CN103150929A - Magnetic field sensor-based vehicle parking state detection system - Google Patents
Magnetic field sensor-based vehicle parking state detection system Download PDFInfo
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Abstract
A magnetic field sensor-based vehicle parking state detection system disclosed by the invention comprises a power supply, a detector and a data processing and transmission module, a power management module of the magnetic field sensor-based vehicle parking state detection system is respectively connected with a processor and a magnetic field sensor, the processor is respectively in two-way data connection with the magnetic field sensor and a PC (personal computer) serial communication tool, and the PC serial communication tool is in two-way wireless connection with an upper computer. The characteristic of the magnetic field sensor that under the affection of external magnetic field interference sources, magnetic field data in each direction greatly change is utilized by the detection system, the detection system judges whether vehicles are parked in an area according to the amplitude of change, and the detection system cannot be easily affected by the interference of temperature change and windy and snowy weathers, has reliable performance, is convenient to install, is cheap, and can be applied in the intelligentized management system of a large parking lot.
Description
Technical field
The present invention relates to a kind of motor vehicle detector, relate in particular to the storing cycle state detection device based on magnetic field sensor.
Background technology
Along with the high speed development of urban transportation, the city vehicle owning amount is more and more, and the parking lot is also more and more increasing, and it is particularly important that the management in parking lot just seems.Particularly whether how large parking lot, in time know the parking stall without car, and show in real time exactly at Control Room, carries out intelligent management, is key in the urgent need to address.The mode of some present detection vehicles, as buried coil, photoelectric tube etc., exist power consumption large, easily damage, the problem such as reliability is low.
Summary of the invention
The invention provides a kind of storing cycle state detection device based on magnetic field sensor, this device has utilized magnetic field sensor under the impact that the external magnetic field interference source is arranged, magnetic field data on all directions occurs more significantly to change, judge according to the amplitude situation that changes whether this zone has storing cycle, do not allow to be subject to temperature variation and the interference of wind and snow weather, dependable performance, easy for installation, price economy, can apply in the intellectualized management system of large parking lot.
Storing cycle state detection device based on magnetic field sensor of the present invention, comprise power supply, detector, data processing and transport module, its power management module connects respectively processor and magnetic field sensor, processor is connected with PC serial communication instrument bi-directional data with magnetic field sensor respectively, and PC serial communication instrument is connected with the host computer double-direction radio.
Described processor adopting LPM0 sleep mode, inner integrated magnetic field detection algorithm, communication data agreement are explained, the record of keys initial value and detection time setting module, the CPU of processor adopting is MSP430G2313.
Described magnetic field sensor adopts HMC5983, and magnetic field sensor is arranged to the SPI communication interface.
For the ease of data transmission and processing, processor and sensor communication adopt the SPI interface.
Further, in order to guarantee can to carry out accurately transceiving data in communication process, processor is communicated by letter with PC serial communication instrument and is adopted the USART interface.
In order to transmit better the data that adapt to on-the-spot sensitivity, accuracy and authenticity, PC serial communication instrument is connected with the host computer double-direction radio that upper computer software has been installed with the serial communication protocol of self-defining mode.
Storing cycle state detection device based on magnetic field sensor of the present invention, following characteristics are arranged: 1, sampling super low-power consumption microprocessor MSP430G2313, when not detecting, allow magnetic field sensor and microprocessor enter the low-power consumption park mode, can realize the operation of low power consumption high efficiency; 2, can according to client's demand, set up the time of detection and the sensitivity of detection on their own; 3, sampling three-axle magnetic field HMC5983 induction detects, and can realize that 3 D stereo detects, and has guaranteed to detect the accuracy of storing cycle; 4, under strong magnetic environment, can work; Eliminate when strong magnetic interference, can realize automatically restoring to original state, not disturbed by external magnetic field; After vehicle is placed a period of time, when car is left this parking stall, the data when can allow magnetic field data return to without car; Externally under strong magnetic interference, situation about being magnetized has occured in magnetic field sensor, can manually realize again recording initial condition data; 5, according to the variation of temperature, set the auto thermal compensation technology, the changes of magnetic field that auto-compensation produces due to temperature difference reason; Can realize round-the-clock, full weather work.
At unattended large parking lot, to realize automatically detecting the situation of parking whether vehicle is arranged on certain parking stall, this equipment is arranged on the centre position on parking stall; When having storing cycle in the above, automatically determine, and to send a signal to host computer be main frame, main frame upgrades the parking situation of parking display screen according to the instruction that receives, and realizes unmanned control, and can accurately guide the driver to be parked in correct position.
Description of drawings
Fig. 1 is the hardware configuration schematic diagram of the storing cycle state detection device based on magnetic field sensor of the present invention;
Fig. 2 is processor internal processes structural drawing;
Fig. 3 is the process flow diagram of operation HMC5983;
Fig. 4 is the process flow diagram that serial ports receives custom protocol;
Fig. 5 is determined with without the car algorithm flow chart.
Embodiment
The power management module of the storing cycle state detection device based on magnetic field sensor of the present invention connects respectively processor and magnetic field sensor, processor is connected with PC serial communication instrument bi-directional data with magnetic field sensor respectively, and PC serial communication instrument is connected with the host computer double-direction radio.As Fig. 1.
Described processor adopting LPM0 sleep mode, inner integrated magnetic field detection algorithm, communication data agreement are explained, the record of keys initial value and detection time setting module, the CPU of processor adopting is MSP430G2313.
Described magnetic field sensor adopts HMC5983, and magnetic field sensor is arranged to the SPI communication interface.
Processor and sensor communication adopt the SPI interface.Processor is communicated by letter with PC serial communication instrument and is adopted the USART interface.PC serial communication instrument is connected with the host computer double-direction radio that upper computer software has been installed with the serial communication protocol of self-defining mode.
Processor adopting low power processor chip MSP430G2313, being under low-power consumption mode, only need the electric current of 1uA, use inner crystal oscillator, communicate by letter with sensor HMC5983 and adopt the SPI interface, before reading HMC5983, this sensor has been carried out the related register configuration, guaranteed the Accuracy and high efficiency that magnetic field data reads, at the inner integrated magnetic field detection algorithm of processor, the communication data agreement is explained, the record of keys initial value, and set detection time.In order to guarantee to move under low-power consumption mode, adopt the LPM0 sleep mode, mainly by serial ports interrupt, external key interrupts or timer interrupts waking up CPU and carries out work, pass through serial communication, according to our agreement can allocating and measuring time, the sensitivity of allocating and measuring need to determine whether minute book terrestrial magnetic field data; Used this chip peripheral and interrupted, timer interrupts, and serial ports receives to send and interrupts, FLASH data read-write operation, simulation SPI operation.Specifically see Fig. 2.
Magnetic field sensor HMC5983 passes through periphery circuit design, this sensor setting is become the SPI communication interface, use ceramic condenser to carry out reset operation to HMC5983, the ceramic condenser equivalent series impedance must be less than 200 milliohms, otherwise will exert an influence to reset circuit.The single power supply mode that HMC5983 adopts, supply voltage 3V adopts four line communication modes, the port that four lines are respectively the corresponding CPU of SPI_CS(is P1.5), SPI_SCK(P2.0), SPI_SDO (P2.2), SPI_SDI (P2.1); The sequence of operation of read-write HMC5983 is:
The operation note (comprising configuration register A, configuration register B, mode register) of configuration HMC5983 reads the continuous reading manner of three-axle magnetic field the data; The mode of configuration register A be adopt average use be 8 mean values as output valve, the output speed of data is: 15Hz, the normal metering system of measurement pattern; The mode of configuration register B is: gain is configured to ± 1.3Ga, and the scope of output is-2048 ∽+2047; Mode register: be configured to the continuous coverage pattern, upgraded data when three axis data in register, the RDY port will be exported high level.Communication interface adopts the SPI communication of standard, that HMC5983 supports standard and pattern fast, frequency of operation is respectively 100KHz and 400KHz, but do not support fast mode, need external pull-up resistor [if the STM32 port arrangement being become " multiplexing recommend output " mode (in the situation that use Hardware I~2C)], if with Simulation with I 2C port will be arranged to " drawing on inside " pattern; In the process of measuring, do not need HMC5883L is carried out reset operation, the operation that can automatically reset in inside, after resetting, can be automatically the magnetic field data that reads under positive pulse be deducted the data that read under negative pulse again divided by 2, send into respective shaft to register in, can offset inner deviation and temperature drift poor; In reading the process of HMC5983, adopt the mode that reads continuously, in the process of whole measurement, be that register upgrades later value for what guarantee to read at every turn, just be provided with a decision content, after reading and writing continuously the XYZ three-axle magnetic field data of a HMC583, the data of a configuration register A are read in the capital automatically, if write the data of 0xFO, continue read-write three-axle magnetic field data, incorrect just the continuation waited for.
The process flow diagram of whole operation HMC5983 is illustrated in fig. 3 shown below, in to the SPI initialization procedure, first having set its frequency of operation is 1MHz, P2.0, the P2.2 of MSP430G2313 processor are set to output port, the direction register of this single-chip microcomputer is set as output type, the direction register of P2.1 is set as input type.P1.5 is as the selecting side of SPI, and also the direction initialization register is output type;
The HMC-5983 configuration, the register A of configuration HMC5983, register B, mode register; Register A is configured to serviceability temperature measurement result is carried out auto-compensation, the numerical value of employing carries out 8 average just output later on, and the output speed of data is 15Hz; Configuration register B is configured to the magnetic field data gain of measuring ± 1.3 Ga, just can automatically remove after each measurement is correct; The configuration mode register adopts four-wire system SPI pattern, and the result of measuring is carried out the test constantly mode;
The test constantly mode in magnetic field is: read-write sequence adopts the SPI read-write sequence of standard, enable the CS end, to SCK signal end clock signal, the address 0xC3 that will read and write continuously at the rising edge of clock signal writes, and next the XYZ magnetic field data of 6 bytes is read, when the reading, high-order front, 16 is one group of data, and three groups of data are deposited respectively, and recycling average value filtering algorithm is got 10 times on average to the result of measuring.Guarantee the correctness of measurement result.
For the work that guarantees that CPU can be stable, adopted the clock of inner 1MHz to carry out work, configured the storage mode of inner FLASH, the working method of timer A0, initialization has been carried out in SPI operation to the HMC5983 operation, and configuration HMC5983 working method, configured the external interrupt mode, be used for an external button and record once local magnetic field data; Accurate for the result that guarantees to measure, the minimum requirement of sensitivity is set to 40.Can carry out work in order to guarantee whole system under low-power consumption mode, it is 20Hz that the timer A0 interruption execution time is set, for the port setting that coordinates this system is determined with time without car, set an intermediate variable register, be in shown in following table 1 when the port level being detected, to change at the setting-up time that interrupts the A0 the inside, timer is according to the time of setting so, and timing wake-up CPU carries out the reading magnetic field sensor and is determined with state without vehicle.
Table 1 is set table detection time
| SEL2 pin level | SEL1 pin level | Set the interval time of detecting vehicle |
| 0 | 0 | 1 second |
| 0 | 1 | 2 seconds |
| 1 | 0 | 5 seconds |
| 1 | 1 | 10 seconds |
Configure HMC5983 and utilized temperature to carry out auto-compensation, read the continuous reading manner of three-axle magnetic field the data; The mode of configuration register A be adopt average use be 8 mean values as output valve, the output speed of data is: 15Hz, the normal metering system of measurement pattern; The mode of configuration register B is: gain is configured to ± 1.3Ga, and the scope of output is-2048 ∽+2047; Allow HMC5983 enter low-power consumption mode in the process of not carrying out data acquisition.
In the present invention, power management module adopts low-power consumption, and with the power regulator module of Enable Pin, stable output 3V allows processor and sensor can guarantee stable operation.
In the present invention, the data of storing cycle situation and sensor need to be passed through the serial communication mode, and data are sent to host computer, and the protocol format of transmission adopts the agreement of the serial communication of self-defining mode.
The baud rate of serial communication is: 19200;
The communication protocol of instruction is as follows:
Instruction data length order number magnetic field sensitivity minute book terrestrial magnetic field standby cumulative and order fulfillment sign detection time
0xB5 0x62 0x0B 0xA1 0x00 0x00 0x0A 0x00 0x00 0x00 0x00 0x00 0xAA
Concrete as:
0xB5 0x62 0x0B 0xA1 0x00 0x28 0x0A 0x00 0x0A 0x00 0x00 0xE8 0xAA
It is all to operate with sexadecimal that serial data sends
Concrete as:
0xB5 0x62 0x0B 0xA1 0x00 0x28 0x0A 0x00 0x0A 0x00 0x00 0xE8 0xAA
Table 2 order format instruction card
Referring to Fig. 4.in order to guarantee to carry out accurately transceiving data in communication process, serial ports receives and operates with interrupt mode, in case there are data to send to processor, processor will wake dormant state up, data are received and judge whether these data meet the demands, determine whether it is that the foundation of protocol data that we define is: all data that begin before the check bit from the data length byte add up, and to 255 remainders, if result of calculation equates with the check sum of transmission, command reception success, to receive to get data, stipulate according to the particular content in agreement, resolve the data message of each byte, the data receiver success sends a string character " OK " to host computer, the success of expression data receiver.In agreement, magnetic field sensitivity has directly determined to judge the changes of magnetic field size of vehicle institute perception, if the data of magnetic field sensitivity are less, perception storing cycle situation is just more obvious, otherwise more not obvious.Instruction Main Function in minute book terrestrial magnetic field is to allow host computer send " 0X0A " instruction, just can automatically record at that time magnetic field data in the inside FLASH of MCU, and preservation; Also allow simultaneously content in next instruction as the time of reading magnetic field data, also can go here and there instruction by this to the running time interval in magnetic field and record (also can pass through outside port SEL1, the port level of SEL2 determines interval time of reading magnetic field data).
Use the Wireless Data Transmission radio station, the data of three-axle magnetic field are sent to the upper computer software of main frame by serial ports, upper computer software is presented at the three-axle magnetic field data on screen in real time, on screen, the energy Real Time Observation is to the situation of change of three-axle magnetic field data, in the situation that without car, the data of three axles are exactly local magnetic field data, but when having car above magnetic field sensor, the data of three axles will have greatly changed.
Have, during without car, the data of magnetic field sensor perception can have obvious variation, and with MATLAB, decision algorithm is analyzed and summed up to three axis data; The formula of algorithm is as follows:
(formula 1-1)
Wherein
, expression has or not the rate of change of magnetic of storing cycle;
when headstock has with a certain distance from magnetic field sensor, the axial output data of each of magnetic field sensor HMC5983 almost do not change, when vehicle slowly when the magnetic field sensor, skew has occured towards the moving direction of car near the magnetic field of vehicle, the installation direction of supposing magnetic field sensor is that X-axis is towards the dead ahead of vehicle mobile, X-axis is sensitive axis of sensor, the magnetic field data output of X-axis will occur than significant change, in vehicle advances process, the vehicle front-wheel is by the top of magnetic field sensor, because wheel is to contain iron-nickel alloy, to cause that larger variation occurs the three-axle magnetic field data, the Y-axis data will be sensitive axis this moment, the Y-axis magnetic field data also just changes, if vehicle continues to move ahead, when near engine the time, X-axis and Z axis are all sensitive axes, the data of this diaxon have larger variation, if when the fast magnetic field sensor of car, larger variation will occur again in X-axis, Z axis output, because the boot of vehicle generally all is equipped with spare tire, certain interference be caused in the magnetic field of X, Z-direction.When vehicle kept away the magnetic field sensor top, each axle output was returned to original state.
Storing cycle is above magnetic field sensor the time, stabilizing magnetic field has on every side occured comparatively significantly to change, disturbance local Distribution of Magnetic Field, this disturbance just can be flutterred with HMC5983 and be grasped this data message, utilizes following formula 1-1 just can accurately judge the situation of parking of vehicle.
The present invention for different automobile types, has gathered mass data by in real process, by analysis, the summation setting value of changes of magnetic field amount is 50, and it is 50 that namely corresponding detection has or not the Sensitirity va1ue of storing cycle, the induction over 50 has car to park, otherwise just parks without car; In order to guarantee to detect the reliability of vehicle, detecting has in the car situation, and larger variation can occur the Z axis data, therefore when being determined with car, if sensitivity surpasses 25, but the data variation amount of Z axis surpasses 10, also be judged to be without car, in other situations, just regard as without car; The removing of XYZ three-axis reference value need to be decided according to the situation of change of summation, if be in 2 minutes in the time, the variable quantity that total variable quantity is no more than 15, XYZ, three axles is no more than 5, can automatically remove one time reference value; Removing like this reference value is in order to prevent long-time placement, the impact that magnetic field data generation drift produces.Concrete be determined with algorithm flow without car referring to Fig. 5.
Claims (7)
1. based on the storing cycle state detection device of magnetic field sensor, comprise power supply, detector, data processing and transport module, it is characterized in that: power management module connects respectively processor and magnetic field sensor, processor is connected with PC serial communication instrument bi-directional data with magnetic field sensor respectively, and PC serial communication instrument is connected with the host computer double-direction radio.
2. according to claim 1 the storing cycle state detection device based on magnetic field sensor, it is characterized in that: processor adopting LPM0 sleep mode, inner integrated magnetic field detection algorithm, communication data agreement are explained, the record of keys initial value and detection time setting module, the CPU of processor adopting is MSP430G2313.
3. according to claim 1 and 2 the storing cycle state detection device based on magnetic field sensor, it is characterized in that: magnetic field sensor adopts HMC5983.
4. according to claim 1 and 2 the storing cycle state detection device based on magnetic field sensor, it is characterized in that: magnetic field sensor is arranged to the SPI communication interface.
5. according to claim 1 the storing cycle state detection device based on magnetic field sensor, it is characterized in that: processor and sensor communication adopt the SPI interface.
6. according to claim 1 the storing cycle state detection device based on magnetic field sensor, it is characterized in that: processor is communicated by letter with PC serial communication instrument and is adopted the USART interface.
7. according to claim 1 the storing cycle state detection device based on magnetic field sensor, it is characterized in that: PC serial communication instrument is connected with the host computer double-direction radio that upper computer software has been installed with the serial communication protocol of self-defining mode.
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103914993A (en) * | 2014-04-24 | 2014-07-09 | 银江股份有限公司 | Intelligent parking detection method based on magnetic field sensor |
| CN104332057A (en) * | 2014-10-24 | 2015-02-04 | 青岛海信网络科技股份有限公司 | Adaptive environment vehicle detection method based on geomagnetism |
| CN104637312A (en) * | 2015-03-11 | 2015-05-20 | 南京颐丰益信息技术有限公司 | Geomagnetic parking space detector and geomagnetic parking space detection method |
| CN105022023A (en) * | 2014-04-22 | 2015-11-04 | 法国大陆汽车公司 | Method for detection of a fixed position of a pre-set distance through activation of a vehicle |
| CN105807699A (en) * | 2016-05-24 | 2016-07-27 | 河南省高迈科技有限公司 | Car-mounted low-power-consumption integrated instrument circuit |
| CN106323257A (en) * | 2016-10-20 | 2017-01-11 | Comlab（北京）通信系统设备有限公司 | Direction angle measuring device and measuring method based on active magnetic field |
| CN106781647A (en) * | 2016-11-30 | 2017-05-31 | 南京理工大学 | The wisdom road patch and its method of work of a kind of Multi-sensor Fusion |
| CN106781671A (en) * | 2017-01-06 | 2017-05-31 | 武汉键停科技有限公司 | It is a kind of to be based on two kinds of parking space state detection methods of sensor cross checking |
| CN106846825A (en) * | 2017-04-06 | 2017-06-13 | 四川辉通云联数据科技有限公司 | Earth magnetism wagon detector, earth magnetism vehicle detecting system and method |
| CN111344536A (en) * | 2017-11-08 | 2020-06-26 | 罗伯特·博世有限公司 | Method for operating a magnetic field sensor and associated magnetic field sensor device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1707283A (en) * | 2004-06-10 | 2005-12-14 | 林贵生 | Underground intelligent vehicle detector |
| JP2006040086A (en) * | 2004-07-29 | 2006-02-09 | Amano Corp | Parking lot managing system |
| CN1885365A (en) * | 2005-06-24 | 2006-12-27 | 龚青 | Vehicle communication apparatus and roadside communication system and connection signal generation method thereof |
| WO2008061540A1 (en) * | 2006-11-20 | 2008-05-29 | Pirelli & C. S.P.A. | Parking management method and system |
-
2013
- 2013-03-05 CN CN2013100685004A patent/CN103150929A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1707283A (en) * | 2004-06-10 | 2005-12-14 | 林贵生 | Underground intelligent vehicle detector |
| JP2006040086A (en) * | 2004-07-29 | 2006-02-09 | Amano Corp | Parking lot managing system |
| CN1885365A (en) * | 2005-06-24 | 2006-12-27 | 龚青 | Vehicle communication apparatus and roadside communication system and connection signal generation method thereof |
| WO2008061540A1 (en) * | 2006-11-20 | 2008-05-29 | Pirelli & C. S.P.A. | Parking management method and system |
Non-Patent Citations (2)
| Title |
|---|
| 吴兴福等: "基于磁阻传感器的无线车辆检测传感器设计", 《北京汽车》 * |
| 赵中琦等: "基于磁阻传感器的无线车辆检测器", 《电子测量技术》 * |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105022023A (en) * | 2014-04-22 | 2015-11-04 | 法国大陆汽车公司 | Method for detection of a fixed position of a pre-set distance through activation of a vehicle |
| CN105022023B (en) * | 2014-04-22 | 2019-07-12 | 法国大陆汽车公司 | The method for detecting the fixation position away from the activation device at vehicle preset distance |
| CN103914993B (en) * | 2014-04-24 | 2016-02-17 | 银江股份有限公司 | A kind of intelligent parking detection method based on magnetic field sensor |
| CN103914993A (en) * | 2014-04-24 | 2014-07-09 | 银江股份有限公司 | Intelligent parking detection method based on magnetic field sensor |
| CN104332057A (en) * | 2014-10-24 | 2015-02-04 | 青岛海信网络科技股份有限公司 | Adaptive environment vehicle detection method based on geomagnetism |
| CN104637312A (en) * | 2015-03-11 | 2015-05-20 | 南京颐丰益信息技术有限公司 | Geomagnetic parking space detector and geomagnetic parking space detection method |
| CN105807699B (en) * | 2016-05-24 | 2018-11-06 | 河南省高迈科技有限公司 | Vehicle-mounted low energy consumption integrative instrument circuit |
| CN105807699A (en) * | 2016-05-24 | 2016-07-27 | 河南省高迈科技有限公司 | Car-mounted low-power-consumption integrated instrument circuit |
| CN106323257A (en) * | 2016-10-20 | 2017-01-11 | Comlab（北京）通信系统设备有限公司 | Direction angle measuring device and measuring method based on active magnetic field |
| CN106781647A (en) * | 2016-11-30 | 2017-05-31 | 南京理工大学 | The wisdom road patch and its method of work of a kind of Multi-sensor Fusion |
| CN106781671A (en) * | 2017-01-06 | 2017-05-31 | 武汉键停科技有限公司 | It is a kind of to be based on two kinds of parking space state detection methods of sensor cross checking |
| CN106846825A (en) * | 2017-04-06 | 2017-06-13 | 四川辉通云联数据科技有限公司 | Earth magnetism wagon detector, earth magnetism vehicle detecting system and method |
| CN111344536A (en) * | 2017-11-08 | 2020-06-26 | 罗伯特·博世有限公司 | Method for operating a magnetic field sensor and associated magnetic field sensor device |
| US11255999B2 (en) | 2017-11-08 | 2022-02-22 | Robert Bosch Gmbh | Method and system for operating a magnetic field sensor using adaptive filter to detect object |
| CN111344536B (en) * | 2017-11-08 | 2022-09-13 | 罗伯特·博世有限公司 | Method for operating a magnetic field sensor and associated magnetic field sensor device |
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Application publication date: 20130612 |