CN217543371U - Indoor positioning system based on ultrasonic ranging - Google Patents
Indoor positioning system based on ultrasonic ranging Download PDFInfo
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- CN217543371U CN217543371U CN202221277636.7U CN202221277636U CN217543371U CN 217543371 U CN217543371 U CN 217543371U CN 202221277636 U CN202221277636 U CN 202221277636U CN 217543371 U CN217543371 U CN 217543371U
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Abstract
An indoor positioning system based on ultrasonic ranging, comprising: the system comprises a fixed base station and a mobile terminal positioning node, wherein the fixed base station is fixedly arranged at the indoor top, and the mobile terminal positioning node is arranged indoors; the fixed base station comprises a first main control MCU which is respectively and electrically connected with a first wireless communication module, a first ultrasonic transmitting and receiving module and a first power supply module and processes data information of each module; the mobile end positioning node comprises a second main control MCU, the second main control MCU is respectively and electrically connected with a second wireless communication module, a second ultrasonic transmitting and receiving module, a steering engine module, an electronic compass module and a second power module, and data information of all the modules is processed to enable the mobile end node to complete positioning; through the technical scheme, the indoor environment is accurately positioned, the system has the advantages of low cost and few blind areas, and is simple in structure and flexible in positioning.
Description
Technical Field
The utility model relates to an indoor location technology field, in particular to indoor positioning system based on ultrasonic ranging.
Background
Outdoor positioning technologies represented by GPS are well established, however, when a user is indoors, because GPS signals need to penetrate through a building, indoor positioning continues to depend on outdoor positioning technologies such as GPS, reliability of positioning results is lost, positioning accuracy is difficult to guarantee, and GPS positioning results are rapidly deteriorated due to multipath effects and signal shielding. Commonly used indoor positioning technologies include UWB technology, wi-Fi technology, bluetooth technology, RFID technology, etc., but most indoor positioning technologies are rather costly in terms of equipment cost. At present, the ultrasonic technology is mature, the production cost of the ultrasonic module is low, and the ultrasonic has the characteristic of good directivity, so that the ultrasonic positioning device is very suitable for being applied to indoor positioning.
Between 1989 and 1992, olivetti laboratories developed one of the earliest indoor positioning systems-the infrared-based Active Badges positioning system, but was not generalized due to the existence of significant drawbacks. Then, an Active Bat system based on ultrasonic waves is designed in AT & T laboratories, positioning can be achieved by processing AT least three groups of data by adopting a TOA algorithm, and errors can be controlled to be about 3-4 cm. Compared with the western countries, the research on the domestic indoor positioning technology is late, the technology is not mature enough, but great progress and innovation are made, and in 2011, wang Junzheng of Beijing university of science and technology, and the like, a conveniently-regulated ultrasonic ranging system is designed by applying a Kalman filtering range adaptive measurement method. In 2013, zhang Yonghong of Nanjing university of information engineering, etc. removed noise from ultrasonic signals.
SUMMERY OF THE UTILITY MODEL
The utility model discloses to not enough among the prior art, provide an indoor positioning system based on ultrasonic ranging, realized the accurate positioning of indoor environment to possess the system superiority of low cost, few blind area, the structure is simple and easy, and the location is nimble.
In order to achieve the above purpose, the utility model adopts the following technical scheme:
an indoor positioning system based on ultrasonic ranging, comprising: the system comprises a fixed base station and a mobile terminal positioning node, wherein the fixed base station is fixedly arranged at the indoor top, and the mobile terminal positioning node is arranged indoors;
the fixed base station comprises a first main control MCU, the first main control MCU is respectively and electrically connected with a first wireless communication module, a first ultrasonic transmitting and receiving module and a first power supply module, and data information of each module is processed;
the mobile terminal positioning node comprises a second main control MCU, the second main control MCU is electrically connected with a second wireless communication module, a second ultrasonic wave transmitting and receiving module, a steering engine module, an electronic compass module and a second power module respectively, and data information of each module is processed to enable the mobile terminal node to complete positioning;
the first wireless communication module is in communication connection with the second wireless communication module, so that the mobile terminal positioning node is matched with the fixed base station when in positioning requirement; the second ultrasonic transmitting and receiving module is arranged on the steering engine, so that the second ultrasonic transmitting and receiving module transmits ultrasonic waves to different directions through the steering of the steering engine; the second ultrasonic transmitting and receiving module is connected with the first ultrasonic transmitting and receiving module through ultrasonic communication to realize ranging; the electronic compass module is used for acquiring direction information.
In order to optimize the technical scheme, the specific measures adopted further comprise:
furthermore, the mobile terminal positioning node further comprises a temperature sensor, and the temperature sensor is electrically connected with the second main control MCU.
Furthermore, the mobile terminal positioning node further comprises a WIFI communication module, the WIFI communication module is in telecommunication connection with the second main control MCU, and the WIFI communication module is in communication connection with the PC terminal.
Furthermore, the frequency of the first ultrasonic wave transmitting and receiving module and the frequency of the second ultrasonic wave transmitting and receiving module are both 40KHZ.
The beneficial effects of the utility model are that: this application is through steering wheel and second ultrasonic wave transmission and receiving module's combination to obtain the distance and the direction information of removal end location node in the space with the help of electronic compass module simultaneously, greatly reduced positioning system's location blind area, compare with current multiple spot location, this system is still less to the reliance of basic station. Most of the modules adopted by the system are conventional, so that the construction and operation cost of the whole system is very low. Therefore, the system has the advantages of simple structure, flexible positioning and low requirement on technology in the construction aspect.
Drawings
Fig. 1 is the utility model discloses fixed base station divides position distribution schematic with removal end location node.
Fig. 2 is a schematic diagram of the connection relationship between the modules of the fixed base station of the present invention.
Fig. 3 is the schematic diagram of the connection relationship between the modules of the mobile terminal positioning node of the present invention.
Fig. 4 is a schematic view of the connection relationship of the steering engine of the present invention.
Fig. 5 is a schematic diagram of the position location relationship between the mobile terminal location node a and the fixed base station B in the embodiment of the present invention.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings.
The main technical scheme of the application is as follows:
an indoor positioning system based on ultrasonic ranging, comprising: the system comprises a fixed base station and a mobile terminal positioning node, wherein the fixed base station is fixedly arranged at the indoor top, and the mobile terminal positioning node is arranged indoors;
the fixed base station comprises a first main control MCU, the first main control MCU is respectively and electrically connected with the first wireless communication module, the first ultrasonic transmitting and receiving module and the first power supply module, and data information of each module is processed;
the mobile end positioning node comprises a second main control MCU, the second main control MCU is respectively and electrically connected with a second wireless communication module, a second ultrasonic transmitting and receiving module, a steering engine module, an electronic compass module and a second power module, and data information of all the modules is processed to enable the mobile end node to complete positioning;
the first wireless communication module is in communication connection with the second wireless communication module, so that the mobile terminal positioning node is matched with the fixed base station when the positioning is required; the second ultrasonic transmitting and receiving module is arranged on the steering engine, so that the second ultrasonic transmitting and receiving module transmits ultrasonic waves to different directions through the steering of the steering engine; the second ultrasonic transmitting and receiving module is in communication connection with the first ultrasonic transmitting and receiving module to realize ranging; the electronic compass module is used for acquiring direction information.
Furthermore, the mobile terminal positioning node also comprises a temperature sensor, and the temperature sensor is electrically connected with the second master control MCU; so that the second MCU corrects the distance detected between the first and second ultrasonic transmitting and receiving modules according to the temperature information (for example, taking the room temperature as a boundary, increasing the measured distance by 1 cm every time increasing one degree centigrade, and decreasing the measured distance by 1 cm every time decreasing one degree centigrade)
Furthermore, the mobile terminal positioning node further comprises a WIFI communication module, the WIFI communication module is in telecommunication connection with the second main control MCU, and the WIFI communication module is in communication connection with the PC terminal and is used for transmitting data information in the second main control MCU to the PC terminal.
Further, the frequency of the first ultrasonic wave transmitting and receiving module and the second ultrasonic wave transmitting and receiving module is 40KHZ.
Furthermore, the mobile terminal positioning node also comprises a third ultrasonic transmitting and receiving module which is connected with a third ultrasonic transmitting and receiving module of another mobile terminal positioning node through ultrasonic communication, so that the distance between the mobile terminal positioning nodes is measured;
and second wireless communication modules of the mobile terminal positioning nodes are in communication connection with each other so as to realize second main control MCU data interaction between the mobile terminal positioning nodes and each other.
Further, the frequency of the third ultrasonic transmitting and receiving module is 80KHZ.
The specific embodiment of the system of the present application is as follows:
refer to fig. 1-3. The fixed base station is composed of the following contents: the system comprises a LORA wireless communication module (a first wireless communication module), a 40kHz ultrasonic receiving module, a 40kHz ultrasonic transmitting module (a first ultrasonic transmitting and receiving module formed by combining receiving and transmitting), a first power supply module and a singlechip-first main control MCU. The 40kHz ultrasonic transmitting and receiving module is used for conventional positioning service, and the LORA is responsible for communicating with the mobile node and receiving a positioning instruction from the mobile node.
Refer to fig. 1-3. The mobile end node is comprised of: the electronic compass module, the steering wheel rotates, 80kHz ultrasonic wave emission module, 40kHz ultrasonic wave emission module, 80kHz ultrasonic wave receiving module, 40kHz ultrasonic wave receiving module (wherein, 40 kHz's transmission and receiving make up into second ultrasonic wave transmission and receiving module, 80 kHz's transmission and receiving make up into third ultrasonic wave transmission and receiving module), LORA wireless communication module (second wireless communication module, be responsible for and fixed base station between the communication), wiFi communication module (be responsible for gathering the positioning data and send to the PC end), a temperature sensor, second power module, singlechip-second master control MCU. Wherein, the 40kHz ultrasonic receiving and transmitting module is responsible for participating in a conventional positioning mode. The electronic compass can mark the orientation of the node and participate in the determination of the direction by combining with the steering engine. The 80kHz ultrasonic transmitting and receiving module is responsible for participating in the partner positioning mode. The LORA module is responsible for communicating with fixed base stations and other mobile nodes. The temperature sensor is responsible for participating in ranging correction. And the Wi-Fi module is responsible for uploading the positioning information to the server.
And (3) a conventional positioning mode: any mobile terminal positioning node within the range of four fixed base stations can adopt a conventional positioning mode. In a normal positioning mode, a mobile terminal positioning node sends a positioning request, the request is sent to a fixed base station through an LORA module, each request carries the number of the fixed positioning base station possibly nearby, and the fixed positioning base station node is appointed to enter a waiting state. Wherein, each fixed base station and each mobile terminal positioning node are assigned with unique numbers. And the fixed base station immediately enters a waiting state after receiving the instruction through the LORA module of the fixed base station, so that the fixed base station and the mobile terminal positioning node are matched.
Refer to fig. 4-5. After matching is completed, the mobile end positioning node searches for a fixed base station through the matching of the steering engine and the second ultrasonic transmitting and receiving module so as to realize positioning. The method specifically comprises the following steps: after a steering engine on the mobile end positioning node rotates by an angle each time, an ultrasonic signal is sent by the second ultrasonic transmitting and receiving module, an overtime time is waited, when the overtime time still does not receive the response of the fixed base station, the fixed base station is not positioned in the direction pointed by the current steering engine, the fixed base station continues to rotate by an angle, the rotating angle is the included angle of the ultrasonic wave transmitted by the ultrasonic transmitting module (the ultrasonic wave transmitted by the second ultrasonic transmitting and receiving module is a wide-angle range, and the rotating angle of the steering engine is also the wide angle), then the last operation is repeated, and the ultrasonic signal is continuously sent and waited. After the mobile node transmits an ultrasonic signal and receives a response of the ultrasonic module of the fixed base station in a timeout period, the waiting time in the middle is measured, the distance between the mobile node and the fixed base station can be obtained by correcting the ultrasonic ranging according to the ambient temperature at the time, the direction of the mobile node where the fixed node is located can be obtained according to the rotating angle of the steering engine and the pointing direction of the electronic compass at the time (for example, the steering engine rotates clockwise one angle at each time by taking the true south pointed by the electronic compass as the starting direction, so that the detection direction of the ultrasonic wave relative to the true south is known when the ultrasonic signal returns), then the next base station nearby is designated, and the distance and the direction are measured by repeating the complete ranging process. If the steering engine does not respond to the ultrasonic wave after rotating for 360 degrees, the appointed fixed base station is not in the effective ranging range, and then the fixed base station is skipped over and the next fixed base station is appointed continuously; the position of the mobile terminal positioning node is determined through two or more fixed base stations.
It is further supplemented that the position search of the mobile terminal positioning node by only one fixed base station is not accurate, so that a better positioning result can be obtained by a plurality of fixed base stations. The method specifically comprises the following steps: refer to fig. 5. According to the above content, the steering engine can rotate clockwise by an angle every time by taking the true south pointed by the electronic compass as the starting direction, so that the detection direction of the ultrasonic wave relative to the true south is known when an ultrasonic signal returns. In the embodiment of fig. 5, the return signal is found just in the initial south-plus direction. At this time, since the position of the fixed base station is fixed and the distance from the mobile-end location node to the fixed base station is known from the ultrasonic ranging, it can be known that the mobile-end location node is necessarily on the circle in fig. 5 (the diameter of the circle in the figure is the detected distance). In combination with the detection direction of the ultrasonic wave (in this embodiment, the true south), and the detection wide angle of the ultrasonic wave, it can be known that the two extreme positions (e.g., A1 and A2 in fig. 5) of the mobile-end location node are located, that is, the mobile-end location node is necessarily located on the minor arc between A1 or A2 or A1 and A2, because the return signal can be obtained only at these positions. And then another matched fixed base station is positioned in the same way, and the intersection point between the two matched fixed base stations is the position of the positioning node of the mobile terminal. Thereby enabling the location of the mobile node to be determined from the location of the fixed base station.
In fig. 5, α is a transmission included angle of the ultrasonic wave transmitting module of the mobile terminal positioning node, B in fig. 5 is a position where the fixed base station is located, a is on a minor arc between A1 and A2, a is not marked in the figure, and α can be also equal to α according to the geometric knowledge that ═ A1BA 2. After the mobile node a and a fixed base station B complete a distance measurement and a direction measurement, it can be known that a is located on the inferior arc between A1 and A2, and after the mobile node and two fixed nodes complete the distance and direction measurement, the possible location is the intersection point of the two inferior arcs. Or ranging with four nearby fixed base stations, and completing positioning by a four-point positioning method. It should be appreciated that the positioning is accomplished in more than one way, as long as the positioning is accomplished based on the distance and direction information that has been measured. In the conventional mode, the mobile node can know the distance and the direction between the mobile node and the base station, and can know the orientation of the mobile node by using the electronic compass, so that less base stations can be used for completing positioning by integrating the information, and the dead zone of positioning is greatly reduced.
The present application also provides a buddy location mode other than the conventional location mode, which requires the use of a third ultrasound transmitting and receiving module. In the conventional positioning mode described above, if there are insufficient nearby available positioning base stations, the buddy positioning mode may be initiated to further narrow the area in which the target mobile node is located by means of other mobile nodes whose nearby known locations are located. In the buddy mode, due to the lack of nearby fixed base stations, other mobile nodes with known locations within the ranging range may participate in assisted positioning, referred to as assisted positioning nodes. Partner positioning cannot be completed when other auxiliary positioning nodes do not exist nearby. When one complete conventional positioning can not be completed, a target mobile node activates a partner positioning mode, under the mode, firstly, the target mobile node finishes interaction with a nearby positionable fixed base station, the target mobile node further sends a request to other mobile nodes possibly nearby through LORA, after the request is sent, the steering engine rotates for one time through an angle of 80kHz ultrasonic transmitting/receiving module (a third ultrasonic transmitting and receiving module), the ultrasonic wave is transmitted once, the angle of the steering engine is the angle covered by the transmitting of the 80kHz ultrasonic transmitting/receiving module, after the ultrasonic wave is transmitted, the target mobile node waits for an overtime period, when the overtime is waited, the auxiliary positioning node is not in the direction pointed by the current steering engine, the steering engine continues to rotate, then the ultrasonic wave is transmitted and waits, and the steps are repeated, when the steering engine rotates for 360 degrees and still does not receive a response, the auxiliary positioning node is not nearby, and the next auxiliary positioning node is continuously appointed. If the position of the designated assistant positioning node is unknown, the assistant positioning node responds negatively, and the target mobile node skips the node. After completing the request and location of other mobile nodes in the vicinity, the target mobile node may attempt location again based on known information. In this mode, the positioning blind area of the mobile node is dynamically changed, but always smaller than that in the conventional positioning mode, which is the supplementary effect of this mode on the conventional positioning mode.
The installation mode of the 80kHz ultrasonic receiving/transmitting module is horizontal installation, and the purpose is to position a service for a partner; the 40kHz ultrasonic receiving/transmitting module is installed in an oblique upward direction in order to serve a normal positioning mode, as far as possible aligned with the receiving module of the fixed base station.
It should be noted that, in the present invention, the terms "upper", "lower", "left", "right", "front", "back", etc. are used for the sake of clarity only, and are not used to limit the scope of the present invention, and the relative relationship changes or adjustments may be made without substantial technical changes.
Above only the utility model discloses an it is preferred embodiment, the utility model discloses a scope of protection not only limits in above-mentioned embodiment, and the all belongs to the utility model discloses a technical scheme under the thinking all belongs to the utility model discloses a scope of protection. It should be noted that, for those skilled in the art, a plurality of modifications and decorations without departing from the principle of the present invention should be considered as the protection scope of the present invention.
Claims (4)
1. An indoor positioning system based on ultrasonic ranging, comprising: the system comprises a fixed base station and a mobile terminal positioning node, wherein the fixed base station is fixedly arranged at the indoor top, and the mobile terminal positioning node is arranged indoors;
the fixed base station comprises a first main control MCU which is respectively and electrically connected with a first wireless communication module, a first ultrasonic transmitting and receiving module and a first power supply module and processes data information of each module;
the mobile terminal positioning node comprises a second main control MCU, the second main control MCU is electrically connected with a second wireless communication module, a second ultrasonic wave transmitting and receiving module, a steering engine module, an electronic compass module and a second power module respectively, and data information of each module is processed to enable the mobile terminal node to complete positioning;
the first wireless communication module is in communication connection with the second wireless communication module, so that the mobile terminal positioning node is matched with the fixed base station when the positioning is required; the second ultrasonic transmitting and receiving module is arranged on the steering engine, so that the second ultrasonic transmitting and receiving module transmits ultrasonic waves to different directions through the steering of the steering engine; the second ultrasonic transmitting and receiving module is connected with the first ultrasonic transmitting and receiving module through ultrasonic communication to realize ranging; the electronic compass module is used for acquiring direction information.
2. The indoor positioning system based on ultrasonic ranging of claim 1, wherein the mobile terminal positioning node further comprises a temperature sensor, and the temperature sensor is electrically connected to the second main control MCU.
3. The indoor positioning system based on ultrasonic ranging of claim 1, wherein the mobile terminal positioning node further comprises a WIFI communication module, the WIFI communication module is in telecommunication connection with the second main control MCU, and the WIFI communication module is in communication connection with the PC terminal.
4. The indoor positioning system based on ultrasonic ranging of claim 1, wherein the first ultrasonic transmitting and receiving module and the second ultrasonic transmitting and receiving module have a frequency of 40KHZ.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202221277636.7U CN217543371U (en) | 2022-05-26 | 2022-05-26 | Indoor positioning system based on ultrasonic ranging |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202221277636.7U CN217543371U (en) | 2022-05-26 | 2022-05-26 | Indoor positioning system based on ultrasonic ranging |
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Assignee: Nanjing Zhishang Xinding Kede Technology Group Co.,Ltd. Assignor: NANJING INSTITUTE OF TECHNOLOGY Contract record no.: X2024980002733 Denomination of utility model: An indoor positioning system based on ultrasonic ranging Granted publication date: 20221004 License type: Common License Record date: 20240312 |