CN102540209A - Calibrating algorithm for positioning system of outdoor mobile robot - Google Patents

Abstract

The invention discloses a calibrating algorithm for a positioning system of an outdoor mobile robot. The positioning system comprises a base station for a charging interface, wherein the base station is provided with an electronic control device of the base station, the electronic control device of the base station comprises a first microcontroller, a charging module, a first global positioning system (GPS) module and a first wireless serial communication module, the mobile robot is provided with an electronic control device of the robot, the electronic control device of the robot is provided with a second microcontroller, a second GPS module and a second wireless serial communication module, and the second microcontroller is provided with a calibrating algorithm. The calibrating algorithm is used for obtaining the latitudinal cosine cosNb of the base station in a longitudinal moving distance delta x = delta e*R*cosNb as a constant in subsequent positioning calculation, and the longitudinal moving distance is obtained by adopting a mode of travelling at a fixed distance D through firstly calculating a latitudinal moving distance delta y = delta n*R, so that the latitudinal cosine cosNb of the base station can be obtained.

Description

The calibration algorithm of outdoor mobile robot positioning system

Technical field

The present invention relates to a kind of calibration algorithm of outdoor mobile robot positioning system, belong to the localization for Mobile Robot technical field.

Background technology

General advanced person's the GPS locator meams the most that adopts now of orientation problem for outdoor mobile robot; But well-known, the GPS locator data has comprised the error that is difficult to avoid, comprising systematic error; Time clock correction such as satellite and receiver; Ephemeris error, ionosphere and tropospheric delay error etc. also comprise with the relevant error immediately of receiver itself.Therefore can only reach the bearing accuracy more than 10 meters based on the separate GPS locator data.In order to eliminate above-mentioned error, can adopt the localization method of two GPS, carry out difference to eliminate above-mentioned error through two gps datas, can obtain point-device longitude variable quantity and latitude variable quantity.But need quote the latitude cosine value of mobile robot base station during the displacement on converting longitude and latitude direction into.This parameter is an absolute value, does not pass through difference processing, has than mistake, if directly be incorporated in location Calculation, locator data validity is reduced.

Summary of the invention

The objective of the invention is the latitude cosine parameter that has big measuring error in the positioning system in order to solve the demarcation problem certainly of the two GPS positioning systems of outdoor mobile robot, to find the solution, for accurate Calculation mobile robot's particular location lays the foundation.

The technical solution adopted for the present invention to solve the technical problems is:

The calibration algorithm of outdoor mobile robot positioning system; Described positioning system is included as the base station that the mobile robot provides charging inlet; Described base station is provided with the base station electronic-controlled installation; Described base station electronic-controlled installation comprises first micro controller; The charging module of control charging process, a GPS module that is connected with described first micro controller, the first wireless serial communication module, described mobile robot is provided with the robot electronic-controlled installation; Described robot electronic-controlled installation is provided with second micro controller, the man-machine interface that is connected with described second micro controller, walking module, environment sensing module, task execution module, the 2nd GPS module and the second wireless serial communication module; A described GPS module obtains the base station locator data, and exports to described first micro controller, and described first micro controller sends to the described second wireless serial communication module through the described first wireless serial communication module; Described the 2nd GPS module obtains the robot locator data; And export to described second micro controller; Simultaneously; The described second wireless serial communication module sends the base station locator data that receives to described second micro controller, and described second micro controller is provided with calibration algorithm, and described calibration algorithm may further comprise the steps:

S1: when the position of described mobile robot in described base station, described second micro controller writes down the base station locator data (E that a described GPS module obtains through the described second wireless serial communication module _b, N _b), write down the locator data (E of robot that described the 2nd GPS module obtains simultaneously _r, N _r);

S2: described mobile robot leaves described base station and starts working, and to any direction fixed range D that advances, arrives calibration position, and described the 2nd GPS module obtains the real-time locator data (e of robot _r, n _r), and sending to described second micro controller, described second micro controller receives the real-time base station locator data (e that a described GPS module obtains through the described second wireless serial communication module simultaneously _b, n _b);

S3: described second micro controller is calculated the skew of the described relatively base station of described mobile robot: longitude shifted by delta e=(e _r-E _r)-(e _b-E _b), latitude shifted by delta n=(n _r-N _r)-(n _b-N _b), the warp displacement Δ x=Δ eRcosN of the described relatively base station of described mobile robot _b, parallel displacement Δ y=Δ nR, described R is the mean radius of terrestrial equator, wherein cosN _bBe the latitude cosine of described base station, have big measuring error, need carry out calibration measurements;

S4: described second micro controller is calculated parallel displacement Δ y=Δ the nR=[(n of the described relatively base station of described mobile robot _r-N _r)-(n _b-N _b)] R, further obtain warp displacement

Therefore can be in the hope of the latitude cosine of described base station ${\mathrm{Cos}N}_b=\frac{\mathrm{\Δ\; x}}{\mathrm{\Δ\; e}\·R}=\frac{\sqrt{D^2-{\mathrm{\Δ\; y}}^2}}{[(e_r-E_r)-(e_b-E_b)]\·R}.$

Beneficial effect of the present invention mainly shows: through moving fixed range to any direction, find the solution base station latitude cosine parameter, have easy to operately, calculate easy advantage, applicability is strong.

Description of drawings

Fig. 1 is a system schematic;

Fig. 2 is the theory diagram of base station electronic-controlled installation;

Fig. 3 is the theory diagram of robot electronic-controlled installation;

Fig. 4 is the calibration algorithm process flow diagram.

Embodiment

Below in conjunction with accompanying drawing the present invention is further described.

With reference to Fig. 1-4; The calibration algorithm of outdoor mobile robot positioning system, described positioning system are included as the base station 12 that mobile robot 13 provides charging inlet, described mobile robot 13 mobile working on a large scale; Therefore adopt rechargeable battery as power source; And described base station 12 provides the charging connector of suitable voltage, and when the electric weight of rechargeable battery will exhaust, described mobile robot 13 sought described base station 12 and charges.

Described base station 12 is provided with the base station electronic-controlled installation; Described base station electronic-controlled installation comprises first micro controller 1 that focuses on; The charging module 4 of control charging process, a GPS module 2 that is connected with described first micro controller 1 and the first wireless serial communication module 3.A described GPS module 2 receives the locator data of described base station 12 and sends to described first micro controller 1, and described first micro controller 1 sends to described mobile robot 13 with the base station locator data through the described first wireless serial communication module 3.

Described mobile robot 13 is provided with the robot electronic-controlled installation; Second micro controller 5 that the electronic-controlled installation setting of described robot focuses on, the man-machine interface 8 that is connected with described second micro controller 5, walking module 9, environment sensing module 10, task execution module 11, the 2nd GPS module 6 and the second wireless serial communication module 7.

Described the 2nd GPS module 6 obtains the robot locator data; And export to described second micro controller 5; Simultaneously, the described second wireless serial communication module 7 will receive the base station locator data that the described first wireless serial communication module 3 sends, and send described second micro controller 5 to.

Described second micro controller 5 is provided with calibration algorithm, and described calibration algorithm may further comprise the steps:

S1: when described mobile robot 13 in the position of described base station 12, described second micro controller logical 5 is crossed the described second wireless serial communication module 7, writes down the base station locator data (E that a described GPS module 2 obtains _b, N _b), write down the locator data (E of robot that described the 2nd GPS module 6 obtains simultaneously _r, N _r);

S2: described mobile robot 13 leaves described base station 12 and starts working, and to any direction fixed range D that advances, arrives calibration position, and described the 2nd GPS module 6 obtains the real-time locator data (e of robot _r, n _r), and sending to described second micro controller 5, simultaneously described second micro controller 5 receives the real-time base station locator data (e that a described GPS module 2 obtains through the described second wireless serial communication module 7 _b, n _b);

S3: described second micro controller 5 is calculated the skew of the described relatively base station 12 of described mobile robot 13: longitude shifted by delta e=(e _r-E _r)-(e _b-E _b), latitude shifted by delta n=(n _r-N _r)-(n _b-N _b), the warp displacement Δ x=Δ eRcosN of the described relatively base station 12 of described mobile robot 13 _b, parallel displacement Δ y=Δ nR, described R is the mean radius of terrestrial equator, wherein cosN _bBe the latitude cosine of described base station 12, have big measuring error, need carry out calibration measurements;

S4: described second micro controller 5 is calculated parallel displacement Δ y=Δ the nR=[(n of the described relatively base station 12 of described mobile robot 13 _r-N _r)-(n _b-N _b)] R, further obtain warp displacement

Therefore can be in the hope of the latitude cosine of described base station 12 ${\mathrm{Cos}N}_b=\frac{\mathrm{\Δ\; x}}{\mathrm{\Δ\; e}\·R}=\frac{\sqrt{D^2-{\mathrm{\Δ\; y}}^2}}{[(e_r-E_r)-(e_b-E_b)]\·R}.$

Among the described step S3, the skew of the described relatively base station 12 of described mobile robot 13: longitude shifted by delta e=(e _r-E _r)-(e _b-E _b), latitude shifted by delta n=(n _r-N _r)-(n _b-N _b) through difference processing, error is very little.Therefore, it is operable calculating and obtaining parallel displacement Δ y=Δ nR, but warp displacement Δ x=Δ eRcosN _bFormula in base station latitude N _bBe an absolute value, do not pass through difference processing, error is very big, will improve the precision grade of positioning system through calibration algorithm removal error wherein.

In described step S4, at first calculate parallel displacement Δ y=Δ the nR=[(n of the described relatively base station 12 of described mobile robot 13 _r-N _r)-(n _b-N _b)] R, again according to straight line displacement, calculate warp displacement

Try to achieve the latitude cosine of described base station 12 at last ${\mathrm{Cos}N}_b=\frac{\mathrm{\Δ\; x}}{\mathrm{\Δ\; e}\·R}=\frac{\sqrt{D^2-{\mathrm{\Δ\; y}}^2}}{[(e_r-E_r)-(e_b-E_b)]\·R}.$

In sum, through moving fixed range, adopt difference method to find the solution the variable quantity of mobile robot at longitude and latitude to any direction; And then obtain the displacement of mobile robot on the latitude direction, again according to straight line displacement, calculate the displacement on the warp direction; Find the solution the latitude cosine parameter of base station from direction; This scaling method has easy to operate, calculates easy advantage, and applicability is strong.

Claims (1)

1. the calibration algorithm of outdoor mobile robot positioning system; Described positioning system is included as the base station that the mobile robot provides charging inlet; Described base station is provided with the base station electronic-controlled installation; Described base station electronic-controlled installation comprises first micro controller; The charging module of control charging process, a GPS module that is connected with described first micro controller, the first wireless serial communication module, described mobile robot is provided with the robot electronic-controlled installation; Described robot electronic-controlled installation is provided with second micro controller, the man-machine interface that is connected with described second micro controller, walking module, environment sensing module, task execution module, the 2nd GPS module and the second wireless serial communication module; A described GPS module obtains the base station locator data, and exports to described first micro controller, and described first micro controller sends to the described second wireless serial communication module through the described first wireless serial communication module; Described the 2nd GPS module obtains the robot locator data; And export to described second micro controller; Simultaneously; The described second wireless serial communication module sends the base station locator data that receives to described second micro controller, and it is characterized in that: described second micro controller is provided with calibration algorithm, and described calibration algorithm may further comprise the steps:

S1: when the position of described mobile robot in described base station, described second micro controller writes down the base station locator data (E that a described GPS module obtains through the described second wireless serial communication module _b, N _b), write down the locator data (E of robot that described the 2nd GPS module obtains simultaneously _r, N _r);

S2: described mobile robot leaves described base station and starts working, and to any direction fixed range D that advances, arrives calibration position, and described the 2nd GPS module obtains the real-time locator data (e of robot _r, n _r), and sending to described second micro controller, described second micro controller receives the real-time base station locator data (e that a described GPS module obtains through the described second wireless serial communication module simultaneously _b, n _b);

S3: described second micro controller is calculated the skew of the described relatively base station of described mobile robot: longitude shifted by delta e=(e _r-E _r)-(e _b-E _b), latitude shifted by delta n=(n _r-N _r)-(n _b-N _b), the warp displacement Δ x=Δ eRcosN of the described relatively base station of described mobile robot _b, parallel displacement Δ y=Δ nR, described R is the mean radius of terrestrial equator, wherein cosN _bBe the latitude cosine of described base station, have big measuring error, need carry out calibration measurements;

S4: described second micro controller is calculated parallel displacement Δ y=Δ the nR=[(n of the described relatively base station of described mobile robot _r-N _r)-(n _b-N _b)] R, further obtain warp displacement

Therefore can be in the hope of the latitude cosine of described base station ${\mathrm{Cos}N}_b=\frac{\mathrm{\Δ\; x}}{\mathrm{\Δ\; e}\·R}=\frac{\sqrt{D^2-{\mathrm{\Δ\; y}}^2}}{[(e_r-E_r)-(e_b-E_b)]\·R}.$

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