CN108120435A - A kind of plant area's alignment system and localization method based on visible ray - Google Patents

Abstract

The plant area positioning system and positioning method based on visible light provided by the present invention use the PWM coding method, so that the LED lamps do not affect their lighting requirements while sending ID information; in terms of modulation, the main controller is used to modulate the ID information of the lamps , and through the LED driving circuit, the light emitted by the LED lamp contains the ID information of the LED lamp. The built-in camera of the smart phone is used to collect the visible light emitted by the LED lamp, and the characteristics of the image sensor are used to obtain the light information, and the light and dark stripe information of the LED light is scanned into the smart phone line by line. In terms of decoding, digital image processing technology is used to process the acquired light and dark stripes to obtain the binary information contained in the light and dark stripes, which is finally converted into 8-digit hexadecimal digital information; The optimized algorithm performs positioning modeling and data calculation, and realizes indoor precise positioning.

Description

A factory area positioning system and positioning method based on visible light

technical field

The invention relates to a plant area positioning system and positioning method based on visible light, belonging to the technical field of positioning.

Background technique

At present, the positioning problem in the plant area of petrochemical enterprises has been highly concerned, and the industry has designed and produced some equipment for positioning in the plant area. However, the existing positioning technology in the factory area mainly uses radio wave positioning technology, while the indoor positioning technology that is still under development mostly uses wireless local area network or radio wave for positioning. In actual operation, positioning radio waves are easily interfered by other radio signals and weakened by walls, resulting in low positioning accuracy, high power consumption, and high cost, so further research is needed.

Contents of the invention

In order to solve the deficiencies of the prior art, the object of the present invention is to provide a plant area positioning system and positioning method based on visible light. This positioning system adopts the indoor positioning technology based on LED white light. In the case of high precision, make full use of the LED white light in the factory area, the indoor positioning has no electromagnetic pollution, and the deployment is easy, which not only meets the lighting requirements, but also reduces power consumption and cost. At the same time, it will not be interfered by radio, etc. These advantages well make up for the shortcomings and deficiencies of other indoor positioning methods. With the development of next-generation green LED lighting technology, the indoor positioning scheme based on visible light will be a promising indoor positioning scheme.

In order to achieve the above object, the present invention adopts the following technical solutions:

A plant positioning system based on visible light is characterized in that it includes a visible light emitting unit, a smart phone and a location server,

The visible light emitting unit loads the ID information of the LED lamp to be transmitted into the light and dark changes of the LED lamp;

The smart phone receives and decodes the ID information contained in the light of the LED lamp that changes in brightness and darkness, analyzes and obtains the unique identification ID information sent by the LED lamp, uses the built-in spirit level of the smart phone to obtain the horizontal and vertical tilt information of the smart phone, and uses the built-in The gyroscope obtains the geomagnetic declination information of the smart phone, obtains the distance information between the smart phone and the lamp through the size of the lamp image, and the smart phone uploads the ID information to the location server;

The location server, in which the map database returns the location coordinates in the factory area, uses the parameter information acquired by the smart phone to determine the corresponding position in the map database, and displays and updates in real time on the smart phone, thereby completing the positioning.

The aforementioned visible light-based factory area positioning system is characterized in that the visible light emitting unit includes a master controller based on STM32, an LED light source and an LED driving circuit.

The aforementioned visible light-based factory positioning system is characterized in that the LED light source uses a 3W high-power white LED as the signal source, and its rated parameters are 9V and 330mA.

The aforesaid plant location system based on visible light is characterized in that the transmission information generated by the LED drive circuit through the STM32-based main controller code is used as the input of the drive circuit, and the input signal is amplified while giving a bias to ensure The LED light source works normally, and the LED drive circuit realizes the change of the output by adjusting the variable resistance value according to the characteristics of the LED light source used.

The aforementioned visible light-based factory positioning system is characterized in that a spirit level and a gyroscope are arranged in the smart phone.

The aforementioned positioning method of a factory area positioning system based on visible light is characterized in that it includes the following steps,

Step (A), the visible light emitting unit loads the ID information of the LED lamp to be transmitted into the light and dark changes of the LED light;

Step (B), use the camera of the smart phone as the terminal to receive the ID information to receive and decode the ID information contained in the lights of the LED lamps that change in brightness and darkness, analyze and obtain the unique identification ID information sent by the LED lamps, and use the built-in level of the smart phone to obtain The horizontal and vertical tilt information of the smart phone, the geomagnetic declination information of the smart phone is obtained by using the built-in gyroscope, the distance information between the smart phone and the lamp is obtained through the size of the lamp image, and the smart phone uploads the ID information to the location server;

Step (C), the map database of the location server returns the location coordinates in the factory area, uses the parameter information obtained by the smartphone to determine the corresponding location in the map database, and displays and updates it in real time on the smartphone to complete the positioning.

The beneficial effects achieved by the present invention: the visible light-based plant positioning system and positioning method provided by the present invention use the PWM coding method, so that the LED lamps do not affect their lighting requirements while sending ID information; in terms of modulation, the main control The device modulates the ID information of the lamp, and through the LED driving circuit, the light emitted by the LED lamp contains the ID information of the LED lamp. The built-in camera of the smart phone is used to collect the visible light emitted by the LED lamp, instead of the traditional receiving antenna to receive radio information, and the characteristics of the image sensor are used to obtain the light information, and the light and dark stripe information of the LED light is scanned into the smart phone line by line. In terms of decoding, the traditional radio wave decoding method is not adopted, but digital image processing technology is used to process the obtained light and dark stripes to obtain the binary information contained in the light and dark stripes, and finally convert them into 8-digit hexadecimal numbers. Information; combined with comprehensive parameters such as the level of the smartphone, positioning modeling and data calculation are carried out through optimized algorithms to achieve accurate indoor positioning.

Description of drawings

Fig. 1 is a functional block diagram of the positioning method of the plant area positioning system based on visible light according to the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings. The following examples are only used to illustrate the technical solution of the present invention more clearly, but not to limit the protection scope of the present invention.

A plant area positioning system based on visible light, including a visible light emitting unit, a smart phone and a location server,

The visible light emitting unit loads the ID information of the LED lamp to be transmitted into the light and dark changes of the LED lamp;

The smart phone receives and decodes the ID information contained in the light of the LED lamp that changes in brightness and darkness, analyzes and obtains the unique identification ID information sent by the LED lamp, uses the built-in spirit level of the smart phone to obtain the horizontal and vertical tilt information of the smart phone, and uses the built-in The gyroscope obtains the geomagnetic declination information of the smart phone, obtains the distance information between the smart phone and the lamp through the size of the lamp image, and the smart phone uploads the ID information to the location server;

The location server, in which the map database returns the location coordinates in the factory area, uses the parameter information acquired by the smart phone to determine the corresponding position in the map database, and displays and updates in real time on the smart phone, thereby completing the positioning.

Further, the visible light emitting unit includes a main controller based on STM32, an LED light source and an LED driving circuit. The LED light source uses a 3W high-power white light LED as the signal source, and its rated parameters are 9V and 330mA. The 300mA is used as the DC bias point. The reason is that within the maximum operating current range, the power of the LED light source has a linear relationship with the current, and the light source has good modulation characteristics. The transmission information generated by the LED drive circuit based on the STM32-based main controller code is used as the input of the drive circuit, and the input signal is amplified while giving a bias to ensure the normal operation of the LED light source. The LED drive circuit is based on the LED light source used. The output can be changed by adjusting the variable resistance value, and it can be flexibly adjusted according to the light source parameters in the actual application. In addition to providing a large enough current to ensure the normal operation of the white light, the LED drive circuit must also provide suitable static operation. point, so that the light source can output sufficient power and have good linearity, and ensure that the signal can be output linearly after modulation.

Further, described spirit level, gyroscope adopt Apple computer iMac as development hardware, take IOS system as development environment, system version is above X EI Capitan, and development tool is Xcode 7.31.

A positioning method of a factory area positioning system based on visible light, comprising the following steps,

Step (A), the visible light emitting unit loads the ID information of the LED lamp to be transmitted into the light and dark changes of the LED light;

Step (B), use the camera of the smart phone as the terminal to receive the ID information to receive and decode the ID information contained in the lights of the LED lamps that change in brightness and darkness, analyze and obtain the unique identification ID information sent by the LED lamps, and use the built-in level of the smart phone to obtain The horizontal and vertical tilt information of the smart phone, the geomagnetic declination information of the smart phone is obtained by using the built-in gyroscope, the distance information between the smart phone and the lamp is obtained through the size of the lamp image, and the smart phone uploads the ID information to the location server;

Step (C), the map database of the location server returns the location coordinates in the factory area, uses the parameter information obtained by the smartphone to determine the corresponding location in the map database, and displays and updates it in real time on the smartphone to complete the positioning.

In the positioning method of this positioning system, the format of data transmission includes: start port, address code, address inverse code, instruction code, instruction inverse code and end code. The start terminal is composed of a continuous 235μs high and low level, and the end code is composed of a 150μs low level. The address code, address inverse code, instruction code and instruction inverse code are all in 8-bit data format, and are sent in the order of low-order first and high-order. Adding address inverse code and instruction inverse code is to improve the accuracy and accuracy of information transmission. reliability. During the process of cyclically sending the position ID information of the LED light source, the system sends high level to the LED light source in idle time slots, so as to ensure that the LED light source can provide lighting services normally. Usually the transmission of a logic 1 is set to 112μs (28μs high level and 84μs low level), and the transmission of a logic 0 is set to 56μs (28μs high level and 28μs low level). In order to avoid confusion in the positioning area where the target to be measured receives position information from multiple signal sources at the same time, the system transmits signals to multiple LED light sources in time-sharing at the transmitting end. When the frequency of the transmitted signal is greater than 60Hz , white LED will not appear obvious flicker phenomenon, human eyes can not distinguish, but if there is continuous logic 1 or continuous logic 0, it will lead to changes in the brightness of the LED light source, affecting the lighting effect. Therefore, using the above encoding method in the system can ensure that each bit in the sequence is composed of two changing pulses, which can effectively reduce the impact of the LED light source on the lighting when sending position ID information. In the system, through the main controller of STM32, the LED lamps are controlled to emit light and dark stripes, and the ID information on the LED lamps is sent out.

This system uses related programs programmed in STM32 to execute. In order not to affect the lighting efficiency of the luminaire when sending the code, and to ensure that it will not flicker due to uneven brightness and darkness, a special coding method is adopted. In this encoding method, a dark stripe with a time interval T and a bright stripe with a time interval T are regarded as 0, and a bright stripe with a time interval T and a dark stripe with a time interval T are regarded as 0. . In this way, whether 0 or 1 is sent, the luminous efficiency of the lamp can be kept at 50%, which avoids flickering and affecting lighting due to different luminous quantities per unit time when sending codes. At the same time, add terminal information to the head of the address code to determine the starting position of the address code, and then use 8-digit hexadecimal numbers to represent the ID of the lamp, with fast transmission speed and high efficiency.

In communication, in order to transmit the digital signal in the high-frequency channel with limited bandwidth, it is necessary to carry out carrier modulation on the digital signal. What this system utilizes is binary on-off keying modulation. Binary ON/OFF keying uses a unipolar non-return-to-zero code sequence to control the ON/OFF of the sinusoidal carrier. Setting one amplitude to 0 and the other to non-zero can allow the receiving end to receive and decode better. In addition, in order to complete the transmission of light information without affecting the lighting, the LED lamps cannot be flickered. Therefore, the modulation method is not only simple OOK modulation, but also needs to load the PWM signal to the LED driver. LED lighting lamps Visible light signals are emitted under normal lighting conditions, allowing smartphone cameras to receive light signals for positioning within the factory.

Since LED lamps can respond quickly to changes in driving voltage or current, the characteristics of the image sensor to read image information row by row in time division are used to modulate the driving current or driving voltage of the light source, to be precise, by changing The frequency and duration of high and low levels in the driving current or driving voltage form different light and dark stripes on the image output by the image sensor. Then, according to the principle of digital image processing, the number or phase of bright or dark fringes in the image is detected, and the frequency information loaded in the driving current is obtained through calculation. The transmitted code is then determined from the frequency information. Finally, the transmitted information is recovered according to a specific decoding method. In this system, the image sensor adopted by the smartphone is a CMOS sensor. Image sensor read row pixels are reset in order, starting from the top, and read row by row until the bottom.

Decoding is the reverse process of encoding. Using the working principle of the camera, the light and dark stripe pictures of light and dark changes are taken by smart phones, combined with digital image processing technology, the light and dark stripes in the light pictures are processed and recognized, and converted into corresponding binary data. Then convert the binary data according to the decompilation method of the coding rules to obtain the eight-digit hexadecimal ID information sent by the LED lamp.

Using the built-in spirit level and gyroscope in the smart phone, you can accurately obtain the horizontal and vertical tilt angles of the smart phone. At the same time, combined with the size relationship of the light image taken by the smart phone, combined with the horizontal and tilt angle information, using the APP built-in solution model, The distance between the light and the user can be calculated, that is, it can be determined that the user is located on a circle at a certain distance from the light. Using the compass information built into the smartphone, the user's geomagnetic declination and other azimuth information can be obtained.

After the smart phone is started, use the terminal camera to obtain the ID information of the lamp, and use the built-in MCU to decode and obtain the ID information of the lamp, so that it can be determined that the user is located near the lamp with the ID. At the same time, according to the size relationship of the photographed lamp images, the corresponding parameters are obtained by using the built-in level meter, gyroscope and compass of the smart phone. Model, combined with the distance information of users and lamps, can comprehensively calculate accurate position information. Match the location information with the cloud or the built-in map library of the smart phone, display the location coordinates, and re-obtain the lamp information from the terminal camera, combined with the real-time updated sensor information, update and display the location information on the map in real time, thus completing Positioning of personnel in the plant area.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the present invention, some improvements and modifications can also be made. It should also be regarded as the protection scope of the present invention.

Claims (6)

1. a kind of plant area's alignment system based on visible ray, it is characterized in that, including VISIBLE LIGHT EMISSION unit, smart mobile phone and position Server,

The VISIBLE LIGHT EMISSION unit, it would be desirable to which the LED lamp id information of transmission is loaded into the light and shade variation of LED lamplight；

The smart mobile phone, receives the id information that the light of LED lamp light and shade variation includes and decoding, parsing obtain LED lamp The unique identities identification id information of transmission obtains the horizontal and vertical tilt of smart mobile phone using the level meter built in smart mobile phone Information obtains the geomagnetic declination information of smart mobile phone using built-in gyroscope, the acquiring size smart mobile phone being imaged by lamp Id information is uploaded to location server by the distance between lamps and lanterns information, smart mobile phone；

The location server, in map data base return on-site position coordinates, utilize the ginseng acquired in smart mobile phone Number information determine corresponding position in map data base, and are shown on smart mobile phone and real-time update, so as to complete Into positioning.

2. a kind of plant area's alignment system based on visible ray according to claim 1, it is characterized in that, the VISIBLE LIGHT EMISSION Unit includes the master controller based on STM32, LED light source and LED drive circuit.

3. a kind of plant area's alignment system based on visible ray according to claim 2, it is characterized in that, the LED light source choosing By the use of the large power white light LED of 3W as signal source, nominal parameter 9V, 330mA.

4. a kind of plant area's alignment system based on visible ray according to claim 2, it is characterized in that, the LED drivings electricity Input of the transmission information as LED drive circuit that road is generated by the master controller coding based on STM32, by input signal into It gives and biases while row amplification, it is ensured that LED light source works normally, and the LED drive circuit is according to the characteristic of LED light source used By adjusting change of the variable resistance realization to output quantity.

5. a kind of plant area's alignment system based on visible ray according to claim 1, it is characterized in that, in the smart mobile phone Level meter, the gyroscope of setting are used as exploitation hardware, using IOS systems as development environment, system version using Macintosh iMac For more than X EI Capitan, developing instrument is Xcode 7.31.

It is 6. special according to a kind of localization method of plant area's alignment system based on visible ray of claim 1-5 any one of them Sign is to comprise the following steps,

Step（A）, it is seen that the LED lamp id information for needing to transmit is loaded into the light and shade variation of LED lamplight by light emitting unit；

Step（B）, the lamp that LED lamp light and shade changes is received by the use of the camera of smart mobile phone as the terminal for receiving id information Id information that light includes and decoding, parsing obtains the unique identities identification id information that LED lamp is sent, using built in smart mobile phone Level meter obtain the horizontal and vertical tilt information of smart mobile phone, built-in gyroscope is utilized to obtain the ground magnetic biasing of smart mobile phone Angle information, the distance between the acquiring size smart mobile phone and lamps and lanterns that are imaged by lamp information, smart mobile phone upload id information To location server；

Step（C）, the map data base of location server returns to on-site position coordinates, utilizes the parameter acquired in smart mobile phone Information determines corresponding position in map data base, and is shown on smart mobile phone and real-time update, so as to complete Positioning.