CN111459192A - Mobile robot dynamic target tracking method based on RFID - Google Patents
Mobile robot dynamic target tracking method based on RFID Download PDFInfo
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Abstract
The invention belongs to the technical field related to RFID application and discloses a mobile robot dynamic target tracking method based on RFID. The method comprises the following steps: (a) two ends of the mobile robot are respectively provided with an RFID antenna, an RFID tag is arranged on the target tag, and the target tag guides the motion track of the mobile robot through the communication between the RFID tag and the RFID antenna; (b) and the target label is connected with the control system, the tracking condition of the target label is established in the control system, when the current state of the mobile robot obtained through measurement meets the tracking condition, the current moving state of the mobile robot is maintained, and otherwise, the control system adjusts the linear velocity and the angular velocity of the mobile robot. By the method, the dynamic target tracking of the robot overcomes the influences of illumination conditions, shelters and dynamic changes of the environment, and has the advantages of good tracking real-time performance, high precision, small calculation amount and low cost.
Description
Technical Field
The invention belongs to the technical field of RFID application, and particularly relates to a mobile robot dynamic target tracking method based on RFID.
Background
Robot target tracking is an indispensable capability of a mobile robot in various application scenes, such as robot-assisted heavy object carrying, disabled person-assisted robots, multi-robot formation and the like. General solutions to the problem of dynamic target tracking based on visual or laser sensors suffer from occlusion and environmental dynamics. The RFID (radio frequency identification) system has the characteristics of unique ID identification, non-line-of-sight communication, low price, low requirement on computer hardware equipment and the like, and has unique advantages for solving the problem of robot dynamic target tracking.
At present, the problem of robot dynamic target tracking is mostly based on a visual sensor and a laser sensor, and the target object needs to be firstly identified and feature extracted, and then the position of the target object is estimated in real time, so that the self motion is adjusted through the estimation of the position. But these methods are computationally expensive and suffer from occlusion, lighting conditions and environmental dynamics.
To avoid these problems, some studies have begun to use RFID technology to address the tracking of dynamic targets. Firstly, a target label is required to be attached to a target object to be tracked, then communication is established between an antenna and the label on a robot, the label position is estimated by means of readability of RFID and an RSSI sensing model through particle filtering and the like, and then local path planning is carried out. Although the tracking method can estimate the position of the dynamic target in advance, the estimation accuracy is low, so that the tracking accuracy of the dynamic target is poor, and the real-time performance is difficult to guarantee.
Disclosure of Invention
Aiming at the defects or the improvement requirements in the prior art, the invention provides a dynamic target tracking method of a mobile robot based on RFID, which comprises the steps of setting an RFID antenna on the mobile robot and setting an RFID tag on a target, and calculating the real-time linear velocity and angular velocity required by the robot to finish a tracking task in real time through a linear velocity adjusting function and an angular velocity adjusting function obtained by phase signal analysis through the communication between the RFID antenna and the RFID tag. In the tracking process, the robot keeps the relative position relation between the robot and the target label all the time by continuously adjusting the motion of the robot. The method has the advantages of good real-time performance, no need of calibration, small calculated amount, no illumination interference, no shielding interference and the like.
To achieve the above object, according to one aspect of the present invention, there is provided an RFID-based mobile robot dynamic target tracking method, comprising the steps of:
(a) for a mobile robot, setting a target tag for guiding the mobile robot to move, wherein two ends of the mobile robot are respectively provided with an RFID antenna, namely a left FRID antenna and a right FRID antenna, the target tag is provided with the RFID tag, and the target tag is used for guiding the moving track of the mobile robot through the communication between the RFID tag and the RFID antennas;
(b) and the target tag is connected with a control system, a tracking condition of the mobile robot is established in the control system, when the current state of the mobile robot obtained through measurement meets the tracking condition, the current moving state of the mobile robot is maintained, and otherwise, the control system adjusts the linear velocity and the angular velocity of the mobile robot through the target tag.
Further preferably, in step (b), the tracking condition is preferably performed according to the following relation:
wherein the content of the first and second substances,
is the linear velocity adjustment function at time t,
is time tThe angular velocity of the object to be measured is adjusted,
is the phase difference at time t for the left RFID antenna,
is the phase difference at time t of the right RFID antenna.
Further preferably, the
And
the phase difference is preferably calculated according to the following relation:
wherein the content of the first and second substances,
is the actual unwrapping phase of the left RFID antenna at time t,
is the actual unwrapping phase of the left RFID antenna at the first instant,
is the actual unwrapping phase of the right RFID antenna at time t,
the actual unwrapped phase measured by the right RFID antenna at the first instant.
Further preferably, the
And
are calculated according to the following relation:
wherein, γ(i)Is the phase, θ, measured at the ith time(i)Is the actual unwrapped phase corresponding to the phase measured at the ith time, t is the arbitrary phase measurement time, and i is the time.
Further preferably, in the step (b), the control system adjusts the linear velocity and the angular velocity of the mobile robot through the target tag, preferably by using a PID control method.
Further preferably, the PID control is preferably performed according to the following relation:
wherein the content of the first and second substances,
is the linear velocity adjustment of the robot at time t,
is the angular velocity adjustment of the robot at time t, P1，I1And D1Respectively, the proportional, integral and differential term coefficients, P, corresponding to the linear velocity adjustment function2，I2And D2Respectively, proportional, integral and differential term coefficients corresponding to the angular velocity adjustment function, m represents the number of recent phase observations used in the integration section,
is the linear velocity of the robot at time t-1,
is the angular velocity of the robot at time t-1.
Further preferably, in step (b), the control system is disposed inside or outside the target tag.
Generally, compared with the prior art, the technical scheme of the invention has the following beneficial effects:
1. the method combines the mobile robot with the RFID system, controls the motion of the robot through signal comparison under the condition of not calculating the phase position relation between the label and the robot, has low requirement on the system, and does not need to calibrate the relative pose relation between the robot and the antenna;
2. according to the RFID servo control algorithm, the label is not required to be positioned, so that the influence of positioning errors caused by directional gain and phase center offset of a phase signal in a resolving position model on a tracking result and the condition of navigation failure caused by positioning estimation failure are avoided, and the calculation load is small compared with that of position estimation;
3. the dynamic target tracking method provided by the invention uses the RFID technology, has good real-time performance and high tracking precision, and is not interfered by factors such as the illumination condition, shielding, dynamic environment change and the like.
Drawings
FIG. 1 is a schematic diagram of a system for implementing an RFID-based mobile robot dynamic target tracking method constructed in accordance with a preferred embodiment of the present invention;
FIG. 2 is a flow chart of a dynamic target tracking method for an RFID-based mobile robot constructed in accordance with a preferred embodiment of the present invention;
fig. 3 is a schematic diagram of a servo control system constructed in accordance with a preferred embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Fig. 1 is a schematic diagram of a mobile robot navigation system for a pre-RFID navigation method according to a preferred embodiment of the present invention, as shown in fig. 1, the present invention installs an RFID system on a mobile robot platform, installs RFID antennas on both sides of a robot, attaches a target RFID tag to a target object, assigns an ID of the target tag to the robot in advance, establishes communication between a reader antenna and the RFID tag, acquires a phase signal in real time, and processes the phase signal using the information to track a dynamic target.
Fig. 2 is a flowchart of a dynamic target tracking method for a mobile robot based on RFID according to an embodiment of the present invention, and as shown in fig. 2, a dynamic target tracking method for a mobile robot based on RFID according to an embodiment of the present invention senses a target object with an RFID tag by using a mobile robot carrying an RFID reader/writer and an RFID antenna, and designs a corresponding servo control algorithm according to phase difference information of the two antennas, so that the robot completes real-time and high-precision target tag tracking without calculating a position of the target tag, and the method specifically includes the following steps:
s1, before performing tracking, the ID of the target tag is assigned to the mobile robot, so that the RFID reader antenna carried by the mobile robot can establish communication with the target tag to acquire phase information. When a target object carrying a target label stops at any initial position in front of the mobile robot, two RFID reader antennae carried by the mobile robot start to acquire real-time phase information, and the process is continued all the time;
s2, performing phase unwrapping processing on the two sets of acquired phase information, and then respectively calculating the phase difference of the phase information received by the left antenna and the right antenna at the current time and the initial time;
in particular, the rootBased on the comparison of the relative relationship between the continuously measured phase values, the relative unwrapping process is performed on the original phase information, at the initial time, the unwrapped phase is equal to the original phase, so that gamma is(i)For the ith phase, measure the phase measured at the corresponding time, let θ(i)Let t be the phase measurement time for the actual unwrapping phase corresponding to the phase measured at the ith phase measurement corresponding time, the specific unwrapping method is performed according to the following formula:
further calculating a phase difference based on the obtained unwrapped phase, where the phase difference is defined as a difference between the phase at the current time t and the phase at the initial time; order to
For the phase difference at time t of the left antenna
Is the phase difference of the right antenna at time t
For the actual unwrapping phase at time t of the left antenna
For the actual unwrapping phase of the right antenna at t times
For the phase of the initial time of the left antenna, order
The phase difference between the two antennas can be calculated for the phase of the right antenna at the initial time
Respectively as follows:
according to the phase difference of the left antenna and the right antenna, a linear velocity adjusting function and an angular velocity adjusting function of the robot are constructed;
let the linear velocity of the robot adjust a function of
Let the angular velocity of the robot adjust a function of
Specifically, the objective function of the control system is
I.e. the movements of the robot are adjusted such that the current phase is kept in agreement with the initial phase.
S3, controlling the robot by using a PID control method, adjusting the linear velocity and the angular velocity of the robot in real time, and keeping the phase difference received by the left antenna and the right antenna of the robot to be 0 in the motion process, so that the relative pose of the robot and the target label is ensured;
fig. 3 is a schematic diagram of a servo control system constructed according to a preferred embodiment of the present invention, as shown in fig. 3, in which a PID control algorithm is used to control linear and angular velocities of a robot, specifically: given value for a PID control system
And
the output of the system is the linear velocity of the robot
And angular velocity
The observed value of the system is
And
P1、I1、D1is a PID control parameter, P, corresponding to the linear velocity modulation function2、I2、D2Is PID control parameter corresponding to angular velocity adjustment function according to servo control system
The linear velocity and the angular velocity of the robot can be obtained by the unified control flow combined with the control rule of the PID algorithm
And then the robot updates the linear velocity and the angular velocity in real time and tracks the motion of the target label.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (7)
1. A mobile robot dynamic target tracking method based on RFID is characterized by comprising the following steps:
(a) for a mobile robot, setting a target tag for guiding the mobile robot to move, wherein two ends of the mobile robot are respectively provided with an RFID antenna, namely a left FRID antenna and a right FRID antenna, the target tag is provided with the RFID tag, and the target tag is used for guiding the moving track of the mobile robot through the communication between the RFID tag and the RFID antennas;
(b) and the target tag is connected with a control system, a tracking condition of the mobile robot is established in the control system, when the current state of the mobile robot obtained through measurement meets the tracking condition, the current moving state of the mobile robot is maintained, and otherwise, the control system adjusts the linear velocity and the angular velocity of the mobile robot through the target tag.
2. An RFID-based mobile robot dynamic target tracking method according to claim 1, wherein in step (b), the tracking condition is preferably performed according to the following relation:
wherein the content of the first and second substances,
is the linear velocity adjustment function at time t,
is an angular velocity adjustment function at time t,
is the phase difference at time t for the left RFID antenna,
is the phase difference at time t of the right RFID antenna.
3. The dynamic target tracking method for mobile robot based on RFID as claimed in claim 2, wherein said method is characterized in that
And
the phase difference is preferably calculated according to the following relation:
wherein the content of the first and second substances,
is the actual unwrapping phase of the left RFID antenna at time t,
is the actual unwrapping phase of the left RFID antenna at the first instant,
is the actual unwrapping phase of the right RFID antenna at time t,
the actual unwrapped phase measured by the right RFID antenna at the first instant.
4. The dynamic target tracking method for mobile robot based on RFID as claimed in claim 3, wherein said method is characterized in that
And
are calculated according to the following relation:
wherein, γ(i)Is the phase, θ, measured at the ith time(i)Is the actual unwrapped phase corresponding to the phase measured at the ith time, t is the arbitrary phase measurement time, and i is the time.
5. The dynamic target tracking method for mobile robot based on RFID as claimed in claim 1, wherein in step (b), the control system adjusts the linear velocity and angular velocity of the mobile robot through the target tag, preferably by using PID control.
6. The dynamic target tracking method for the RFID-based mobile robot as claimed in claim 1, wherein the PID control is preferably performed according to the following relation:
wherein the content of the first and second substances,
is the linear velocity adjustment of the robot at time t,
is the angular velocity adjustment of the robot at time t, P1，I1And D1Respectively, the proportional, integral and differential term coefficients, P, corresponding to the linear velocity adjustment function2，I2And D2Respectively, proportional, integral and differential term coefficients corresponding to the angular velocity adjustment function, m represents the number of recent phase observations used in the integration section,
is the linear velocity of the robot at time t-1,
is the angular velocity of the robot at time t-1.
7. The dynamic target tracking method for mobile robot based on RFID of claim 1, wherein in step (b), the control system is disposed inside or outside the target tag.
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|---|---|---|---|---|
| CN114330384A (en) * | 2021-11-24 | 2022-04-12 | 南京邮电大学 | Passive RFID phase information-based arm motion track tracking method |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050206555A1 (en) * | 2004-03-16 | 2005-09-22 | Raj Bridgelall | Multi-resolution object location system and method |
| US7353089B1 (en) * | 2004-04-13 | 2008-04-01 | P.E.M. Technologies, Llc | Method and system for a signal guided motorized vehicle |
| CN101828307A (en) * | 2007-09-11 | 2010-09-08 | Rf控制有限责任公司 | Radiofrequency signal is obtained and source location system |
| US20100328073A1 (en) * | 2009-06-30 | 2010-12-30 | Intermec Ip Corp. | Method and system to determine the position, orientation, size, and movement of rfid tagged objects |
| CN106997205A (en) * | 2017-04-27 | 2017-08-01 | 西南科技大学 | A kind of system and method for positioning and tracking to target for mobile robot |
| CN108614980A (en) * | 2018-04-16 | 2018-10-02 | 西南科技大学 | A kind of the dynamic object positioning system and method for combining RFID and laser intelligence |
| CN110132273A (en) * | 2019-04-17 | 2019-08-16 | 华中科技大学 | A kind of Mobile Robotics Navigation method based on RFID servo techniques |
| CN110442014A (en) * | 2019-07-30 | 2019-11-12 | 华中科技大学 | A kind of location-based mobile robot RFID servo method |
-
2020
- 2020-03-26 CN CN202010225467.1A patent/CN111459192B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050206555A1 (en) * | 2004-03-16 | 2005-09-22 | Raj Bridgelall | Multi-resolution object location system and method |
| US7353089B1 (en) * | 2004-04-13 | 2008-04-01 | P.E.M. Technologies, Llc | Method and system for a signal guided motorized vehicle |
| CN101828307A (en) * | 2007-09-11 | 2010-09-08 | Rf控制有限责任公司 | Radiofrequency signal is obtained and source location system |
| US20100328073A1 (en) * | 2009-06-30 | 2010-12-30 | Intermec Ip Corp. | Method and system to determine the position, orientation, size, and movement of rfid tagged objects |
| CN106997205A (en) * | 2017-04-27 | 2017-08-01 | 西南科技大学 | A kind of system and method for positioning and tracking to target for mobile robot |
| CN108614980A (en) * | 2018-04-16 | 2018-10-02 | 西南科技大学 | A kind of the dynamic object positioning system and method for combining RFID and laser intelligence |
| CN110132273A (en) * | 2019-04-17 | 2019-08-16 | 华中科技大学 | A kind of Mobile Robotics Navigation method based on RFID servo techniques |
| CN110442014A (en) * | 2019-07-30 | 2019-11-12 | 华中科技大学 | A kind of location-based mobile robot RFID servo method |
Non-Patent Citations (3)
| Title |
|---|
| WU HAIBING 等: "An Efficient RFID-Based Localization Method with Mobile Robot", 《INTELLIGENT ROBOTICS AND APPLICATIONS, ICIRA 2016, PT I》 * |
| 何静 等: "融合RFID相位差和激光扫描的动态目标定位", 《仪器仪表学报》 * |
| 洪超: "基于解缠相位的RFID标签定位算法研究", 《中国优秀硕士学位论文全文数据库 信息科技辑》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114330384A (en) * | 2021-11-24 | 2022-04-12 | 南京邮电大学 | Passive RFID phase information-based arm motion track tracking method |
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