based on the information and the correspondence information.

Therefore, in the present invention, even if the first position cannot be obtained from the first sensing information of the first sensor unit due to an error, the speed ratio of the second sensing information of the second sensor unit and the correspondence information The position of the mobile robot can be calculated using the angular velocity ratio and the angular velocity ratio with the same accuracy as the first position.

The details of at least one implementation of the subject matter disclosed herein are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the disclosed subject matter will be apparent from the following disclosure, drawings, and claims.

1 is a diagram illustrating a motion model of a robot according to a first embodiment of the present invention; FIG. 1 is a diagram illustrating a first embodiment of the present invention and showing a relationship between a robot's trajectory and its own position; FIG. FIG. 1 is a diagram illustrating the speed and angular velocity of a robot according to a first embodiment of the present invention. 1 is a block diagram showing an example of hardware of a robot control system according to a first embodiment of the present invention; FIG. 1 is a perspective view of a robot, showing Example 1 of the present invention; FIG. Embodiment 1 of the present invention is shown and is a side view of a robot. 1 is a block diagram showing an example of software of a robot control system according to a first embodiment of the present invention; FIG. 1 is a flowchart showing an example of self-position correction processing according to a first embodiment of the present invention. 1 is a flowchart illustrating a first embodiment of the present invention and illustrating an example of a database search process. FIG. 3 is a diagram illustrating the first embodiment of the present invention and illustrating an example of correction information when traveling straight. FIG. 3 is a diagram showing an example of correction information in the case of a right turn, showing Example 1 of the present invention. 1 is a flowchart illustrating a first embodiment of the present invention and illustrating an example of correction information in a database. FIG. 3 is a diagram illustrating the first embodiment of the present invention and illustrating an example of correction information for each movement type in the case of a right turn.

Embodiments of the present invention will be described below with reference to the drawings. The examples are illustrative for explaining the present invention, and are omitted and simplified as appropriate for clarity of explanation. The present invention can also be implemented in various other forms. Unless specifically limited, each component may be singular or plural. The position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. in order to facilitate understanding of the invention. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

Examples of various types of information will be described using expressions such as "table," "list," and "queue," but various information may also be expressed using data structures other than these. For example, various information such as "XX table", "XX list", "XX queue", etc. may be referred to as "XX information". When describing identification information, expressions such as "identification information", "identifier", "name", "ID", and "number" are used, but these expressions can be replaced with each other.

When there are multiple components having the same or similar functions, the same reference numerals may be given different suffixes for explanation. Furthermore, if there is no need to distinguish between these multiple components, the subscripts may be omitted from the description.

In the embodiments, processing performed by executing a program may be explained. Here, a computer executes a program using a processor (eg, CPU, GPU), and performs processing determined by the program using storage resources (eg, memory), interface devices (eg, communication port), and the like. Therefore, the main body of processing performed by executing a program may be a processor. Similarly, the subject of processing performed by executing a program may be a controller, device, system, computer, or node having a processor. The main body of the processing performed by executing the program may be an arithmetic unit, and may include a dedicated circuit that performs specific processing. Here, the dedicated circuit is, for example, an FPGA (Field Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), or a CPLD (Complex Programmable Logic Device).

A program may be installed on a computer from a program source. The program source may be, for example, a program distribution server or a computer-readable storage medium. When the program source is a program distribution server, the program distribution server includes a processor and a storage resource for storing the program to be distributed, and the processor of the program distribution server may distribute the program to be distributed to other computers. Furthermore, in the embodiments, two or more programs may be implemented as one program, or one program may be implemented as two or more programs.

The present invention provides an automatic guided vehicle that runs autonomously, even if the first self-position (self-position 1) calculated from the first sensor cannot be obtained due to an error, the driving state calculated from the second sensor The self-position is restored from the first self-position with the same accuracy as the first self-position.

Note that an automatic guided vehicle (AGV) is referred to as a robot in this embodiment. Further, it is assumed that the first sensor and the second sensor are composed of different types of sensors, and the positional accuracy calculated from the first sensor is higher than the positional accuracy calculated from the second sensor.

The self-position restoration method will be explained using FIG. 1A. Equation 100 shown in FIG. 1A is a motion model of a two-wheel differential drive robot 300. The robot 300 travels in an XY two-dimensional space and changes its traveling direction by turning. The position of the robot 300 is indicated by x and y coordinates, the direction is indicated by θ, the speed is indicated by ν, and the angular velocity is indicated by ω.

The above equation 100 represents the position and orientation of the robot 300 (x(t-1), y(t-1), θ(t-1)) at times t=1, 2, 3, 4,... Using the velocity (ν(t)) and angular velocity (ω(t)) as input, calculate the position and orientation (x(t), y(t), θ(t)) of the robot 300 at the next step (time). This is a formula that expresses the trajectory of the robot 300.

In this embodiment, the variable x and the subscript t in equation 100 are expressed as x(t). Variables y, θ, etc. and subscripts are similarly written as y(t) and θ(t). Furthermore, the subscript (t) may be omitted.

FIG. 1B is a diagram showing the relationship between the trajectory of the robot 300 and its own position. A trajectory 101 in the figure is a trajectory of a self-position 1 calculated from a velocity 1 (v1) and an angular velocity 1 (ω1) (110) obtained from a first sensor (described later). The trajectory 102 is the trajectory of the self-position 2 calculated from the velocity 2 (v2) and the angular velocity 2 (ω2) (111) obtained from the second sensor.

Although the sensor for self-position 1 is highly accurate, an error called self-position lost, in which the sensor loses sight of self-position 1, is likely to occur. On the other hand, the sensor for self-position 2 does not generate an error, but it is likely to cause an error in the self-position.

As described above, since the velocity and angular velocity obtained from two types of sensors having different performance and accuracy do not necessarily match, a deviation 103 occurs in the trajectories of the two. The deviation 103 is the difference between velocity 1 (ν1) and velocity 2 (ν2), and angular velocity 1 (ω1) and angular velocity 2 (ω2), which are input at each step (t=1, 2, 3, 4, ...). It is the cumulative distance caused by the difference between

In order to perfectly match the trajectories 101 and 102, as shown in equation 112 in FIG. Note that the speed ratio (v1/v2) and the angular speed ratio (ω1/ω2) may be multiplied by the speed 2 (v2) and the angular speed ratio (ω2), respectively.

However, in reality, it is difficult to perfectly match the trajectory 101 and the trajectory 102, so an attempt is made to approximate the trajectory using the following method.

First, the speed ratio (ν1/ν2) and angular velocity ratio (ω1/ω2) when self-position 1 is normally obtained are expressed as the position and orientation of the robot 300, velocity 2, and angular velocity 2 (x, y, θ, ν2). , ω2) and are registered in the correction information of a database (hereinafter referred to as DB).

If self-position 1 cannot be obtained due to an error etc., the speed closest to the current robot state (x, y, θ, ν2, ω2) is selected from the speed ratios and angular velocity ratios registered in the DB. The ratio and angular velocity ratio are searched and used for correction. Specifically, the velocity 1 and angular velocity 1 that would have been obtained if no error had occurred are approximated and calculated using the following equations.

Velocity 1 (approximation) = Velocity 2 × velocity ratio obtained by searching from DB Angular velocity 1 (approximation) = Angular velocity 2 × angular velocity ratio obtained by searching from DB

By applying velocity 1 (approximation) and angular velocity 1 (approximation) calculated from the above equation to equation 100 above, self-position 1 (approximation) can be calculated. Therefore, with this method, even if self-position 1 cannot be obtained due to an error, a self-position (corrected self-position) with the same accuracy as self-position 1 can be restored from the velocity and angular velocity at self-position 2. Note that the self-position 2 indicates the position and orientation when an error occurs at the timing when the robot 300 acquires the self-position 1.

The hardware configuration of the robot 300 and the robot control system in the embodiment of the present invention will be described using FIGS. 3A to 3C. FIG. 3A is a block diagram illustrating an example of hardware of the robot control system. 3B is a perspective view of the robot 300, and FIG. 3C is a side view of the robot 300.

The robot control system of the present invention is composed of a robot 300 and a server 320. Although this embodiment will be explained using a simple example of one robot and one server, it is also applicable to a large-scale robot control system using a plurality of robots 300 and a plurality of servers 1.

The robot 300 is an automatic guided vehicle (AGV) whose purpose is to transport cargo in a distribution warehouse. The robot 300 supports a stereo camera 301, wheels 303 (driving wheels), an encoder 302, a lifter 304 for lifting and lowering cargo, a wheel motor 306 for driving wheels, a battery 305, a PC 1 (307), a power source 308, and a load. Consists of a driven wheel (not shown).

The PC 1 (307) is a well-known computer that includes a CPU, a memory, a storage device such as an SSD (Solid State Drive), and WiFi (or a wireless communication unit). The robot 300 of this embodiment is a differential two-wheeled robot that moves straight and rotates using two wheels 303, and includes two sets each of wheels 303, encoders 302, and wheel motors 306.

Note that the two wheels 303 are arranged in parallel with respect to the straight traveling direction, and two encoders 302 are attached to each. The battery 305 supplies power to the wheel motor 306, and the power supply 308 supplies power to PC1 (307).

The server 320 includes a PC 2 (321) and a power supply 322. The PC2 (321) is a well-known computer composed of a CPU, memory, SSD, WiFi, etc.
The robot 300 and the server 320 are connected via wireless LAN and can communicate using a predetermined protocol (eg, TCP).

The robot 300 of this embodiment is equipped with two types of sensors for recognizing its own position. The first sensor is a stereo camera 301. In this embodiment, the server 320 calculates the self-position (self-position 1) from the image of the stereo camera 301 using the Visual SLAM function described in Non-Patent Document 1. The Visual SLAM function will be described later.

The second sensor is a pair of encoders 302. The rotation angles of the left and right wheels 303 are obtained from the pair of encoders 302, and the server 320 calculates the speed and angular velocity from the encoder values. A method for calculating self-position 1 will be described later.

Next, the software configuration of the robot 300 and the robot control system in the first embodiment of the present invention will be described using FIG. 4. FIG. 4 is a block diagram showing an example of software of the robot control system.

In the figure, block 400 shows the software configuration that runs on the robot 300, and block 420 shows the software configuration that runs on the server 320. These software run on a Linux OS (not shown).

First, a method for calculating self-position 1 will be explained. The image acquisition and distribution unit 401 is a program that acquires stereo images from the stereo camera 301 and distributes them to the Visual SLAM 422.

Visual SLAM 422 is a program that calculates self-position 1 using image feature points extracted from stereo images, and functions as a self-position 1 calculation unit. A typical Visual SLAM program is "Open VSLAM: A Versatile Visual SLAM Framework" described in Non-Patent Document 1.

This program has a mode in which map creation and self-position estimation are executed simultaneously, and a mode in which self-position estimation is executed by reading the map created in the above mode and comparing the map with the camera image. The Visual SLAM 422 in this embodiment is assumed to operate in the latter mode.

Specifically, the Visual SLAM 422 reads a map 421 created in advance, compares the map 421 with a stereo image obtained from the stereo camera 301, and estimates the self-position 1.

The Visual SLAM 422 outputs self-position 1 and an error signal as a result of program processing. Self-position 1 is represented by (x, y, θ). x, y indicate the coordinates of the robot 300 on the map 421, and θ is the direction of the robot 300 (Equation 100 in FIG. 1A).

The error signal is output from the Visual SLAM 422 when matching the map 421 and the stereo camera image fails. That is, the Visual SLAM 422 sets the error signal to "1" when the self-position 1 is not obtained, and sets the error signal to "0" when the self-position 1 is obtained and outputs it. The self-position 1 and the error signal are distributed to the self-position correction unit 426 at a frequency of, for example, 30 times per second.

Next, a method of calculating velocity 2 and angular velocity 2 from the encoder 302 will be described. The encoder value acquisition and distribution unit 402 is a program that reads an encoder value representing the rotation angle of the wheel 303 from the encoder 302 and distributes it to the velocity 2 and angular velocity 2 calculation unit 423.

The velocity 2 and angular velocity 2 calculation unit 423 acquires and distributes the encoder values of the left and right wheels 303 about 100 times per second. The speed 2 and angular velocity 2 calculation unit 423 calculates the travel distance of each wheel 303 per unit time from the amount of increase or decrease in the encoder value per unit time.

The distance traveled when the wheel 303 makes one rotation (360 degrees) can be calculated by multiplying the diameter of the wheel 303 by the circumference, so by calculating the rotation angle of the wheel 303 from the output of the encoder 302, the distance traveled by the robot 300 can be calculated by calculating the rotation angle of the wheel 303 from the output of the encoder 302. Can calculate.

The velocity 2 and angular velocity 2 calculation unit 423 calculates the velocity 2 (ν2) and angular velocity 2 (ω2) of the robot 300 from equation 200 in FIG. 2, where the left wheel travel distance is dl and the right wheel travel distance is dr. The calculated velocity 2 (ν2) and angular velocity 2 (ω2) are distributed to the self-position correction unit 426.

The self-position correction unit 426 inputs the self-position 1 and error signal distributed from the Visual SLAM 422, and the velocity 2 and angular velocity 2 distributed from the velocity 2 and angular velocity 2 calculation unit 423, and stores them in the database (DB) 425. This is a program that uses correction information 702 to output a corrected self-position (estimated position and estimated orientation) when self-position 1 cannot be obtained due to an error. Details of this program will be described later.

On the other hand, the route following program 427 is a program that causes the robot 300 to travel along a preset route using the corrected self-position and route information. The route following program 427 generates information for driving the wheel motors 306, and drives the wheel motors 306 via the motor drive information distribution section 424 and the motor drive section 403. It should be noted that since the route following program 427, the motor drive information distribution section 424, and the motor drive section 403 may use well-known or well-known techniques, a detailed description of the functions will be omitted. This concludes the explanation of the software blocks.

Next, details of the process performed by the self-position correction unit 426 will be described using FIG. 5. FIG. 5 is a flowchart illustrating an example of self-position correction processing. This process consists of three processes: a main loop process (500), a correction information registration process 510, and a self-position correction process 520.

Correction information registration processing 510 is a correction for restoring a self-position (corrected self-position) with the same accuracy as the first self-position (self-position 1) from the velocity and angular velocity when the error signal becomes "1". This is a process of registering information 702 (see FIG. 7C), and the self-position correction process 520 is a process of correcting the self-position using the registered correction information.

First, the main loop processing (from start 500 to end 508) will be explained. The program starts at start 500, and in the subsequent process 501, the self-position correction unit 426 initializes the variable "previous self-position" to (0, 0, 0). “Previous self-position” is a variable representing the position and orientation (x, y, θ) of the robot 300, and stores the position and orientation of the robot 300 one step before.

In the next process 502, the self-position correction unit 426 waits until it receives the self-position 1 and an error signal. The self-position 1 and error signal are transmitted from the Visual SLAM 422 at a frequency of 30 times per second, for example.

Self-position 1 is the position and orientation (x, y, θ) of the robot 300 obtained from the Visual SLAM 422. When the error signal is "0", it indicates that no error has occurred, and when it is "1", it indicates that an invalid value is set in self-position 1 because an error has occurred.

After receiving the self-position 1 and the error signal, the self-position correction unit 426 proceeds to processing 503. In process 503, the self-position correction unit 426 acquires the velocity 2 and angular velocity 2 transmitted from the velocity 2 and angular velocity 2 calculation unit 423. The velocity 2 and the angular velocity 2 are the velocity 2 and the angular velocity 2 of the robot 300 calculated from the rotation information of the wheels 303, as described above.

In process 504, the error signal is "0" (self-position 1 was obtained without an error occurring), and the DB registration flag (described later) is "1" (registration is performed in the correction information 702 of the database 425). The conditions are determined, and if the determination result is Yes, correction information registration processing 510 is executed.

The DB registration flag is assumed to be specified by the user as "0" or "1" in the program startup argument, but it is not possible to set it to "0" or "1" according to predetermined conditions during program execution. good. Details of the correction information registration process 510 will be described later.

If the determination result in process 504 is No, in process 505 it is determined whether or not self-position correction process 520 is to be executed. Specifically, when the error signal is "1" (an error occurred and self-position 1 was not obtained), self-position correction processing 520 is executed. Details of the self-position correction process 520 will be described later.

In the next process 506, the self-position correction unit 426 updates the previous self-position in order to use self-position 1 as the previous self-position in the next step. Furthermore, the self-position correction unit 426 outputs self-position 1 as a corrected self-position. The corrected self-position is the position and orientation (x, y, θ) of the robot 300 after being corrected in the self-position correction process 520, and if the error signal = "0", it becomes self-position 1 without correction.

In the next process 507, a program termination determination is executed, and if YES, the process advances to termination 508 and the program is terminated. If No, the process returns to step 502 and the program continues. In the program termination determination, the self-position correction unit 426 determines whether or not a preset termination condition is satisfied.

In this embodiment, a series of processes from process 502 to process 507 is expressed as one step. One step is executed, for example, at a cycle of 1/30 second, which is the reception cycle of self-position 1. The above is the main loop processing.

Next, the correction information registration process 510 will be explained. If the self-position 1 is correctly obtained without an error occurring in process 504, and the DB registration flag is set to "1" (valid), this process is executed.

In process 511, the self-position correction unit 426 uses the following equation 201 to calculate velocity 1 (v1) and angular velocity 1 (ω1) from the previous self-position and self-position 1 at each time t.

Specifically, the previous self-position = (x (t-1), y (t-1), θ (t-1)), and the self-position 1 = (x (t), y (t), θ ( t)) and substitute Δt=1/30 second into the above equation 201 to calculate velocity 1 (ν1) and angular velocity 1 (ν1).

In the next process 512, the self-position correction unit 426 calculates a speed ratio from speed 1 and speed 2, and an angular speed ratio from angular speed 1 and angular speed 2. Furthermore, in the next process 513, the self-position correction unit 426 converts the speed ratio and angular velocity ratio into the previous self-position (x(t-1), y(t-1), θ(t-1)), velocity 2( ν2) and angular velocity 2 (ω2) and are registered in the correction information 702 of the DB 425. The above is the correction information registration process 510.

Next, self-position correction processing 520 will be explained. The self-position correction process 520 is executed when an error occurs and the self-position 1 cannot be obtained in the process 505.

In process 521, the self-position correction unit 426 uses the previous self-position (x, y, θ), velocity 2 (ν2), and angular velocity 2 (ω2) as search keys, and uses the most matching velocity ratio and angular velocity ratio as correction information in the DB 425. Search from 702. Details of this process will be described later.

If a speed ratio and an angular velocity ratio are obtained as a search result, the process branches to the Yes side in the determination of process 522. If the speed ratio and angular speed ratio are not obtained, the process branches to the No side, and in step 532, speed ratio=1.0 and angular speed ratio=1.0 are set. In the next process 524, the estimated value of velocity 1 and the estimated value of angular velocity 1 that would have been obtained if no error had occurred are calculated using the following equation 202.

Velocity 1 = Velocity 2 x Velocity ratio Angular velocity 1 = Angular velocity 2 x Angular velocity ratio ... (202)

In the next process 525, the self-position correction unit 426 calculates the self-position 1 (estimated position and estimated attitude) from the previous self-position, the estimated value of velocity 1, and the estimated value of angular velocity 1 using equation 100 in FIG. Specifically, (x(t-1), y(t-1), θ(t-1)) = previous self-position, ν(t) = velocity 1 (ν1), ω(t) = angular velocity 1 Self-position 1 (x(t), y(t), θ(t)) is calculated by setting (ω1) and Δt=1/30th of a second.

When the process 525 ends, the process advances to a process 506. The above is the self-position correction processing 520.

Note that if the error continues to occur, the self-position correction unit 426 generates correction information using self-position 1 (estimated position and estimated orientation), velocity 2 (ν2) at the estimated position, and angular velocity 2 (ω2) at the estimated orientation. 702 and obtain the velocity ratio and angular velocity ratio from the search results as described above.

Then, the self-position correction unit 426 calculates the estimated value of velocity 1 (ν1) at the estimated position and the angular velocity at the estimated attitude from the acquired speed ratio and angular velocity ratio, velocity 2 (ν2) at the estimated position, and angular velocity (ω2) at the estimated attitude. 1 (estimated value of ω1), and self-position 1 is calculated based on the estimated value of velocity 1 (v1) at the calculated estimated position and the estimated value of angular velocity 1 (ω1) at the estimated posture.

Next, details of the DB search process of process 521 in FIG. 5 will be explained using FIG. 6. This process is implemented, for example, as a function, and the argument 600 in the figure is the argument of the function.

Set the position and orientation (x, y, θ) of the robot 300 in the argument search keys ix, iy, iθ, set the velocity 2 (ν2) and angular velocity 2 (ω2) in iν2, iω2, and set the search range. For s1, s2, s3, s4, and s5, set the search range of ix, iy, iθ, iν2, and iω2, and for mode, set mode = 0 to return the velocity and angular velocity with the highest matching degree. , to return the average of the matched velocity and angular velocity, set modo=1 as an argument and execute this function.

In process 601, the self-position correction unit 426 calculates the speed ratio and angular speed ratio near the current position (x, y) of the robot 300 from among the speed ratio and angular speed ratio stored in the correction information 702 of the DB 425 under the following conditions. Search using formula 203.

(ix-s1<x<ix+s1) and (iy-s2<y<iy+s2)
...(203)

Note that s1 and s2 are constants for searching for data in the vicinity (predetermined range) of positions ix and iy, which are search keys, and are set in advance.
If the self-position correcting unit 426 finds even one speed ratio and angular velocity ratio, it branches to the Yes side in process 602, and if it is not found, it branches to the No side.

In process 603, the self-position correction unit 426 further narrows down and searches for records that satisfy the following conditional expression 204 regarding direction, speed ratio, and angular speed ratio from among the correction information 702 hit in the above search.

(iθ−s3 < θ < iθ+s3) and
(iν2-s4 < ν2 < iν2+s4) and
(iω2-s5 < ω2 < iω2+s5) ......(204)

Note that s3, s4, and s5 are constants for searching for data in the vicinity (predetermined range) of the direction θ, velocity 2ν2, and angular velocity 2ω2, which are the second search keys, and are set in advance.

Since a DB search using a large number of search keys slows down the search speed, in this embodiment, the program (self-position correction unit 426) narrows down the search results based on the results of a rough search of the correction information 702 in the DB 425. . If at least one speed ratio and angular velocity ratio is found as a result of the narrowing search, the process branches to the Yes side in step 604, and if none is found, the process branches to the No side.

In process 605, the self-position correction unit 426 branches depending on the search mode. If modo=0, the speed ratio and angular velocity ratio with the highest degree of matching are returned in process 608.

Specifically, the self-position correction unit 426 selects and returns the speed ratio and angular velocity ratio that minimize the Euclidean distance between each variable from among the results obtained by the narrowed search.

If modo=1, in step 607, the self-position correction unit 426 calculates and returns the average of the velocity ratio and angular velocity ratio from the results obtained by the narrowed search. If the process branches to the No side in steps 602 and 604, the self-position correction unit 426 returns “search failure”. The details of the DB search process in process 521 have been described above.

Next, an example of the operation of the robot and the self-position correction unit 426 will be described using FIGS. 7A and 7B. FIG. 7A is a diagram showing an example of correction information when the robot 300 moves straight, and FIG. 7B is a diagram showing an example of correction information when the robot 300 turns right.

In FIG. 7A, a trajectory 700 shows an example in which the robot moves straight in the direction of the arrow, and in FIG. 7B, a trajectory 701 shows an example in which the robot 300 turns right.

When registering the correction information 702, the correction information (previous self position, velocity 2, angular velocity 2, velocity ratio, angular velocity ratio) is registered while the robot 300 is traveling in the direction of the arrow in the figure along the trajectories 700 and 701 in the figure. 702 to the DB425.

The correction information 702 is information in which the position information (P100 to P120 in FIG. 7A, P200 to P260 in FIG. 7B) acquired from the robot 300 during running and the running state at each position are registered.

FIG. 7C is a diagram showing an example of correction information 702. The correction information 702 includes a legend 7021, a position 7022, a direction 7023, a speed 7024, a speed ratio 7025, an angular speed ratio 7026, and a note 7027 in one record.

The legend 7021 stores an identifier set by the server 320. Position 7022 is. The position (x, y) of the robot 300 is stored, and the orientation 7023 stores the orientation θ of the robot 300.

The velocity 7024 stores a search key consisting of velocity 2 (v2) and angular velocity 2 (ω2) obtained from the encoder 302. The speed ratio 7025 stores the speed 2 calculated by the above equation 200. The angular velocity ratio 7026 stores the angular velocity ω2 calculated by the above equation 200. Notes 7027 stores items specified by the server 320.

The correction information 702 is obtained by linking a speed ratio 7025 and an angular velocity ratio 7026 to a search key consisting of a position 7022, an orientation 7023, a velocity 2 (ν2), and an angular velocity 2 (ω2) obtained from the encoder 302 of the robot 300. Store.

In the illustrated example, for convenience of explanation, only a small number of the items of the correction information 702 are registered, but in reality, the robot 300 is run 30 times per second while traveling along a predetermined route, which is converted into the robot's travel distance. Correction information 702 is registered approximately every 2 to 3 cm.

The correction information (P110, P220, P230, P240) shown in FIGS. 7A and 7B is correction information for almost the same location, but the orientation of the robot 300, velocity 2 (ν2), and angular velocity 2 (ω2) are different. Correction information (velocity ratio, angular velocity ratio) is registered according to each state. Roughly speaking, P110 in the figure shows correction information when going straight, P210 in the figure shows correction information when decelerating, P220 in the figure shows correction information when turning clockwise, and P240 in the figure shows correction information when turning clockwise while decelerating. This is correction information.

The robot 300 in the distribution warehouse is considered to travel on a predetermined route. Therefore, by collecting the correction information 702 while traveling on a predetermined route and registering it in the DB 425, the correction information 702 near the robot 300 at the time of error occurrence can be reliably obtained.

FIG. 8 is a diagram illustrating an example of correction information for each movement type in the case of a right turn, etc. In cases such as going straight or turning right, correction information 702 corresponding to the type of movement of the robot 300 is considered necessary.

Trajectories 800L and 800R in the figure are the trajectories of the left and right wheels 303 when the robot 300 moves straight. Trajectories 801L and 801R are the trajectories of the left and right wheels 303 when the robot 300 turns right.

Area 803 is a location where the road surface has a small coefficient of friction and wheels 303 tend to slip. In the illustrated example, the robot 300 does not pass over area 803 when going straight, but does pass when turning right.

When turning right, the wheels 303 tend to slip, so it is thought that the angular velocity ratio (v1/v2) becomes somewhat smaller than 1. On the other hand, when traveling straight, an angular velocity ratio that is extremely close to 1 is considered to be obtained. Therefore, by registering correction information 702 at point 802 that corresponds to the movement type of the robot 300 (go straight, turn right, etc.), even if the robot 300 is at the same location, it can Therefore, it is thought that self-position can be corrected with higher accuracy.

From the above, in the first embodiment of the present invention, even if the first self-position cannot be obtained due to an error, the first self-position can be obtained by correcting the second self-position using the correction information 702. It can be calculated. At this time, even at the same location, the self-position can be calculated with high accuracy according to the position and posture of the robot 300 and the type of movement (direction, straight movement, rotation).

In the first embodiment, the stereo camera 301 is used as the first sensor, and odometry is used as the second sensor. However, the present invention is not limited to this. It is sufficient if it can be detected. For example, LiDAR (Light Detection And Ranging) may be used as the first sensor, and GNSS (Global Navigation Satellite System) may be used as the second sensor if the place where the robot 300 is operated is a place where communication with a satellite is possible.

Further, in the first embodiment, an example was shown in which the server 320 calculates the self-position 1 and corrects the self-position, and drives the wheel motor 306 at the corrected self-position 1. However, the present invention is not limited to this. Although not shown in the figure, the map 421, Visual SLAM 422, velocity 2 and angular velocity 2 calculation section 423, database 425 (correction information 702), self-position correction section 426, route following program 427, and motor drive information distribution section 424 are provided by the robot. 300 to correct the self-position.

Furthermore, the first embodiment can be applied to a conveyance system in which the robot 300 conveys objects such as luggage and products.

Example 2 describes differences from Example 1.

(1) The following items may be added as the correction information 702 to be registered in the DB 425.

By adding the item "date and time", it becomes possible to selectively search for the latest correction information 702. In addition, it is possible to correct for changes in the coefficient of friction over time due to the degree of road surface pain, deterioration of the robot over time, etc.

By adding the items "acceleration" and "angular acceleration", it becomes possible to correct the position of the robot 300 in accordance with more detailed movement types.

By adding the item "weight of load", the position can be corrected when the circumference of the wheels 303 changes depending on the weight of the robot 300. However, the item "weight of loaded object" is applicable when the wheels 303 are elastically deformed. Furthermore, when the wheels 303 are pneumatic tires, addition of the item "wheel air pressure" enables correction when the circumference of the wheels 303 changes depending on the air pressure of the wheels 303. By adding the item "wheel circumference", it becomes possible to correct the case where the circumference of the wheel 303 changes due to wear of the wheel 303.

By adding the item "wheel torque", it becomes possible to make corrections according to the coefficient of friction of the road surface. By adding the items ``temperature'' and ``humidity,'' it becomes possible to make corrections based on the humidity of the road surface.

By adding the item "robot unique ID", it becomes possible to make corrections according to the habits and characteristics of each robot 300.

(2) In the process 504 of FIG. 5 of the first embodiment, in the first embodiment, the DB registration flags for the speed ratio and angular velocity ratio are set to "0" or "1" according to a certain condition during program execution. "You may set it to ``.'' The conditions for dynamically setting the DB registration flag to "1" are described below.

In a distribution warehouse, the robot 300 may be stopped during workers' off-duty hours or during breaks. A possible idea is to update the correction information 702 in the DB 425 by running the robot 300 on the route with the DB registration flag = 1 during a time period in which the robot 300 does not perform transport work.

The Visual SLAM 422 reads a map 421 created in advance, compares the map 421 with a stereo image obtained from the stereo camera 301, and performs self-position estimation.

Specifically, the Visual SLAM 422 extracts image feature points from the stereo image and compares them with feature points in the map 421 (map feature points) to estimate the self-position. At that time, the number of image feature points obtained from the stereo camera 301 and the number of feature points in the map 421 are compared, and if there is a difference of more than a certain number in the number of feature points, it is determined that a change has occurred in the environment, A possible idea is to update the correction information 702 in the DB 425.

On the other hand, it is conceivable to always set the DB registration flag to 1 and continue to register the correction information 702 such as the speed ratio and acceleration ratio in the DB 425 at all times.

(3) Regarding the DB registration flag in process 513, in addition to the speed ratio and angular velocity ratio, store velocity 1 (ν1), angular velocity 1 (ω1), velocity 2 (ν2), and angular velocity 2 (ω2) that can be calculated. It is also possible. As the format of the database, a format that stores document structures such as a key-value store type or JSON type may also be considered. In addition to the rule-based method shown in Example 1, the speed ratio and angular speed ratio are calculated using machine learning and other methods using position information, orientation, and speed (x, y, θ, ν2, ω2) as input. You may.

(4) Actions of the robot 300 for the purpose of notifying the user when performing the self-position correction process 520 shown in FIG. 5 of the first embodiment will be described. This action is executed during the self-position correction process 520, such as immediately after the process 525.

Specifically, when the self-position correction process 520 is executed and the self-position correction process 520 is continued beyond a certain distance, the robot 300 is stopped. Alternatively, while the self-position correction process 520 is being continuously executed, the robot 300 is caused to travel at a slower speed than usual. Alternatively, the robot 300 runs while turning on or blinking the lamps (tail lamp, turn signal 309, etc.) on the body of the robot 300, or speeding up or slowing down the flashing pattern. Alternatively, it is possible to make a sound using the horn 310 or run the vehicle while playing music.

In this manner, in a section where the self-position correction process 520 occurs frequently, the robot 300 generates light or sound, thereby making it possible to notify the robot 300 of the possibility that some kind of abnormality has occurred.

<Conclusion>
As described above, the robot control system of each of the above embodiments can have the following configuration.

(1) A robot (300) control system in which a server (320) having a processor and a memory estimates the position of a mobile robot (300), wherein the mobile robot (300) is configured to control the traveling state of the mobile robot (300). A first sensor unit (stereo camera 301) that acquires first sensing information (stereo image) from the mobile robot (300) and a sensor different from the first sensor unit (301) are used to control the movement of the mobile robot (300). a second sensor unit (encoder 302) that acquires second sensing information (rotation angle of the wheel 303) from the state, and the server (320) acquires second sensing information (rotation angle of the wheel 303) from the first sensing information (stereo image). The mobile robot is obtained from information on the first running state including the obtained first position and the first attitude (θ) at the first position, and the second sensing information (rotation angle of the wheels 303). (300), the second running state information including information on the second velocity (ν2) and second angular velocity (ω2), and the correspondence information (correction information 702) indicating the correspondence between the first An estimated position (corrected self-position) of the mobile robot (300) is calculated based on a storage unit (DB 425) stored in association with the position of the mobile robot (300), information on the first running state, and information on the second running state. and a calculation unit (self-position correction unit 426) capable of adjusting the position based on the first sensing information (stereo image) acquired from the first sensor unit (301). A first position and the first attitude (θ) are calculated, and if an error occurs when calculating the first position, obtain from the second sensing information (rotation angle of the wheel 303). The estimated position (corrected self-position) of the mobile robot (300) is calculated based on the second running state information (velocity 2, angular velocity 2) and the correspondence information (correction information 702). Robot control system.

With the above configuration, an autonomous guided vehicle (mobile robot) can obtain self-position 1 (first position) calculated from the stereo image (first sensing information) of the stereo camera 301 (first sensor unit). Even if it cannot be obtained due to an error, the first position and It becomes possible to restore the self-position (corrected self-position) with equivalent accuracy.

(2) The robot control system according to (1) above, wherein the correspondence information (correction information 702) includes a first velocity (ν1) at the first position (self-position 1) and a second velocity (v1) at the first position (self-position 1). , and the angular velocity ratio (ω1/ω2) of the first angular velocity (ω1) and the second angular velocity (ω2) in the first attitude (θ). A robot control system characterized by:

With the above configuration, velocity 1 (ν1) is calculated from velocity 2 (ν2) acquired from the encoder 302 and the velocity ratio (ν1/ν2) recorded in the correction information 702, and the second angular velocity (ω2) acquired from the encoder 302 is calculated from the velocity ratio (ν1/ν2) recorded in the correction information 702. ) and the angular velocity ratio (ω1/ω2) recorded in the correction information 702, the angular velocity 1 (ω1) can be calculated, and the corrected self-position (self-position 1) can be calculated from the velocity 1 (ν1) and the angular velocity 1 (ω1). It can be calculated. As a result, even if self-position 1 from the stereo image cannot be obtained due to an error, a corrected self-position is calculated based on velocity 2 and angular velocity 2 acquired from the encoder 302, and self-position 1 ( corrected self-position) can be restored.

(3) In the robot control system according to (2) above, the calculation unit (self-position correction unit 426) is configured to have no error and the preset registration information (DB registration flag) is valid (“ 1''), the first velocity (ν1) and the first angular velocity (ω1) are obtained, and the velocity ratio is determined from the second velocity (ν2) and the second angular velocity (ω2). (ν1/ν2) and the angular velocity ratio (ω1/ω2) are calculated, and the second velocity (ν2) is calculated in association with the first position (self-position 1) and the first attitude (θ). and the second angular velocity (ω2), the velocity ratio (ν1/ν2), and the angular velocity ratio (ω1/ω2) are registered in the correspondence information (correction information 702).

With the above configuration, if there is no error in calculating self-position 1 and the DB registration flag is valid, self-position correction unit 426 acquires velocity 1 and angular velocity 1, and obtains velocity 2 (ν2) and angular velocity 2. (ω2), the velocity ratio (ν1/ν2) and the angular velocity ratio (ω1/ω2) are associated with the self-position 1 and the first attitude (θ), and registered in the correspondence information (correction information 702). This can be used to restore self-position 1 when an error occurs. Note that the velocity 1 and the angular velocity 1 may be calculated from the difference between the previous value and the current value of the self-position 1.

(4) In the robot control system according to (2) above, when the error occurs, the calculation unit (self-position correction unit 426) controls the first position of the mobile robot before the error occurs. The correspondence information (correction information 702) is obtained using the information on the position (self-position 1) and the first attitude (θ), the second velocity (ν2), and the second angular velocity (ω2). Search, obtain the speed ratio (ν1/ν2) and angular velocity ratio (ω1/ω2) from the search results, and combine the obtained speed ratio (ν1/ν2) and angular velocity ratio (ω1/ω2) with the second Based on the estimated value of the first velocity (ν1) and the estimated value of the first angular velocity (ω1) from the velocity (ν2) and the second angular velocity (ω2), the position and orientation of the mobile robot are determined. A robot control system characterized by calculating an estimated position and an estimated posture.

With the above configuration, when an error occurs in the calculation of self-position 1, the self-position correction unit 426 searches for correction information 702 using velocity 2 and angular velocity 2 calculated from the self-position 1 and the information of encoder 302, and searches for the correction information 702. Obtain the velocity ratio and angular velocity ratio from . Then, the self-position correction unit 426 calculates velocity 1 from the speed ratio and velocity 2, calculates angular velocity 1 from the angular velocity ratio and angular velocity 2, and calculates self-position 1 from the self-position 1 and the calculated velocity 1 and angular velocity 1. Posture can be calculated.

(5) In the robot control system according to (4) above, when the error occurs, the calculation unit (self-position correction unit 426) corrects the estimated position calculated by the calculation unit (426). and search the correspondence information (correction information 702) using the estimated posture, the second velocity (ν2) at the estimated position, and the second angular velocity (ω2) at the estimated posture, and from the search results A velocity ratio (ν1/ν2) and an angular velocity ratio (ω1/ω2) are obtained, and the obtained velocity ratio (ν1/ν2) and angular velocity ratio (ω1/ω2) are combined with the second velocity (ν2) at the estimated position. ) and the second angular velocity (ω2) in the estimated posture, calculate an estimated value of the first velocity (ν1) at the estimated position and an estimated value of the first angular velocity (ω1) at the estimated posture. and calculating the position and orientation of the mobile robot based on the estimated value of the first velocity (ν1) at the calculated estimated position and the estimated value of the first angular velocity (ω1) at the estimated orientation. A robot control system characterized by:

With the above configuration, if an error continues to occur in the calculation of self-position 1, the self-position correction unit 426 uses the calculated estimated position and estimated orientation to continue to maintain the position and orientation of the mobile robot even if the error continues. can be estimated.

(6) In the robot control system according to (4) above, the calculation unit (self-position correction unit 426), when searching the correspondence information (correction information 702), calculates the first position ( A search is performed using a first key representing the self-position (1), and a second key representing the first attitude (θ), second velocity (ν2), and second angular velocity (ω2) is searched for the search result. A robot control system characterized by further searching using keys.

With the above configuration, the self-position correction unit 426 narrows down the rough search results using the first key using the second search key, thereby preventing the DB search speed from slowing down using a large number of search keys. Can be suppressed.

(7) The robot control system according to (2) above, wherein the correspondence information (correction information 702) includes the first position (self-position 1), the first attitude (θ), A robot control system comprising the speed ratio (v1/v2) and the angular velocity ratio (ω1/ω2).

With the above configuration, the correspondence information (correction information 702) includes the first position (self-position 1), the first attitude (θ), the velocity ratio (ν1/ν2), and the angular velocity ratio (ω1/ω2). can include.

(8) The robot control system according to (7) above, wherein the correspondence information (correction information 702) includes the first position (self-position 1), the first posture (θ), In addition to the speed ratio (ν1/ν2) and the angular velocity ratio (ω1/ω2), date and time, acceleration, angular acceleration, weight of the loaded object, wheel air pressure, wheel circumference, wheel torque, temperature, and humidity. , a mobile robot (300) unique ID.

With the above configuration, the latest correction information 702 can be selectively searched by adding "date and time". By adding "acceleration" and "angular acceleration", it becomes possible to correct the position of the robot 300 in accordance with more detailed movement types. By adding the "weight of the load", the position can be corrected when the circumference of the wheels 303 changes due to the weight of the robot 300. When the wheels 303 are pneumatic tires, addition of "wheel air pressure" enables correction when the circumference of the wheels 303 changes depending on the air pressure of the wheels 303. By adding the "wheel circumference", it is possible to correct the case where the circumference of the wheel 303 changes due to wear of the wheel 303. By adding "wheel torque", it becomes possible to make corrections according to the coefficient of friction of the road surface. By adding "temperature" and "humidity", it is possible to make corrections based on the humidity of the road surface. By adding the "robot unique ID", it becomes possible to make corrections according to the habits and characteristics of each robot 300.

(9) In the robot control system according to (1) above, when the calculation unit (self-position correction unit 426) cannot obtain the first position (self-position 1) due to the error, the calculation unit (self-position correction unit 426) At least one of blinking a lamp (blinker 309) provided on the mobile robot (300), audio output from a horn (310) provided on the mobile robot (300), and deceleration and stopping of the mobile robot (300) is performed during the movement. A robot control system characterized by giving commands to a robot (300).

With the above configuration, if an error occurs in the calculation of self-position 1, the blinker 309 of the robot 300 is blinked, the horn 310 is sounded, or the wheel motor 306 is decelerated or stopped, so that the calculation of self-position 1 is abnormal. It is possible to notify that this has occurred.

Note that the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the embodiments described above are described in detail to explain the present invention in an easy-to-understand manner, and the present invention is not necessarily limited to including all the configurations described. Furthermore, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, addition, deletion, or replacement of other configurations to some of the configurations of each embodiment may be applied singly or in combination.

Further, each of the above-mentioned configurations, functions, processing units, processing means, etc. may be partially or entirely realized in hardware by designing, for example, an integrated circuit. Moreover, each of the above-mentioned configurations, functions, etc. may be realized by software by a processor interpreting and executing a program that realizes each function. Information such as programs, tables, files, etc. that implement each function can be stored in a memory, a recording device such as a hard disk, an SSD, or a recording medium such as an IC card, an SD card, or a DVD.

Further, the control lines and information lines are shown to be necessary for explanation purposes, and not all control lines and information lines are necessarily shown in the product. In reality, almost all components may be considered to be interconnected.

300 Robot 302 Stereo camera 302 Encoder 303 Wheel 421 Map 422 Visual SLAM
423 Velocity 2, angular velocity 2 calculation unit 425 Database 426 Self-position correction unit 702 Correction information

Claims (11)

A robot control system in which a server having a processor and a memory estimates the position of a mobile robot, the system comprising:
The mobile robot is
a first sensor unit that acquires first sensing information from a running state of the mobile robot;
a second sensor unit that has a different sensor from the first sensor unit and acquires second sensing information from the traveling state of the mobile robot;
The server is
information on a first running state including a first position and a first posture at the first position obtained from the first sensing information; and a second running state of the mobile robot obtained from the second sensing information. a storage unit that stores correspondence relationship information indicating a correspondence relationship between information on a second running state including a speed of the vehicle and a second angular velocity in association with the first position;
a calculation unit capable of calculating an estimated position of the mobile robot based on information on the first running state and information on the second running state;
The arithmetic unit is
If the first position and the first orientation are calculated based on the first sensing information acquired from the first sensor unit, and an error occurs when calculating the first position, A robot control system characterized in that an estimated position of the mobile robot is calculated based on second running state information acquired from the second sensing information and the correspondence information. The robot control system according to claim 1,
The correspondence information is
A robot control system comprising: a speed ratio between the first speed and the second speed at the first position; and an angular speed ratio between the first angular speed and the second angular speed at the first posture. . The robot control system according to claim 2,
The arithmetic unit is
If there is no error and the preset registration information is valid, obtain the first velocity and the first angular velocity, and calculate the speed ratio from the first velocity and the second velocity. calculate the angular velocity ratio from the first angular velocity and the second angular velocity, and calculate the second angular velocity and the second angular velocity in association with the first position and the first attitude. A robot control system characterized in that the speed ratio and the angular velocity ratio are registered in the correspondence information. The robot control system according to claim 2,
The arithmetic unit is
When the error occurs, the correspondence relationship is established between the information on the first position and the first posture of the mobile robot before the error occurs, the second velocity, and the second angular velocity. Search for information, obtain a speed ratio and an angular velocity ratio from the search results, and calculate an estimated value of the first velocity from the obtained velocity ratio and angular velocity ratio, the second velocity, and the second angular velocity. An estimated value of the first angular velocity is calculated, and the position and orientation of the mobile robot are estimated based on the calculated estimated value of the first velocity and the estimated value of the first angular velocity. A robot control system characterized by calculating as follows. The robot control system according to claim 4,
The arithmetic unit is
If the error occurs, the correspondence information is calculated between the estimated position and the estimated orientation calculated by the calculation unit, the second velocity at the estimated position, and the second angular velocity at the estimated orientation. , obtain a speed ratio and an angular velocity ratio from the search results, and calculate the estimated position from the obtained speed ratio and angular velocity ratio, the second velocity at the estimated position, and the second angular velocity at the estimated posture. An estimated value of the first velocity at the estimated position and an estimated value of the first angular velocity at the estimated orientation are calculated, and an estimated value of the first velocity at the calculated estimated position and an estimated value of the first angular velocity at the estimated orientation are calculated. 1. A robot control system, wherein the position and orientation of the mobile robot are calculated based on an estimated value of angular velocity. The robot control system according to claim 4,
The arithmetic unit is
When searching for the correspondence relationship information, a search is performed using the first key representing the first position, and the first attitude, the second velocity, and the second A robot control system characterized in that a search is performed using a second key representing angular velocity. The robot control system according to claim 2,
The correspondence information is
A robot control system comprising: the first position, the first posture, the speed ratio, and the angular speed ratio. The robot control system according to claim 7,
The correspondence information is
In addition to the first position, first attitude, speed ratio, and angular velocity ratio, date and time, acceleration, angular acceleration, weight of the loaded object, wheel air pressure, wheel circumference, and wheel torque. , temperature, humidity, and a mobile robot unique ID. The robot control system according to claim 1,
The arithmetic unit is
If the first position cannot be obtained due to the error, at least one of blinking a lamp provided on the mobile robot, outputting a sound from a horn provided on the mobile robot, and decelerating and stopping the mobile robot may be activated during the movement of the mobile robot. A robot control system characterized by giving instructions to a robot. a server having a processor and memory;
A transport system comprising: a mobile robot connected to the server to transport an object;
The mobile robot is
a first sensor unit that acquires first sensing information from a running state of the mobile robot;
a second sensor unit that has a different sensor from the first sensor unit and acquires second sensing information from the traveling state of the mobile robot;
The server is
A first position obtained from the first sensing information, first running state information including a first posture at the first position, and a first position of the mobile robot obtained from the second sensing information. a storage unit that stores correspondence relationship information indicating a correspondence relationship between the second driving state information including the second speed and the second angular velocity in association with the first position;
a calculation unit capable of calculating an estimated position of the mobile robot based on information on the first running state and information on the second running state;
The arithmetic unit is
If the first position and the first orientation are calculated based on the first sensing information acquired from the first sensor unit, and an error occurs when calculating the first position, A transport system characterized in that the estimated position of the mobile robot is calculated based on the second traveling state information acquired from the second sensing information and the correspondence relationship information. A robot control method in which a server having a processor and a memory estimates the position of a mobile robot, the method comprising:
a first step in which the server acquires first sensing information detected by a first sensor unit of the mobile robot;
a second step in which the server acquires second sensing information detected by a second sensor unit different from the first sensor unit of the mobile robot;
The server obtains first driving state information including a first position and a first attitude at the first position obtained from the first sensing information, and the movement obtained from the second sensing information. a third step of storing correspondence relationship information indicating a correspondence relationship between information on a second running state including a second speed and a second angular velocity of the robot in a storage unit in association with the first position; ,
a fourth step in which the server calculates the first position and the first orientation based on first sensing information acquired from the first sensor unit;
If an error occurs when calculating the first position, the server estimates the mobile robot based on the second traveling state information acquired from the second sensing information and the correspondence information. a fifth step of calculating the position;
A robot control method characterized by comprising:

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